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Escuela de Especialidades “Antonio de Escaño”

INGLÉS TÉCNICO MARÍTIMO

PE-IDM.601(B)



EE “Antonio de Escaño” Departamento de Idiomas INGLÉS TÉCNICO-MARÍTIMO

CONTENTS

CHAPTER 1.- BOILERS

CHAPTER 2.- RECIPROCATING STEAM ENGINE

CHAPTER 3.- INTERNAL COMBUSTION ENGINE

CHAPTER 4.- LINE OF SHAFTING. CRANKSHAFT. PROPELLER

CHAPTER 5.- TURBINES.TYPES

CHAPTER 6.- AUXILIARY MACHINES

CHAPTER 7.- PUMPS

CHAPTER 8.- CONDENSERS & EVAPORATORS

CHAPTER 9.- VALVES

CHAPTER 10.- COMBUSTIBLES & LUBRICANTS

CHAPTER 11.- MEASURES. UNITS. INSTRUMENTS

CHAPTER 12.- METALLURGY´S NOMENCLATURE. METAL´S TOOLS

CHAPTER 13.- ELECTRICITY

CHAPTER 14.- ELECTRIC ENGINES

CHAPTER 15.- DAMAGES. NOMENCLATURE

1 PE-IDM.601(B)






CHAPTER 1

BOILERS

Vocabulary

Air cock. Grifo atmosférico.

Air draught Tiro de aire.

Ashpit Cenicero.

Ashpit door Puerta de cenicero.

Automatic feed water regulator Regulador de alimentación.

Auxiliary boiler Caldera auxiliar.

Auxiliary steam valve Válvula auxiliar de vapor.

Auxiliary feed check valve Válvula de retención auxiliar.

Blow down cock Grifo de extracción de fondo.

Blow down valve Válvula de extracción de fondo.

Blowers Sopladores.

Boiler Caldera.

Boiler feed water Agua de alimentación caldera.

Boiler furnace. Horno de la caldera.

Boiler mountings Accesorios de las calderas.

Boiler shell Envolvente de la calderaBoiler stays Tirantes de la caldera

Boiler stop valve Válvula de comunicación de la caldera

Bridge Altar.

Burners. Quemadores.

Casing. Envolvente.

Combustion chamber. Cámara de combustión.

Cyclone steam separator Separador del vapor ciclón.

Cylindrical boiler Caldera cilíndrica.

Direct flame boiler. Caldera de llama directa.Double ended boiler. Caldera de doble frente.

Dome. Domo.

Downcomer tubes Tubos descendentes.

Drain cock Grifo de purga.

Economiser Economizador.

Feed check valve. Válvula de alimentación.

Feed water. Agua de alimentación.

Fire bars. Parrillas.

Fire tube boiler. Caldera tubular o fumitubular.

Fire bridge. Altar del hogar.

3 PE-IDM.601(B)



EE “Antonio de Escaño” INGLÉS TÉCNICO-MARÍTIMO Departamento de Idiomas

Vocabulary

Forced draught. Tiro forzado.

Fuel burners. Quemadores de combustible.

Furnace. Horno.Furnace door. Puerta del horno.

Gauge glass. Tubo indicador de nivel.

Generator tubes. Tubos generadores.

Grate. Parrilla.

Header. Cabezal.

High pressure boiler. Caldera de alta presión.

Iner casing. Envoltura interior.

Low pressure boiler Caldera de baja presión.

Main boiler. Caldera principal.

Main feed check valve. Válvula de retención principal.

Main steam top valve. Válvula de comunicación.

Manhole door. Puerta de registro.

Natural draught. Tiro natural.

Nest tube. Haz tubular.

Outer casing. Envoltura exterior.

Pressure gauge. Manómetro.

Reheater. Recalentador.Return flame boiler. Caldera de llama de retorno.

Safety valve. Válvula de seguridad.

Saturated furnace. Hogar del vapor recalentado.

Saturated steam. Vapor saturado.

Scotch boiler. Caldera escocesa.

Side water wall tubes. Pared lateral de tubos refrigerados.

Smoke box. Caja de humos.

Smoke tube boiler. Caldera fumitubular.

Soot blowers. Sopladores de hollín.Stay. Estay, virotillo.

Stay tube. Tubo estay.

Steam cock. Grifo de vapor.

Steam pressure gauge Manómetro.

Steam drum. Colector de vapor.

Stop valve. Válvula de comunicación.

Superheat furmace. Horno de vapor recalentado.

Superheat steam. Vapor recalentado.

Superheater. Recalentador.

Superheater tubes. Tubos de recalentado.

PE-IDM.601(B) 4




Three-drum boiler. Caldera de tres colectores.

Up-take. Conducto de humos.

Water drum. Colector de agua.

Water gauge. Indicador de nivel.

Water tube boiler. Caldera acuotubular.Water wall header. Cabezal de la pared de agua.

Water wall tubes. Pared de agua.

Working pressure. Presión de trabajo.

5 PE-IDM.601(B)




BOILER

A boiler is a container that is capable of generating steam by the internal or external

application of heat.

MAIN TYPES OF BOILERS

There are two general classes of boilers: The smoke tube boiler and the water tube

boiler. In the smoke tube boiler, the smoke gases pass through the tubes which are inmersed

in water, and in the water tube boiler, the water passes through the tubes which are

surrounded by gases.

SMOKE TUBE BOILER

The most common type of boiler, among the smoke tube boilers is the “Scotch boiler”.This boiler has a cylindrical steel shell; the ends of this shell are called the front end and back

end. Front end has three or four openings into which the furnaces are fitted. The furnaces are

divided into two parts, the upper part for the fire and gases and the lower part for the ashpit.

The water inside the boiler should be kept to a level above the top of the tubes.

The hot gases pass from the furnace to the combustion chamber in the back of the

boiler, and from there through the tubes to the smoke box and funnel. The water inside the

boiler is converted into steam which is collected at the top of the boiler and from there passes

through a stop valve to the engines. To compensate the loss of water there is a feed checkvalve through which fresh water is pumped into the boiler.

WATER TUBE BOILERS

In this type, flames and hot gases are outside the tubes and the water circulates through

them.

The Yarrow boiler is the classic water tube boiler, it consists in two cylindrical drums

connected by small tubes to and upper drum which collects the steam. The two cylindrical

drums and tubes contain the water, and the steam goes to the engine through a steam stopvalve situated in the upper drum.

The water tube boilers have the advantage over the fire tube boilers in that the steam

may be generated more quickly, and the weight of the boiler and the contained waters is loss,

and also is less danger of explosions.

Nowadays, water tube boilers are provided with superheaters economisers. The

superheat is usually located between the rows of water tubes.

As the superheat steam temperature tends to fluctuate with the rate of steaming of the

boiler and causes loss of engine efficiency, controlled superheat boilers have been developed,as the Babcock Wilcox D-shaped boiler in which the steam drum is mounted vertically over

the single water drum, and is interconected by water tubes.

PE-IDM.601(B) 6




A tranverse baffle, formed by a set of large tubes divides the tubes in a front pass and

rear pass. A single superheater is used and its tubes are set between the fire rows and

generator rows of the front pass. Dampers are fitted at the base of the uptake over each pass,

and the volume of furnace gases can be varied operation of the dampers.

The furnace is formed by a row of “water wall” tubes terminating in a side water

header. An economiser is fitted in the uptake above the dampers.

BOILERS MOUNTINGS

The main fittings in a boiler are:

1. Safety valve to prevent any excess of pressure in the boiler.

2. Feed check valve to admit the water into the boiler in conjunction with an automatic feed

regulator. All boilers are to be provided with two feed check valves connected to separateto separate feed lines.

3. Blow down valve to empty the boiler, blowing the water out to sea. Each boiler is to be

fitted at least with one blow down valve secured direct to the lower part of the boiler.

4. Main steam stop valve to control the passage of steam from the boiler to the engines.

Every boiler is to be fitted with one main stop valve secured direct to the shell.

5. Air cocks to release air when raising steam.

6. Steam pressure gauge to indicate the pressure of the steam inside the boiler. The gauges

are to be placed where they are easily seen.

7. Water gauge to indicate the high of water inside the boiler. Every boilers is fitted with atleast two independent means of indicating the water level in it, one of which is to be a

glass gauge.

7 PE-IDM.601(B)




PE-IDM.601(B) 8




TWIN FURNACE

9 PE-IDM.601(B)






CHAPTER 2

RECIPROCATING STEAM ENGINE

Vocabulary

Air pump Bomba de aireBed plate BancadaBrasses Metal antifricciónCompound engine Máquina compoundCondenser CondensadorConnecting rod Biela

Crankpin Muñón del cigüeñalCrosshead CrucetaCylinder cover Tapa del cilindroCylinder barrel Cuerpo del cilindroCylinder bottom Fondo del cilindroCylinder liner Camisa del cilindroCylinder ring Anillo del cilindroCylinder bore Diámetro interior del cilindroDrain cocks Grifos de purgaEccentric sheave Platillo de excéntrica

Eccentric strap Collar de excéntricaEngine columns Columnas de la máquinaGland Corona o manguito de prensaestopasGovernor ReguladorGuide shoe Patín de crucetaHigh pressure cylinder Cilindro de alta presiónIntermediate pressure cylinder Cilindro de mediaLow pressure cylinder Cilindro de baja presiónPiston ÉmboloPiston rod Vástago

Quadruple expansion Máquina de cuádruple expansiónRelief valve Válvula de seguridadShafting EjesSlide valve chest Caja de distribuciónSlide valve Válvula distribuidoraSluice valve Válvula de correderaStop choke valve Válvula de retenciónStuffing box Caja de prensaestopasTriple expansion engine Máquina de triple expansión

11 PE-IDM.601(B)




ENGINE

An engine is a machine for applying mechanical power, and so, converting energy into

motion. The principal types used for ship propulsion are:

Reciprocating steam engineSteam turbine

Internal combustion engine

RECIPROCATING STEAM ENGINE

The reciprocating steam engine uses the steam in succession through two, three or

more different cylinders, and they may be classified as:

Compound engine

Triple expansion engine

Quadruple expansion engineGas turbine

The steam passes through the boiler stop valve to the engine

THE COMPOUND ENGINE

The compound engine is used for propulsion of small vessels, or in auxiliary engine. It has

two cylinders: the high pressure cylinder and the low pressure cylinder. The steam passes

through the boiler stop valve to the engine stop valve and then successively entering in the

high pressure cylinder and low pressure cylinder, through their slide valves, working on the piston of each cylinder as it expands.

When the steam leaves the low pressure cylinder then passes to the condenser, and is

converted into water by coming into contact with cold pipes and by means of the air pump,

the water pass into a feed tank and from thence into the boiler again.

TRIPLE EXPANSION ENGINE

The triple expansion engine has three cylinder: high pressure, first intermediate

pressure and low pressure cylinder. Steam from the boilers is admitted to the high pressure

cylinder then passes to the intermediate pressure cylinder, and finally to the low pressurecylinder and condenser.

This type of engine is very common in old merchant ships, and the boiler for this

engine has a pressure between 180 to 220 psi square.

QUADRUPLE EXPANSION ENGINE

The quadruple expansion engine has four cylinders: high pressure, first intermediate

pressure, second intermediate pressure and low pressure cylinder.

As the volume of steam increases as the pressure decreases each succesive cylinder islarger in diameter and works at lower pressure than the preceding one.

PE-IDM.601(B) 12




PARTS OF THE ENGINE

The main parts of the engine are:

Cylinders and their connections

ShaftingBedplate

Auxiliary fittings

CYLINDER

The cylinder is the part of the reciprocating engine in which the steam acts to force the

piston from one end to the other and viceversa. It is made of cast iron. The inner surface of the

cylinder is formed by a liner. The piston is attached to the piston rod and this one to the

connecting rod which fits to the crankpin.

The upper part of the cylinder is called cylinder head and is attached to the barrel by

means of stud and nuts.

The lower cover is fitted with a stuffing box and gland to permit the passage of the

piston rod but to prevent the scape of steam.

The steam is distributed into the cylinder by a slide valve, which is contained in a box

or steam chest on one side of the cylinder. This valve is driven from the crankshaft by means

of an eccentric. The top and bottom of each cylinder is provided with a relief valve to prevent

against undue rise of pressure and also a drain cock is fitted at the bottom of the cylinder.

13 PE-IDM.601(B)




PE-IDM.601(B) 14




CHAPTER 3

INTERNAL COMBUSTION ENGINE

Vocabulary

Air compressor Compresor de aire

Air inlet valve Válvula de admisión de aire

Air starting valve Válvula de arranque

Bearings Cojinetes

Bearing loads Cargas en cojinetes

Bearing saddles Soportes de los cojinetes

Bedplate Bancada

Blowers Sopladores, ventiladores

Bridge Puente

Cams Camones

Camshaft Eje de camones

Compression Compresión

Connecting rod Biela

Connecting rod bearing Cojinete cabeza de biela

Coupled AcopladoCooler Refrigerador

Cooling water pipe Colector de agua de refrigeración

Crankcase Cárter del cigüeñal

Crankpin Muñequilla del cigüeñal

Crankshaft Eje del cigüeñal

Crankweb Guitarra

Crosshead Cruceta

Crosshead bearing Cojinete de cruceta

Crosshead shoe PatínCylinder Cilindro

Cylinder block Bloque de cilindro

Cylinder head Culata

Cylinder liner Camisa del cilindro

Exhaust Evacuación

Exhaust manifold Colector de escape

Exhaust pipe Tubo de escape

Exhaust ports Lumbreras de escape

Exhaust valve Válvula de escape

Firing Explosión

15 PE-IDM.601(B)




Flexible coupling Acoplamiento flexible

Flywheel Volante

Four stroke engine Motor de cuatro tiempos

Fuel injection pump Bomba de inyección

Fuel valve Válvula inyectoraGear-box Caja de engranajes

Gland Corona de prensaestopa

Inlet Admisión

Inlet pipe Tubo de admisión

Internal combustion engine Motor de combustión interna

Liner Camisa

Low pressure (L.P.) Baja presión

Lubricating oil pipe Tubería de aceite de lubricación

Outlet Salida

Output Potencia

Piston Émbolo

Piston crown Corona del pistón

Piston rings Aros del pistón

Piston rod Vástago

Reheater Calentador

Relieve valve Válvula de seguridad

Scavenge pump Bomba de barridoScavenging Barrido

Scavenging air cooler Enfriador de barrido

Scavenging air manifold Colector de barrido

Scavenging ports Lumbreras de barrido

Silencer Silenciador

Starting valve Válvula de arranque

Stroke Embolada

Superheat Sobre-calentar

Tie-rods TirantesTrunk-piston Cilindro de tranco

Two-stroke engine Motor de dos tiempos

Valve gear Mecanismo válvula distribuidora

Water jacket Galería de refrigeración de agua

PE-IDM.601(B) 16




INTERNAL COMBUSTION ENGINE

In an internal combustion engine, the power is developed as a result of the combustion

of air and fuel. Types of internal combustion engines are the Diesel or Semi-Diesel, which

are used as main engines in motor ships, and auxiliary engines in steamships. They may beeither of the two-stroke cycle type which gives a power stroke once every revolution, or the

four stroke cycle, which gives a power stroke every two revolutions or the four stroke cycle,

which gives.

In the diesel engine, air is drawn into the cylinder and then compressed by the piston;

when the air is compressed fuel is sprayed into the cylinder at a high pressure, and is ignite by

the hot air and makes it to expand and drive the piston.

The cylinder head has an air inlet valve, a fuel valve and a exhaust valve, and a

starting valve. The cylinders, cylinder heads and piston are all water cooled, to preventcracking due to the high temperature of combustion.

The cycles in a four-stroke type are called:

Suction

Compression

Firing

Exhaust

In the first stroke, when the piston is moving down wards, air goes into the cylinder

through the air inlet valve.

In the second stroke, the air is compressed while the piston is driven upwards and its

temperature reaches 1.200º F.

In the third stroke, the fuel valve is opened and sprays fuel into the cylinder, which is

ignited and when the gas expands it drives the piston downwards.

In the fourth stroke, the piston goes upwards and the burnt gases are driven out

through the exhaust valve.

TWO STROKE ENGINE

The two-stroke engine has much power than the four stroke engine.

In the two-stroke engine, one out-stroke and one-in-stroke representing one complete

revolution of the crankshaft, completes the cycle.

Compression takes place about the beginning of the upward stroke or the piston; at the

end of the stroke fuel is inyected and fired. Expansion takes place on the downward stroke

until the exhaust ports are uncovered, when air under pressure is admitted.

17 PE-IDM.601(B)




A popular type of the two-stroke engine is the “British Polar”. The cylinder head has

only two valves: starting air valve, and fuel valve. Controlled by the piston are the scavenge

air inlet and exhaust valve.

To produce starting air are used compressors. The air is stored in large cylinders atabout 300 psi square.

PE-IDM.601(B) 18




MOTOR “SULZER”

THRUSTSHAFT

CRANKSHAFT

CONNECTING ROD

TURBO-BLOWER

19 PE-IDM.601(B)




Internal Combustion Engines: design details of the Z40 engine

The bedplate is made of steel-plate and features forgedbearing saddles welded on to

the plate. This permits a relatively light, yet stiff and rugged design. By means of tie-rods, the

bedplate and cast cylinder block are placed under compressive stress.

The crankshaft is forged from one block and has exceptionally large dimensioned

crakpins and shaft diameters, this permits the use of normal carben stuel with good impact

values. Furthermore relatively law bearing loads are achieved. This concept assures a high

degree of operational safety even under difficult conditions. The maximun pressure reaches

only about 120 kp/cm2 at full load, so that white metal-bushed bearings, with their known

good operational characteristics can be used special surface treatment of the craknpins is not

required.

The outputs for shafts admitted by the classification societies are considerably above

the nominal outputs. For the crankshafts of a 12-cylinder in-line Z-40 engine, there is for

instance, for Lloyd´s Register a reserve of output of 36 per cent. (pme = 13 kp/cm2, p=127

kp/cm2) (bmep = 185 psi2, p=1806 psi2).

As is customary on two-stroke engines with modest piston speeds, the crankshaft does

not possess counterweights. However in the future, it is planned to fit the Z engines with

counterweights to balance about 50 per cent of the rotating masses. This is undertaken with a

view to the increasing applications where engines are running at full speed under no load or

when they are exposed temporarily to excess speeds, for example on diesel-electric drives ofice-breakers. The characteristics of the bearing load will then also prove more favorable for

normal service as well.

In the layout of the main crankshaft bearings, the upper bearing cap is placed under

compressive stress by means of pressure bolts designed as hydraulic jacks. This design

permits convenient erection since the oil pressure needed for pre-stressing is generated

outside the engine by means of a pump. By this simple means, the correct compression of the

bearing caps and adequate clearance is guaranteed. During operation, the two pressure bolts

are used to feed the bearing with lubricating oil, and the piston with cooling oil, thusobviating the necessity of a separate line to the bearing cap.

The oil fed to the main bearing reaches the crankpin through inclined holes in the web

and thence to the piston through the connecting rod.

For reasons of strength the piston is made from forged steel and carries four

compression rings. The uppermost ring groove is chromiumplated and fitted with a piston ring

having a gas-thight joint.

Cooling of the piston crown is effected by oil, as shown in other types.

PE-IDM.601(B) 20




The fuel injection pumps on the Z-engines are of the helix-controlled type. An

individual pump is provided for each cylinder. The pump casing has two separate chambers

respectively connected to an inlet and an out-let pipe. Priming is carried out from the upper

chamber and the excess fuel not required for injection returns to the lower chamber.

Technical Vocabulary

Bearings loads Cargas en cojinetes

Bearing saddles Soportes del cojinete

Bmep (break mean effective pressure) Presión media efectiva

Counterweights Contrapesos

Chromiumplated Cromado

Clearance Holgura

Compressive stress Carga de compresión

Erection Montaje

Carbon steel Acero corriente, acero carbono

Full load Máxima carga

Groove Muesca, ranura

Gas-thight joint Junta estanca al gas

Hydraulic jack Gato hidráulico

Helix EspiralLayout Disposición

Metal-bushed Recubrimiento de metal

Kp/cm2 Kilopondio por cm2.

Outputs Potencias

Pme (mean pressure) Presión media efectiva

Steel plate Plancha de acero

Stiff Rígido

Stress Esfuerzo

Thight EstancoTie-rods Tirantes

Welded Soldado

21 PE-IDM.601(B)




North-Eastern Reheater Engine

Economy is effected in a reciprocating engine when the steam remains dry through the

expansion from H.P. to L.P. the presence of water assists the conduction of heat away from

the cylinders, and is undesirable for that reason and also from the point of view of economy,in the amount of make-up water required for the boilers due to leakage. When steam remains

dry, very little leakage takes place at the glands. The total make-up required with type of

engine is given as about 1,5 tons per 1.000 h.p.

Efficiency is increased by using steam at the highest possible temperature at the H.P.

end. Not only does the engine gain in efficiency but also, since the heat in the superheated

steam has been taken from the funnel gasses, the efficiency of the whole installation is

increased.

In one installation superheated steam leaves the boliers at 220 psi. square and at 750º

F. Now this temperature is too high to permit an efficient lubrication of the H.P. piston-rings

and liner. The admission temperature of steam to the H.P. is therefore reduced by passing the

high-temperature steam through tubes on the outside of which is the lower-temperature steam

on its way from the H.P. exhaust to the M.P. inlet. In this way the temperature of the steam

being admitted to the H.P. cylinder is reduced to 600º F and the heat given up by that steam is

recovered by the H.P. exhaust steam on its way to the M.P. the admission temperature of the

steam to the M.P. which would normally be 425º F is thus raised to 575º F, at the pressure of

70 psi/sq. in gauge, the saturation temperature is 316º F., so that the steam now has 259º F ofsuperheat.

This is sufficient to keep the steam dry during subsequent expansion. The fitting

employed by which heat leaves the H.P. steam and is picked up by the M.P. steam is called

the reheater or exchanger. Its consists of an outer casing with inlet and outlet branches. A

tube plate on one end carries about one hundred looped tubes, which are expanded in place.

The tube plate is held in place between the flange of the outer casing and the flange of an end

cover, which has a division plate and branches for inlet and outlet of the H.P. steam. Baffles

are fitted within the tubenest to direct the H.P. exhaust so that it passes over the tubes four

times. The reheater is very useful.

Lubricating oil is supplied to points in the cylinder lines and piston-rod glands by

mechanical lubricators which can be adjusted to give the best results as regards wear of the

parts and low oil consumption. Most of this oil is supplied at the H.P. end, because some of

the oil finds its way into the other cylinder being carried there by steam.

Stephenson valve gear is used to operate the H.P. and M.P. poppet valves, there being

four valves per cylinder, two inlet and two exhaust, operated by cams on as oscillating shaft.

The valves are returned to their seats by external springs, and are so designed that they rotatevery slowly, opening and shutting. This helps to keep the valves in good conditions.

PE-IDM.601(B) 22




The recorded fuel-oil comsumption for engines of 4.000 i.h.p. is 0.766-0.799

pd/i.h.p./hour.


Branches Brazos, ramales, tubos

Casing Envolvente

Exhaust Escape, salida

Expanded Mandrilados

Fitting Accesorio

Flange Brida, platina

Gauge Indicado, indicador

Glands Corona de prensaestopas

H.P. (high pressure) Alta presión

Division plate Placa de division

Inlet Admisión

Liner Camisa

L.P. (low pressure) Baja presión

Leakage Pérdida

Make-up Suministrar

M.P. (medium pressure) Presión intermedia

Piston rings Aros del pistónReheater Calentador

Outlet Salida

Steam Vapor

Superheat, to Sobrecalentar

Superheated steam Vapor recalentado

Tube nest Haz tubular

Tube plate Placa de tubos

Valve gear Mecanismo movimiento válvula

distribuidoraCams Camones

Poppet valve Válvula distribuidora

23 PE-IDM.601(B)




P & Diesel Engines

Type 26 MTB-40V is a four-stroke, non reversible, trunk-piston V- engine with

exhaust turbocharging and inter-cooling of the charging air. The cylinder bore is 260 mm. and

the stroke 400 mm. The cylinders are ranged in two banks forming an angle of 45º to eachother, a design that has resulted in a low and compact engine suitable for installation in

engine rooms with relatively little headroom.

The 26 MTB-40V engine is available in units of 10,12, 14, 16 or 18 cylinders,

covering a power range from 1.800 bhp to 3.240 bhp. It is offered in the following three

versions:

26MTBF-40V: Main marine engine for geared or diesel-electric installations

26MTBH-40V: Marine auxiliary engine for generator operation

26MTBS-40V: Stationary engine for driving generators or pumpsIn marine propulsion plants the following three drives are possible:

a) One or more engines coupled through reduction and reversing gears to

fixed pitch propellers

b) One or more engines coupled through reduction gear only and

employing controllable pitch propellers

c) Diesel-electric drive with engines coupled direct to generators

supplying power to an electric motor on the propeller shaft.

The crankcase consists of two parts: a frame and a bedplate bolted togheter. Thecrankcase is provided with ventilation ducts which can be led into the air. On both sides of the

crankcase, large ports give easy access to connecting-rods and main journal bearings. These

ports have light metal covers.

The frame which is made of cast iron, forms the main structural member of the

engine. It carries the main bearings for the crankshaft, the bearings for the two camshafts, and

housing with guides for the actuating gear of valves and fuel pumps. Each cylinder is attached

to the frame with four long studs of special steel.

The bed plate is of cast iron, and serves as reservoir for the lubricating oil. It can be provided with an amply dimensioned oil outlet with strainer to tank, if desired.

The main journal bearing shells are replaceable precision components. They are of

steel lined with leaded bronze and a thin galvanic layer of leaded tin. The main bearing shells

are carried in the frame and have bearing caps of steel designed to allow replacement of the

shells without lowering the crankshaft.

The cylinders are of simple design, each consisting of a separate cylinder cover, a

cylinder liner, and a cooling jacket fixed to the top of the frame with four long studs of special

steel.

PE-IDM.601(B) 24




The cylinder liners are cast in fine-grained high quality perlite-iron. The top flange of

each liner rests on the cooling jacket, while the lower ends are retained by the frame. Rubber

rings are used to seal the joints between the cooling jacket and the liner, and also between the

crankcase and the liner.The cooling jackets are of cast iron. They encase the cylinders and each is provided

with nipples and rubber rings for inlet and outlet of cooling water.The cylinder covers are

made of fine-grained cast iron. They are each fitted with two air-inlet and two exhaust valves,

a centrally located fuel valve, a starting and safety valve, and a valve for measuring gas

pressure in the cylinder cover to prevent contamination of circulating oil. The cylinder covers

are arranged for quick and easy dismantling and refitting with the aid of hydraulic tools.

The crankshaft is a single forging of high quality steel, and the crank pins and

journals are induction-hardened. Each crank pin carries two connecting rods mounted side byside, one from each of pair of cylinders forming the V. The crankshaft is provided with a

coupling flange for connecting to a generator shaft or for flexible coupling between engine

and gear.

The connecting rods are open-hearth steel forgings. The small ends are closed and

provided with bronze liners. The big ends are split at an acute angle to the centre line of the

connecting rod to allow withdrawal of piston and connecting rod through the cylinder liner.

The connecting-rod bearing shells are replaceable precision units of steel and have

leaded bronze linings provided with a thin galvanic layer or leaded tin. The mating surfaces between the rods and the bearing caps are serrated, and the bearing cap is secured with nickel

steel screws.


Dismantling Desmontaje

Fain-grained Textura fina, grano fino

Flange Brida

Floating Parte libre

Frame Bastidor

Fuel pump Bomba de inyección

Gadgoom pin Perno del émbolo

Harden, to Endurecer

Journal Muñón, luchadero

Gear box Caja de engranajes

Ignition point Punto de inflamaciónInjector Inyector

Ports Lumbreras

25 PE-IDM.601(B)




Oil scrapper ring Aro rascador

Scavenging blower Ventilador de barrido

Scavenging pump Bomba de barrido

Scavenge valve Válvula de barrido

Starting motor Motor de arranqueRadial engine Motor en estrella

Trunk piston Pistón de tronco, émbolo buzo

Turbo- blower Turbo soplante

Valve rocker Válvula de balancín

“DETROIT” DIESEL MARINE ENGINE. SERIES 149. TWO-STROKE. V-ENGINE.

SCAVENGING PUMPS

PISTON

CRANKSHAF

CONNECTING

VALVES

EXHAUST

FUEL

VALVE

OIL FILTER

PE-IDM.601(B) 26




CHAPTER 4

LINE OF SHAFTING – CRANKSHAFT-PROPELLER

Vocabulary

Bedplate Bancada

Crankshaft Cigüeñal

Crankwebs Brazos del cigüeñal, guitarras

Crankpins Muñones de biela

Crank-axles Muñones principales

Collar Collarín

Line of shafting Línea de ejes

Liner Camisa

Gunmetal Bronce de cañón

Journals Luchaderos, muñones principales

Main bearings Cojinetes principales

Propeller boss Núcleo de la hélice

Tail-end-shaft Eje de cola

Screw ship Buque de propulsión mecánica

Stern tube Bocina

Thrust bearing Chumacera de empujeThrust block collar Collarín de empuje

Thrust block Chumacera de empuje

Thrust shaft Eje de empuje

LINE OF SHAFTING

A line of shafting in a crew ship consists of: The crankshaft, thrust shaft at one

end, and the other the tail-shaft and between them the intermediate shafts

CRANKSHAFT

The crankshaft is a portion of the shafting composed of cranks rigidly attached to one

another. It converts up-and-down motion of piston into rotary motion of shaft.

Crankshafts may be either forged or built-up. The built-up crankshaft is composed of

a series of crankpins, crank axles, and crank-webs. The crank axles or journals are supported

by the main bearings in the engine bedplate, and the connecting rods work on the crankpins.

27 PE-IDM.601(B)




THE THRUST SHAFT

The thrust shaft rests in the thrust bearings. It is fitted immediately abaft the

crankshaft and consists of a shaft with a number of collars which transmits the thrust of the

propeller to the thrust block shoes and so to the ship. The thrust shaft is supported in bearings.The propeller thrust tends to push the shafting forward but each collar on the thrust shaft rubs

against the face of the thrust shoe and so transmits the thrust to the block and so to the ship.

INTERMEDIATE SHAFTS

The intermediate shafts are fitted between the thrust shaft and the tail-end-shaft.

They have a coupling at each end for bolting to the other shafts by means of the coupling

bolts.

TAIL-END-SHAFT

The tail-end-shaft is the shaft to wich the propeller is fixed. The part of it which is

inside the stern tube is fitted with a liner of gunmetal which can be renewed when worn.

In the after end of the tail-end-shaft enters the propeller boss whiich is secured to the

shaft by a key and a large nut which is screwed tightly on the shaft.

The Crankshaft

The rigid crankshaft is a highcarbon steel drop forging carefully heat-treated to insure

utmost strenght and durability. All main and connecting rod bearing journal surfaces are

electrically hardened by the Tocoo process.

Complete static and dynamic balance of the rotating parts has been achieved by

counterweights forged integral with the crankshaft.

The crankshaft thrust is taken through two-piece bronze washers on each side of therear main bearing. The crankshaft is drilled for full pressure lubrication to the main and

connecting rod bearings.

Two dowels are provided in the crankshaft flange at the rear for locating the flywheel

on the shaft six tapped holes, one unequally spaced, are provided for attaching the flywheel,

owing to this feature, a flywheel can be attached in only one position.

The six-cylinder crankshaft has 7 main bearings, each 31/2” in diameter and 1 1/8”

long.

Since bearing loads take place on the lower half of the main bearing shells and the

upper half of the connecting rod-bearing shells, wear on the shells take place at these points

PE-IDM.601(B) 28




first. If, therefore, main bearing or connecting rod bearing trouble is suspected, the oil pan and

the main bearing caps as well as the connecting rod bearing caps should be removed, one at

time, and the lower half of the main bearing shell and the upper half of the connecting rod

bearing shells inspected for scoring, corrosion, chipping, craking, or signs of overheating. If

crankshaft has been overheated, erxamine the journals for cracks. The backs of the bearingshells should also be inspected for any bright spots. Bright spots on backs of the shells will

indicate that shells have been shifting in their supports and are unfit for further use.

If the crankshaft journals do not show signs of scoring overheating, or abnormal wear,

it will be unnecessary to remove the crankshaft as the condition may be corrected by changing

the worm half of the bearing shells only, providing the opposite half is in unable condition.

Loose main bearings will be evidenced by the wobbling of the flywheel or a drop in

oil pressure.

If the crankshaft journals show signs of overheating or are scored badly, then the

crankshaft must be removed and a new one substituted.

When a crankshaft has been removed for reconditioning for any reason whatsoever, a

through inspection should be carried out before the shaft is again installed in the engine. Such

a check should include:

Blow out all oil passages with air.

Measure all main bearings and connecting rod bearing journals.The journals should be measured at several places on the diameter in order to show the

smallest diameter in case the journals have worn out of round.

Measure the thickness of the main bearing and connecting rod bearing shells.


Bearing cap Tapa del cojineteBearing journal Cojinete del luchadero

Bearing shell Envoltura del cojinete

Connecting rod bearings Chumaceras de biela

Bright spot Punto brillante

Cracking Grietas

Crankshaft Cigüeñal

Check Comprobar

Drilled Barrenado

Dowell Espiga, cabilla, guíaDrop forging Forja a martinete

29 PE-IDM.601(B)




Flange Brida

Flywheel Volante

High-carbon steel Acero de alto carbono

Journal Luchadero

Lower connecting rod bearing Chumacera de biela inferiorMain bearings Chumaceras principales

Oil pan Batea, colector de aceite

Overheated Recalentado

Scoring Rayaduras

Thrust Empuje

Tapped hole Agujero para roscar

Washer Arandelas

Webling Oscilaciones

PE-IDM.601(B) 30




31 PE-IDM.601(B)




THE PROPELLER

Vocabulary

Ahead AvanteBlade Pala

Blade flange Paso de la pala

Boss Núcleo

Built propeller Hélice de palas independientes

Cavitation Cavitación

Controllable pitch propeller Hélice de paso variable

Four bladed propeller Hélice de cuatro palas

Hub Cubo

Key Chaveta

Left-handed propeller Hélice de giro a la izquierda

Pitch Paso

Pitch angle Angulo de paso

Pitch ratio Relación de paso

Propeller Hélice

Propeller slip Resbalamiento de la hélice

Right-handed propeller Hélice de paso a la derecha

Six-bladed propeller Hélice de seis palasSlip Resbalamiento

Solid propeller Hélice sólida

Three-bladed propeller Hélice de tres palas

Tip Punta de la pala

Twin propellers Hélices gemelas

PROPELLER

The propeller is a device which drives the ship through the water. It consists of a boss

or hub carrying three or four radial blades of an approximately helical surface.Propellers are made of cast iron, steel, a non-corrosive alloy of manganese bronze.

A propeller is right-handed when with engines turning ahead, its upper half revolves

from port to starboard, and left handed when the motion is from starboard to port.

The propeller boss forms the central portion of the propeller which carries the blades and

forms the medium of attachment with the tail-end shaft, wich enters into the propeller boss

and is fitted with a rectangular key, and over this key slides a slot of the propeller boss. The

propeller is further secured by a nut which is screwed tightly on the screwed portion of the

shaft.

PE-IDM.601(B) 32




Controllable pitch propeller

In this type of propeller the blades may be turned on their respective vertical axis, as to

neutral position, astern position or ahead position. It is fitted in modern small vessels, usually

in tugs whose engines of internal combustion type turn the propeller shaft continuously in one

direction.

Pitch

Pitch is a term applied to the distance a propeller will advance during a revolution,

supossing there is no slip.

Slip

Slip is the difference between the actual speed of the ship and the speed of the

propeller or engine speed.

Propellers

The most common form of the propeller today is the solid propeller; wich is a single

casting, the blades being cast integral with the bosses, also a very common type is “the built

propeller”.

The built propeller has the blades and boss cast separately, the blades being secured to

the boss with studs and nuts, the heads of which usually faired into the boss with cement.

The chief advantage is that, if one blade becomes damaged beyond repair, it is a

relatively cheap-matter to renew the blade rather than the whole propeller. As a result, we find

that a large number of the twin-screw vessels plying between the British Islands and the East,

having to pass through the Suez Canal, with its attendant risk of damage to the blades, are

fitted with built propellers. A further advantage is that, by elongating the holding-down stud

holes, allowance is usually made for some adjustment to the pitch, should this prove

desirable. The drawback, however, is that the rather large boss necessary to accommodate the

blade flange or palm as it is usually known, leads to certain minor losses in efficiency.

Nevertheless, if the boss is well designed, these losses should not amount to more than 1 or 2 per cent as compared with the equivalent solid propeller.

Controllable-pitch propellers

As it name implies, it is possible to alter, at will, the pitch of this type of propeller to

suit the prevailing resistance conditions. This change is effected by rotating the blade about its

vertical axis, this movement usually being carried out by hydraulic or mechanical means. The

most obvious application is for the double-duty vessel, such as the tug or trawler where the

operating conditions when towing or running free are entirely different. Since it is usually possible to reverse the pitch completely, and so reverse the direction of thrust, it has one

33 PE-IDM.601(B)




obvious advantage when used in conjunction with a uni-directional prime-mover. In this latter

connection, it would seem to have a considerable future when the internal-combustion turbine

becomes a force to be reckoned with in the marine-engineering world.

In multi-engine vessels, where varying numbers of engines have to be operatedefficiently, many large controllable-pitch propellers have been supplied. Many propellers of

this design, for horse-power ratings varying from 500 to over 8.000, are now in operation

throughout the world in ferries, ore-carriers, pilot ships, cargo ships, cross-channel ships,

canal and river traders, trawlers, ice-breakers, whalers, tugs and other ships.

Hydraulically operated propellers

Most widely used of the hydraulically operated propellers is the “KaMeWa”, a

Swedish propeller whose basic design was developed from experience of the Kaplan waterturbine; and, unlike the other principal types, has the operating servomotor positioned

outboard in the hub body.

The servomotor control valve is also in the hub body, and is regulated by a tube down

the hollow propeller shafting. This tube also convoys the operating oil from the oil

distributing box inboard to the control valve.

The forward end of the shaft tube connects with a key which is moved fore and aft by

a sliding ring within the oil distributing box.

An auxiliary servomotor mounted externally to the box is used to move the sliding

sleeve through a fork mechanism. Oil pressure is applied to the system by means of

electrically driven or shaft driven screw or gear pumps.

Advantages claimed for this design are, first, that the ability to change pitch in the

event of the shaft becoming bent is in no way impaired; second, that all the very high forces

involved in the pitch-changing operation are constrained within the boss.

In the unlikely event of electrical or hydraulic failure, a spring or, in the larger

propellers, a series of springs, moves the blades into full ahead pitch.


Blade Pala

Blade flange Base de la pala

Boss Núcleo

Built propellers Hélice de palas independientes.

Canal and river traders Buques de ríos y canalesCast, to Fundir

PE-IDM.601(B) 34




Condition of fouling Condición del casco

Controllable pitch propeller Hélice de paso variable

Cross channel ship Buque, para el servicio del canal

Direction of thrust Dirección de empuje

Doble-duty vessel Buque de doble funciónFerry Transbordador

Fore and aft De proa a popa

Fork mechanism Mecanismo de horquilla

Gear pump Bomba de engranajes

Holding-down stud hole Agujero para alojar los espárragos

Hollow propeller shafting Eje hueco de la hélice

Hub-body Cono del núcleo

Ice-breaker Rompehielos

Key Pasador

Left-handed propeller Hélice de giro a la izquierda

Non-uniform pitch Paso no uniforme o variable

Pitch Paso

Pitch angle Angulo de paso

Pitch ratio Relación de paso

Plying Navegación de línea regular

Propeller Propulsor, hélice

Right-handed propeller Hélice dextrógira o de giro a la derechaScrew propeller Propulsor, hélice

Screw pump Bomba de husillo

Sealing ring Anillo deslizante

Shaft driving Movidos por el eje

Solid propeller Hélice compacta

Studs Espárragos

Tip Punta de la pala

Torque Torsión

Trawlers PesquerosTwin propellers Hélices gemelas

Uniform pitch Paso constante

Wake Estela

Whaler Ballenero

35 PE-IDM.601(B)




PE-IDM.601(B) 36




37 PE-IDM.601(B)






CHAPTER 5

TURBINES. TYPES

Vocabulary

Action turbine Turbina de acción

Ahead turbine Turbina de marcha avante

Astern turbine Turbina de marcha atrás

Axial blow turbine Turbina axial

Axial flow pressure turbine Turbina axial de presión

Barrel Tambor

Blades Palas o álabesBush Corona

Back pressure turbine Turbina de contrapresión

Bollows Fuelles

Cam Leva

Camshaft Eje de levas o camones

Cast, to Fundir

Casing Envoltura

Collar Corona

Cruising turbine Turbina de crucero

Disc turbine Turbina de discos

Drum turbine Turbina de tambor

Dummy Junta laberíntica compensadora

Diaphragm Diafragma

Energy of discharge Energía de flujo

Expanding nozzle Tobera de expansión

Exhaust gas turbine Turbina de escape de gas

Fins AletasFlexible coupling Acoplamiento móvil

Full admision turbine Turbina de admisión total

Full injection turbine Turbina de inyección total

Gas turbine Turbinade gas

Gland housing Envolvente de prensaestopas

Geared turbine Turbina engranada

Grooves Canales, rayaduras

Governer Regulador

Gunmetal Bronce de cañónHeat energy Energía térmica o calorífica

39 PE-IDM.601(B)




High pressure turbine Turbina de alta presión

Hoop Corona

Impulsive turbine Turbina de acción

Jet Chorro

Low pressure turbine Turbina de baja presiónMoving blade of a turbine Paleta móvil de la turbina

Nozzle Tobera

Oil nozzle Tobera de aceite

Parsons turbine Turbina de Parsons

Reaction blades Paletas de reacción

Reaction turbine Turbina de reacción

Radial flow turbine Turbina radial

Rateau type turbine Turbina “Rateau”

Reduction gear Engranaje reductor

Ring of fix blades Corona de paletas directrices

Rotor Rotor

Rubbing Rozamiento

Shaft Eje

Stages Fases

Stationary blade Paleta fija

Steam turbine Turbina de vapor

Stator EstatorSteamnozzle Tobera de vapor

Sluice valve Diafragma

Tangential flow turbine Turbina tangencial

Tandem turbine Turbina tanden

Turbine rotor Rotor de turbina

Turbine wheel Rotor de turbina

Turbine nozzle Tobera de turbina

Turbine casing Envoltura de la turbina

Turbine governor Regulador de la turbinaTurbine diaphragm Diafragma de turbina

Turbine disc Disco de turbina

Turbine disc key Chaveta de disco de turbina

Turbine dummy Émbolo compensador de turbina

Turbine seating Polines de turbina

Turbine shaft Eje de turbina

Turbine shaft bearing Chumacera de eje de turbina

Throttle valve Válvula de cuello, de estrangulación

Torque Fuerza de torsión

Thrust bearing casing Envolvente del cojinete de empuje

PE-IDM.601(B) 40




TURBINE

The turbine is an engine in which a fluid at high pressure pushes against blades

attached radially to a rotor causing it to rotate around its axis. Turbines may be classified by

the fluid driving them as: air turbines, steam turbines, gas turbines.

STEAM TURBINE

A steam turbine is a turbine in a which steam at high pressure flows against a series of

blades set on discs to the main shaft.

In a steam turbine the potential energy of steam is changed into useful work in two

distinct stops. First is converted into energy of motion, called kinetic energy, by the expansion

in a nozzle from which the steam emerges as a jet at high speed; and second this kineticenergy is converted into mechanical energy by directing the steam jet against blades

mounting on revolving rotor or by the reaction of the jet in the expanding passage, if it

revolves.

The turbine consists of a rotor, carrying the blades, the casing in which the rotor

revolves and nozzles or stationary blades through which the steam is expanded or directed.

The advantages of the steam turbines when compared with reciprocating engines, is

that the turbine the turbines require less engine-room, they are lighter in weight, and require

less attendance.

The disadvantages are, that the condensing plant is larger and more expensive, it is

required special heat resistance material, and a reduction gear to allow turbine to run at the

high speed necessary for high efficiency, and the propeller at the comparatively slow for its

best efficiency.

TYPES OF STEAM TURBINES

There are two main types of steam turbines: impulsive turbine and the reaction turbine.

Impulsive turbine. A impulsive turbine consists of a ring of nozzles followed by a row of

blades mounted on a wheel. The steam is expanded in the nozzles and leaves it in the form of

high velocity jets which will be imparted to the rotor blades, and the rotor will rotate at high

speed and so drive the shaft.

The speed of rotation of a single wheel turbine is very high and is used for small

powers, for driving dynamos, etc., but the impulse turbine used on ships have several wheelsfitted with blades and contained in a steam tight casing. The steam passes through a set of

nozzles in a division or diaphragm and the jets of steam are directed on to the blades of the

41 PE-IDM.601(B)




first wheel and cause it to rotate. The spent steam enters the second set of nozzles which are

set in a steam tight diaphragm between the first and second wheels. Again the steam pressure

falls and in its place, velocity is developed in the form of a second jet of jets which strike the

second wheel blades. The steam from this wheel enters a third series of nozzles, drives a third

wheel and so on.

By extracting the velocity in steps or stages the turbine is made to rotate at a more

reasonable speed. All the wheels are made fast at the same shaft, and all run together.

The impulsive turbine is divided in H.P. turbine and L.P. turbine. When the steam has

passed through several wheels in the H.P. turbine is then exhausted to the low pressure

turbine and finally this low pressure turbine exhausts the steam into the condenser.

Reaction turbine. A simple reaction turbine consists of a ring of fixed blades acting as

nozzles and followed by a row of similar blades mounted on the rotor.

One half of the stage pressure drop takes place in the fixed blades, and the steam jets

enter the rotor blades in the same manner as an impulse stage. The rotor blades act as moving

nozzles and expand the steam ever the remaining half of the stage pressure drop. In this type

the steam expands through the fixed and moving blades, resulting in a considerable end thrust.

This type of turbine is called Parson´s turbine. The blades in the first stage or

expansion are relatively short and increase in lenght as the steam increases in volume. The

fixed blades are attached to the inner surface of the turbine casing.

GAS TURBINE

The gas turbines use air which is drawn into a centrifugal or axial compresor and

forced out at a pressure of several atmospheres. The air then enters a combustion chamber

where fuel is injected into the air stream and ignited. The resulting high-temperature gases

drive the turbine.

REDUCTION GEARING

The gearing is the means by which both turbine and propeller may run at their

respective economical speed, the turbine at high speed and the propeller at the comparatively

slow speed for its best efficiency.

Turbines, impulsive and reaction are geared to the propeller by single or double

reduction gear of the double-helical type.

PE-IDM.601(B) 42




43 PE-IDM.601(B)




Turbines

The following information has been supplied by the Superintendent engineer of the “Blue

Funnel Line”.

S.S. “Nestor turbines”

The turbine installation in the Blue Funnel Line S.S. “Nestor” is of the three-casing

impulsive, double reduction gear. Steam is admitted to the high pressure cylinder through

three groups of inserted nozzles containing (in order of opening) seven, three and two nozzles.

The steam admision valves controlling these nozzles groups are housed in the top half

casing, and are actuated from the manoeuvring hand-wheel by means of shafting bevel gears

and Hardy-Spicer flexible couplings.

The total maximum output of the turbines, using twelve nozzles is 8.000 horse power.

With the H.P. turbine running at 6.000 r.p.m. a propeller shaft speed of 125 r.p.m., the

maximum double-reduction gear ratio is 48%.

The glands are of the labyrinth type, having nickle-lead bronze sleeves with machined

internal fins registering with projections turned on the shaft. These sleeves are supported by

springs within the gland housings, and the material is such that should rubbing occur in

serivce, clearance will rapidly be worn without undue local heating. Gland steam is controlled by means of two hand-wheels on the right hand side of the main control panel.

At full power the transfer piping between the H.P. and L.P. cylinders contains steam at

125 p.s.i.g., which results in a force of some 3 tons in the axial direction. In order to reduce

this force which would apply to the H.P. and L.P. casings, the transfer pipe has been pre-

stressed by an ingenious spring mechanism. This reduces the force acting upon it when hot

and under pressure to about half a ton.

When the stern throttle is opened, low pressure, low temperature steam is

automatically admited to two points in the L.P. turbine. Heat produced by windage isdissipated to this steam as it flows to the condenser. The H.P. turbine-blade heights are small,

and the problem does not therefore arise.

No steam whatever is bled from the turbines for feed water heating. Instead a 350 kw

allen back-pressure turbo generator is used continuosly at sea and to a direct-contact feed

heater.

In order to prevent distortion of the rotors due to temperature variations during

manoeuvring periods, a quick-engaging turning gear is provided. As soon as a stop order is

received, a lever mounted centrally on the turbine control desk is moved, and the main

PE-IDM.601(B) 44




turbines be still trailing, a mechanical interlock comes into operation which prevents the

engagement of a clutch.

Once the turbine has come to rest, the interlock permits an electro-pneumatic valve to

pass compressed air to a Westinghouse servomotor. This engages a fine-toothed dog-clutchmounted at the after end of the first reduction pinion of the L.P. turbine. Then contactor relays

close to start the turning gear motor, which rotates the turbine, gearing and shaft assembly at a

very low speed ( six revolutions per hour ). Conversely should an engine is moved to the

appropiate position, when the Westinghouse electro-pneumatic cylinder will operate

instantaneously to throw out the clutch.

The length between bearing centres is 57 in.

The mean diameter of 1st. and 2nd. rows of blades is 22 in.

The mean diameter of 3rd. to 9th. rows of blades is 18 in.The height of the 1st. row of blades is o.6875 in.

The height of the 9th. row is 1.292 in.

The height of the last row of blades in the L.P. is 10 in.


Astern throttle Válvula de estrangulación de marcha atrás

Blade PaletaBled Pret. del verbo “to bleed” = sangrar

Block Corredera de sector

Clearance Intersticio, espacio libre

Clutch Embrague

Contactor relays Relevador, relé automático, contactor

Double reduction gear Engranaje de reducción doble

Engagement Acoplo

Dog clutch Embrague de garras

Feed water heating Recalentador de agua de alimentación

Flexible coupling Acoplamiento flexible

Gland housing Envoltura de los obturadores

Gland steam Vapor de los obturadores

Hand wheel Volante

Housed Alojadas

Glands Obturadores

Fin Aleta, anillo

Fulcrum Punto de apoyoFine toothed Dientes finos

Labyrinth type Tipo laberíntico

45 PE-IDM.601(B)




Lever Palanca

Manoeuvring Maniobra

Main control panel Panel de mando principal

Interlock Bloqueo

Nozzle ToberaPrevent, to Evitar

Quick engaging Acople o embrague rápido

Ratio Proporción

Output Potencia

P.s.i.g. Pounds square inch gage

Pre-stressed Reforzado

Sequence Sucesión, serie

Seal stop Cierre

Shafting bevel gear Engranaje cónico

Sleeve Manguito

Spring leaded De resorte

Rubbing Fricción, rozamiento

Three casing impulse Turbina de acción de tres envolventes

Throw out Desengranar

Top half casing Mitad superior de la envolvente

Transfer piping Tubería de paso

Trail, to ArrastrarTurning gear Virador

Windage Pérdida de energía por efecto del viento

Worn Gastado

PE-IDM.601(B) 46




CHAPTER 6

AUXILIARY MACHINES

Vocabulary

Anchor cable Cadena del ancla

Anchor work Faenas con el ancla

Barrel Tambor o cilindro

Bed plate Bancada

Bearing keep Cojinete del eje principal

Boom Pluma de carga, botalón, botavara

Brakes Frenos

Cable lifter Barbotín

Connecting rod Barra de conexión

Crank disk Plato

Crosshead Cruceta

Cylinders Cilindros

Cylinder drain cocks Grifos de purga de cilindros

Chain locker Caja de cadenas

Chain pipe Bocina

Drumhead Sombrero (del cabrestante)Exhaust pipe Tubo de vapor de exhaustación

Forecastle head Castillo

Gear, to Engranar

Foot brake Pedal del freno de cinta

Hatchway Boca de escotilla

Hawse pipe Escobén

Heaving in Virar

Hoist, to Izar

Main wheel Engranaje principalMooring lines Cabos de amarre

Pinion Piñón

Piston rod Vástago

Reversing lever Sable o palanca de cambio

Screw brake nut Mecanismo de engranaje del barbotín

Shaft Eje

Single purchase Guarnido en sencillo

Small spur wheel Engranaje de eje secundario

Spur wheel Engranaje recto

Steam chest Caja de distribución

47 PE-IDM.601(B)




Steam pipe Tubo de vapor de admisión

Steam pipe flange Brida de la tubería de vapor

Stop valve Válvula de vapor

Spindle Eje

Tie rod Estay de chigreWarping ends Cabirones

Wildcat Barbotín

Winch Chigre, maquinilla

Windlass Molinete

WINCH

A winch is a hoisting or pulling machine which turns a shaft on which is fitted a drum

and two warping ends, and used principally for the purpose of handling, hoisting and lowering

cargo from a wharf or lighter to the hold of a ship. It is also used to take up lines in the

manoeuvres of docking or undocking.

Merchant ships usually have at least two winches at each hatchway.

The driving power is usually steam or electricity, in the case of steam, this is supplied

from the boiler and the supply is controlled by a steam stop valve, and the exhaust steam from

each cylinder returns to the condenser.The steam is admitted to the cylinder and then by means of the piston, piston rod and

connecting rod causes the crank to rotate and so converts the reciprocating motion of the

piston into rotary motion of the engine shaft.

The cylinders are fitted with a drain cock, so that any water formed by condensation of

the steam in the cold cylinder when starting can be removed and thus prevent damage to the

cylinder.

The winch can be geared in single purchase to lift light loads quickly or put into

double purchase to lift heavier load more slowly.

WINDLASS

The windlass is a type of winch designed for heaving in an anchor cable. When not

employed in anchor work the windlass can be used for heaving in mooring lines.

It is installed on the forecastle head so that chains on both bower anchors lead straight,

over their respective wildcats from hawsepipes to chain lockers.

PE-IDM.601(B) 48




The driving power is usually steam or electricity; the steam windlass has two cylinders

which by means of a piston, piston rod, connecting rod and crank, drive the engine shaft; and

the engine shaft by means of a pinion moves the intermediate shaft. On this shaft are fitted the

warping ends.The intermediate shaft has two pinion which move the main wheels on the main shaft

and these wheels, may be connected at will, by means of a clutch to its respective cable lifter

or wildcat, and so it is possible to heave in both anchors when both clutches are engaged, or to

heave in one only, when it is engaged the port or starboard clutch.

CAPSTAN

The capstan is a machine designed for heaving in mooring lines. It consists of a

vertical barrel working on a spindle. The driving power is usually steam or electricity.

In the traditional capstan the top of the barrel has square sockets in which capstan bars

may be placed when working by hand. The lower edge of the barrel carries pawls which

engaged in a rack and prevent capstan reversing or walking back.

The modern capstan has both worn gearing and bevel spur gearing. The worn wheel

shaft drives a bevel pinion which in turn engages with a bevel wheel secured to the underside

of the capstan.

Electric Winches

A large percentage of electric winches are worm driven, whiel others are driven

through epicyclic gearing.

With a worm-geared electric winch the magnetic brake is generally at the commutator

end, and the centrifugal and foot brakes at the end of the shaft beyond the worm casing. The

bearings for the worm wheel shafts are arranged to give the maximum stiffness to the shafts,

with any tendency towards bending reduced to a minimum. This is of importance, as a winch

is subject to sudden shocks. The worm-shaft thrust bearing is now usually of the duplex-type

ball bearing. The earlier designs were fitted with the ordinary thrust disc-type ball bearing,

and due to centrifugal force at the high light-load speed it was found that the bearing balls had

a tendency to exert pressure on their housing, thus wearing them away quickly.

A popular worm-driven winch is the Scott winch. This has a mechanical efficiency of

about 85 per cent and, an electrical efficiency of about 90 per cent. It embodies a series-

wound motor with a speed-limiting shunt winding, magnetic, foot and centrifugal brakes andcontactor control gear, an overload device is also incorporated. The motor is controlled in

49 PE-IDM.601(B)




both directions of rotation by series resistances. The speed is limited to a safe valve by the

shunt winding when the winch is running light and by the centrifugal brake when it is

lowering the load. The lowering speed can be controlled by the magnetic brake, which is

fitted with hand control.

Epicyclic gearing .- With a winch having epicyclic gearing the motor armature is

concentric with the barrel shaft. This type of winch is usually controlled so that the magnetic

and centrifugal brakes are not required, and the winch is fitted with a foot brake only.

The Wilson winch is of a special type, with a motor designed to run at a slow speed of

about 100 r..p.m.. This motor is mounted so as to run free on the barrel shaft and drives this

shaft through epicyclic gearing. It has an electrical efficiency of 75-80 per cent and a

mechanical efficiency of about 97 per cent.

The motor is series wound with a speed–limiting shunt winding, the controller beingof the the contactor type with hand-operated master controller. A foot brake is also fitted.

Windlass

The main purpose of a ship´s windlass is to lift the anchor, and for warping.

The windlass is fitted with a cable-lifter or drum, one for each cable. These lifters are

fitted to run freely on a shaft. They are constructed to fit the links of the cable, and the lifter is

made to fit four or five links round its cicunference, known as four and five snug. Actuallythere are only two links engaged at any one time. On the outer edge of the lifter there is a rim

to take a brake band, and on the end are arranged, side jaws which are made to fit into

corresponding jaws on a gear wheel. This gear wheel is pressed on to the shaft.

In order to clutch or declutch the lifter to or from the gear. A groove is turned in the

boss of the lifter, into which two cods are fitted. These cods are attached to a carrier, which is

moved bacwards and forwards by means of screws geared to a handwheel. A second motion

shaft is fitted with clutch pinions which mess into the gear-wheels on the lifter shaft. This

shaft is also fitted with a warping drum at each end, and when these are in use the cable lifter

shaft is disconnected by declutching the pinions. Geared into this shaft is the first motion

shaft, on which the engine or motor is attached, the first from crank discs and the second to

further gearing.

Electric Windlass.- An electric windlass equipment should incorporate the following

features:

a) The armature of the motor should be designed to keep the momentum as low as

possible.

b) A sliping clutch or its equivalent should be fitted to limit the stress which can beimposed by the applied power, by braking or by the inertia of the moving parts; to

a predeterminated limit based on the proof stress of the cable.

PE-IDM.601(B) 50




c) The maximum possible speed within the limits of the available bhp should be

obtained by increasing the speed at the lighter loads by means of field control.

d) The equipment should give a creeping speed which will house the anchor safely

and allow the motor to stall when the throat of the hawsepipe is reached.

e) The motor must not be disconnected from the circuit on overload. Any excess-

torque device fitted must only reduce the torque to a safe limit.

Capstan

The capstan is generally used for warping (changing a vessel´s position with regard to

a wharf, dock or another vessel tied to a wharf, by means of a common line) and sometimes

for pulling objects in a horizontal direction or handling ground tackle. It is a vertical-

barrelled, rotating device, with pawls at its base to prevent it from reversing, arranged for

either hand or hand and power operation.

Power-driven capstands, steam or electric, consist primarily of the capstan itself, the

reduction unit and the prime mover.

The entire machine can be mounted above deck, or the gear unit and motor or engine

can be situated below deck, connected to the extended capstan shaft. Power-driven units are

usually arranged to operate in either direction,and in some cases where reversing features are

incorporated, the pawls at the capstan base are eliminated. When found on reversing types, the

pawls are equipped with thumb screws to hold them in a raised position so that the barrel

may be rotated in a reverse direction.

51 PE-IDM.601(B)





Armature InducidoBacwards Hacia atrás

Barrel shaft Eje del tamborBearing balls Cojinete de bolasBending FlexiónBoss NúcleoBrake FrenoBrake band Banda del frenoCable lifter BarbotínCapstan shaft Eje del cabrestanteClutch, to EngranarCods Pequeños sectores

Commutator ColectorContactor control gear Engranajes contactoresCrank disc PlatoCreeping speed Marcha muy lentaDeclutch DesengranarEpicyclic gearing Engranaje epicíclicoField control Control de campoForwards Hacia delanteFoot brake Freno de piéGear wheel Rueda dentada

Groove GargantaGround tackle Equipo de fondearLight load Carga en vacío, ligeraLinks EslabonesMaster controller Control principalMesh, to EngranarOverload SobrecargaPawls TrinquetesPrime mover Elemento motorProof Prueba

Reduction unit Elemento reductorRim RebordeRun light, to Girar en vacíoSeries-wound motor Motor de bobinado en serieShunt winding Embobinado en derivaciónSlipping clutch Embrague amortiguadorStall, to PararThumb screws PalomillasWarping Virar cabosWarping drum Cabiron

Wear away, to DesgastarWharf MuelleWorm driven Transmisión por tornillo sin fin

PE-IDM.601(B) 52




CHAPTER 7

PUMPS

Vocabulary

Air pump Bomba de aireBallast pump Bomba de lastradoBilge pump Bomba de sentinaBucket Émbolo de bombaBucket pump Bomba con válvula de émboloCentrifugal pump Bomba centrífugaCirculating pump Bomba de circulación

Chest Caja de bombaDelivery valve Válvula impelenteDouble acting pump Bomba de doble efectoDuplex pump Bomba dobleExhaust port Orificio de escapeFeed pump Bomba de alimentaciónFuel pump Bomba de combustibleLever gear BalancínOutlet SalidaPlunger pump Bomba de émbolo buzo

Ports OrificiosPrime, to CebarPump barrel Cuerpo de la bombaPump box Caja de bombaPump primer CebadorPump rod Vástago de la bombaPump well Pozo de la bombaRadial vanes Paletas radialesReciprocal pump Bomba alternativaRocking lever Balancín

Rotary pump Bomba rotatoriaScavenge pump Bomba de barridoScrew pump Bomba de héliceSelf-priming pump Bomba autocebableSingle-acting pump Bomba de efecto simpleSteam slide valve chest Caja de distribuciónSuction pump Bomba aspiranteSuction valve Válvula aspiranteSingle suction pump Bomba de aspiración simpleVacuum Vacío

Valve gear pump Balancín de la bomba

53 PE-IDM.601(B)




PUMPS

These auxiliaries may be driven by steam, electric motors or internal combustion

engines. They include:

Air pump for extracting the condensed water and vapour from the condenser, and so maintainthe vacuum produced by the condensation of the steam. There are two types of air pumps:

The common air-pump which has three sets of valves, the lower set are foot valves,

next the bucket valves and on top are the head valves.

The Edward´s air-pump, in this pump there is only one set of valves, head valves. The

condensed steam is allowed to flow continuously by gravity from the condenser into the

bottom of the pump. On the down stroke of the bucket the water is projected at a high velocity

through the ports into the working barrel; the rising water is followed by the rising bucket

which closes the ports and discharges the water and air through the valves at the top of the barrel. The lower part of the pump is made conical to suit the bucket.

Circulating pumps are used to circulate sea-water through the tubes of the condenser.

There are two types of circulating pumps: the ordinary simple or double acting reciprocating

pump, and the centrifugal pump.

In the centrifugal pump the mechanical power delivered to the shaft of a centrifugal

Pump by the driving engine is transmitted to the water by means of a series of radial vanes,

the water is admitted into the centre of pump and is gradually put into motion and whirled

round until it arrives at the outlet and to the condenser.

Feed pumps for supplying fresh water to the boilers to maintain water level.

Feed pumps are either worked by the main engine or are independent, such as Weir´s,

Worthington´s, etc.

Lubrication pumps for supplying oil under pressure to the various working parts of the engine

as: bearings, gearing, etc.

Fuel pumps for supplying furnace fuel oil under pressure to the sprayers on the boilers.

Scavenging pumps for introducing scavenging air into cylinders of internal combustion

engines, during exhaust period, displacing burn products and supplying fresh air.

Feed pumps : Worthington high-pressure centrifugal pump

The Worthington high-pressure bvarrel type centrifugal pump is a double casing

pump. The vertical-split inner casing encloses the working parts and is surrounded by an outer

casing barrel.

The cylindrical casing barrel and all pieces welded to it are made of forged steel. The

suction and discharge nozzles are integral with the casing to permit removal of all internal parts without disturbing the piping connections.

PE-IDM.601(B) 54




The chrome steel impellers are of the single-suction enclosed type of special design.

Each impeller and la_ter the entire rotor is dinamically balanced.

The shaft is made of heat-treated alloy steel. To facilitate installation and removal of

the impellers, it is machined with steps of decreasing diameter through successive stages.The shaft sleeves are scured against axial movement by shaft sleeve nuts.

The internal assembly consists of the shaft with impellers, twin volutes with bushings

and stage pieces with wearing rings; it is held together by staybolts.

There are four different shaft sealing arrangements applicable to these pumps: packed

stuffing box, floating ring seal, fixed breakdown seal, and mechanical seal.

The inboard and outboard bearings are steel-back babbitted and horizontally split.

Each bearing support is fitted with adjusting screws and locknuts which permit final location

of the bearings using a dial indicator to check the shaft position.

The base is of welded steel construction with the pump supported at its horizontal

centerline. The pump is doweled to the base at the suction end, so that all expansion due to

temperature rise occurs from this point.

Complete overhauls

A centrifugal pump should not be opened for inspection unless there is definitive

evidence that is capacity has fallen off excessively or unless noise or driver overload indicates

trouble inside the pump. Under normal operating conditions, the length of service beforerenewal of internal parts is required should be 50.000 to 100.000 hours.

The troubles which may occur with pumps and their causes are:

Troubles

Failure to delivery water

Insufficient capacity

Insufficient discharge pressure

Pump requires excesive power

Pump becomes steamboundPump overheats and seizes

Stuffing box leaks excessively

Packing has short life

Pump vibrates or is noisy

Bearings have short life

Floating seal leaks excessively

Fixed breakdown seal leaks excessively

The main causes for these troubles are:

Pump not primed

55 PE-IDM.601(B)




Insufficient margin between suction pressure and vapor pressure

Insufficient speed

Impeller passages partially clogged

Wrong direction of rotation

Fluctuations in heater pressure at the suctionWearing rings, impeller or balancing device worn or damage

Speed to low, or too high

Foreign matter in impeller

Bent shaft

Rotating parts rubbing on stationary parts

Packing improperly installed

Suction valve closed

Misalignment

Bearings worn

Rotor out of balance, resulting in vibration

Excessive thrust caused by a mechanical failure inside the pump or by the failure of

the hydraulic balancing device

Shaft sleeves worn or scored at packing

Incorrect type of packing for pressure and temperature conditions

Gland too tight, resulting in lack of leakage to lubricate packing

Failure to provide cooling water to stuffing boxes

The frequency of a complete overhaul depends upon the hours of work, operation, of the pump, the conditions of service and the care pump receives in operation.

PE-IDM.601(B) 56




57 PE-IDM.601(B)





Axial clearance Huelgos axialesBabbit metal Metal antifricción

Bearing Chumacera, cojineteBent Doblado, encorvadoBush, bushing Casquillo, manguitoClearances HuelgosClog, to Atascar, obstruirClogged AtascadoDowel, to Afirmar, empernarForeign matter Materia extrañaForge steel Acero forjadoFoundation Asiento, basamento

Gland Prensa, prensaestopasHeater pressure Presión del calentadorImpellers ImpulsoresInboard InteriorKeys ChavetasLack Ausencia, faltaLeakage Escape, filtracionesLocknuts ContratuercasMachined AjustadoMisalignment Desalineamiento

Nozzles ToberasOutboard ExteriorOverhauls Revisiones, reparacionesPacking EmpaquetaduraPower Potencia, fuerzaPrime, to CebarRing seal Anillo obturadorSleeve Manguito, casquilloSleeve nut Casquillo de tuercaStaybolts Espárragos, estays

Stage of a pump Grado de aspiraciónSteambound Salto de vaporStuffing box Caja de prensaestopasThrust EmpujeThrust bearing Cojinete de empujeTight Apretado, ajustadoTroubles AveríasTwin volute DifusorVolute Voluta (forma espiral)Wearing rings Anillos desgastables

PE-IDM.601(B) 58




CHAPTER 8

CONDENSERS AND EVAPORATORS

Vocabulary

Air pump Bomba de aire

Aluminium bronze Bronce de aluminio

Brass Latón

Circulating pump Bomba de circulación

Condenser Condensador

Cupre-nickel Cuproníquel

Exhaust steam Vapor de evacuación

Expanded Mandrilados

Cotton-cord packing Empaquetadura de cordones de algodón

Ferrules Férulas

Feed water filter Filtro de agua de alimentación

Feed water heater Calentador para agua de alimentación

Overboard Por encima de la borda

Riveted steel shell Envuelta de chapa de acero remachada

Single flow condenser Condensador de circulación simple

Screwed glands Prensas metálicas roscadasStays Tirantes

Stuffing box Caja de empaquetaduras, prensaestopas

Surface condenser Condensador de superficie

Tube plates Placas de tubos

Two flow condenser Condensador de circulación doble.

CONDENSER

A condenser is vessel in wich is received exhaust steam from a recripocating orturbine engine for purpose of converting such steam to liquid state and so recovering in large

measure.

The two principal types of condensers are:

Contact condenser

Surface condenser

The surface condenser is the type used nowadays, which consists of a riveted-steel

shell through which passes a large number of brass tubes. Sea water is pumped through the

tubes by means of the circulating pump and thence overboard.

59 PE-IDM.601(B)




The steam condenses on the surfaces of the tubes and drops to the bottom of the

condenser and then is extracted by means of the air pump and discharged through a feed water

filter to the feed pump which pumps it to a feed water heater and then by means of another

pump to the boiler.

The circulating water may be made to pass through the tubes, one, two or three times

and so the condensers are of single flow, two flow condenser, etc.

The tubes at the tube plates are fitted with screwed glands or ferrules and sealed with

cotton-cord packing; at the water inlet they are expanded.

EVAPORATOR

The evaporator is an auxiliary machine which converts sea water into fresh water, to

compensate the less in boiler feed-water or for domestic services.

It essentially consists of a chamber in which steam is passed through copper coils of

tubing in order to vaporize admitted sea water. The steam from the sea boiler passes to the

condenser where is converted into the liquid state.

Operation in a surface condenser

Formerly, a condenser was regarded merely as a “box of tubes” and its function as a

convenient means of getting rid of the exhaust steam at low pressure, thus providing somecclean boiler-feed water. It is worth considering for a bit the actual processes going on in the

condenser which will help towards a clearer understanding of the features of modern

condensers.

First, and primary importance, the steam condenses at its saturation temperature and

for its complete condensation it is necessary only for its latent heat to be removed by the

circulating water. If any sensible heat is removed, the condensate temperature falls below that

corresponding to the exhaust steam pressure, and the sensible heat so removed is a loss.

Secondly, not only does the condenser condense the exhaust steam, but it alsomaintains the vacuum in the exhaust system.

The manner of the air removal is of importance, as the presence of air in the condenser

is also responsible for undercooling of the condensate. Just as it is necessary to have a

pressure difference to cause a fluid to flow from one vessel to another, so it is necessary to

have a temperature difference between the steam and the circulating water to cause the heat to

flow from the steam to the water.

In passing through the condenser the circulating temperature rises, and if the steam

temperature is assumed constant, the temperature difference between the steam and water islarge at the water-inlet end and small at the water-outlet end.

PE-IDM.601(B) 60




The heat flow from steam to water is then controlled by the mean temperature

difference between steam and water.

Air quantity and pressure

In a surface condenser it is impossible actually to condense all the steam; there is

always left behind a certain quantity of vapour having the same properties and behaving in the

same manner as the L.P. exhaust steam.

Arrangements of tubes

Condenser are no longer indiscriminately packed with tubes, but the tubes are

carefully arranged witha view to one or more of the following objects:

1º.- To ensure that each particle of steam encounters only the minimum cold surface

required for its complete condensation and to provide for the condensate falling to the

bottom clear of any tubes to avoid undecooling of the condensate.

2º.- To by-pass a certain proportion of the steam round the tubes and allow it to

condense by

direct contact in the “rain” of condensate falling off the tubes, thus heating up the

latter to nearly steam temperature.

3º.- To ensure that all tubes are continuously swept by steam to prevent the air blanket

building up and reducing heat transmission.

4º.- To ensure that steam can penetrate right down to the bottom rows of tubes and so

render effective the greatest possible amount of cooling surface.

Effects of circulating-water velocity through the tubes

Here again there are two conflicting features:

1. The higher the water velocity through the tubes, the faster the heat is carried away,

and hence the greater the heat transmission. The condenser may therefore be made

smaller for any given steam quantity the vacuum may be increased by increasing

the tube velocity.

2. The water-friction loss in the tubes increases as the square of the velocity, hence

the pumping power increases accordingly. Good condenser design and operation

therefore aims at obtaining the highest possible tube velocity commensurate with

reasonable pumping power.

61 PE-IDM.601(B)





By-pass Derivación, paso

Exhaust steam Vapor de escape

Feed-water Agua de alimentaciónLatent heat Calor latente

Packed Aglomerado, relleno

Cooling Enfriamiento

Vacuum Vacío

Water-inlet Admisión de agua

Water-outlet Salida de agua

Rows Filas, hileras

PE-IDM.601(B) 62




63 PE-IDM.601(B)






CHAPTER 9

VALVES

Vocabulary

Admission valve Válvula de admisiónAir starting valve Válvula de aire de arranqueBalance valve Válvula compensadora, equilibradaBalanced slide valve Válvula distribuidora equilibradaBall valve Válvula esférica, de bolaBilge suction valve Válvula de aspiración de sentinas

Blow off valve Válvula de extracciónBody Caja o cuerpo de la válvulaButterfly valve Válvula de mariposaBy-pass valve Válvula de derivación, auxiliarCharging valve Válvula de cargaCheck valve Válvula de retenciónDischarge valve Válvula de descargaExhaust valve Válvula de escapeFeed valve Válvula de alimentaciónGland Prensaestopas

Gate valve Válvula de compuertaFeed check valve Válvula reguladora de alimentaciónHandwheel Volante de la válvulaInjection valve Válvula de inyecciónMain valve Válvula principal, de comunicaciónMain stop valve Válvula de cuelloManoeuvring valve Válvula de maniobra (turbinas)

Non-return valve Válvula de retenciónOutlet valve Válvula de salidaPressure reducing valve Válvula de reducción de presión

Reducing valve Válvula reductoraPoppet-valve Válvula de disco con movimiento verticalRelief valve Válvula de alivio, de descargaSafety valve Válvula de seguridadScavenge valve Válvula de barridoSea valve Válvula de fondo, inyecciónScrew down valve Válvula de asiento ordinariaSlide valve Válvula de distribuciónSeat Asiento de la válvulaSluice valve Válvula de compuerta, corredera

Spherical valve Válvula esférica, de bolaSpring ResorteSpring loaded valve Válvula de resorte

65 PE-IDM.601(B)




Spring loaded safety valve Válvula de seguridad de resorteStarting valve Válvula de arranqueSteam reducing valve Válvula reductora de vaporSteam admission valve Válvula de admisión

Stem VástagoStop valve Válvula de globo, de cierreSuction valve Válvula de aspiraciónThrottle valve Válvula de cuelloValve chest Caja de distribución

VALVES

A valve is a device for controling flow of a fluid in a pipe or conduit.

SLIDE VALVES

The function of the slide valve is to admit steam to the cylinder and cut off supply

when sufficient steam has been admitted, and opening and closing to exhaust. By means of

this valve the steam is admitted first to one side of the piston and then to the other side. This

valve has a straight line reciprocating motion bearing a definite relation with the piston.

SLUICE VALVES OR GATE VALVES

These valves are so named from its gate or disc usually wedge-shaped, which moves perpendicularly to the direction of the flow, giving a straight passage of flow of the diameter

of pipe. These valves are used in pipe lines.

NON-RETURN VALVES OR CHECK VALVES

Are valves permiting flow in one direction only; valve is opened by flow of fluid and

closed by weight of the check mechanism when flow cease, or when the fluid attempts to pass

in the opposite direction.

SAFETY VALVES

Safety valves are automatic relief valves that are set to open at a predetermined

pressure, in the event of excess pressure in boiler, evaporators, air compressors, etc.

The load on a safety valve to balance the pressure may be applied in three ways:

1st. By a simple lever and adjustable weight.

2nd. By a deadweight placed directly over the place.

3rd. By the compression of a spring.

The safety valve should close quickly when the pressure has been reduced to theworking pressure, which the valve is set to blow.

PE-IDM.601(B) 66




STOP VALVES

The stop valves control the supply of steam from boilers to the main engine or engine

room pumps or winches, windlass, etc; in the first case the valve is called main steam stop

valve and in the other case auxiliary steam stop valve.

SCREW DOWN VALVE

A valve which is opened and closed against a seat by means of handdle which rotates

the spindle and the valve which is attached to the lower and of it, by means of a screw thread.

An example of this type is the glove valve.

SEA VALVE

The sea valve is a valve located near the outside plating of a vessel to supply sea waterto the fire pumps, condensers, for flooding the ballast tanks, also for discharging water

overboard from bilge pumps, ballast pumps, etc.

MANOEUVRING VALVE

This is a special valve in a turbine used for increasing and decreasing speed as

required during manoeuvring of the ship.

67 PE-IDM.601(B)




PE-IDM.601(B) 68




CHAPTER 10

COMBUSTIBLES & LUBRICANTS

Vocabulary

Acid number Indice de acidez

Acidity Acidez

Additives Aditivos

Anti-foam Antiespumante

Anti-oxidation additives Aditivos antioxidantes

Anti-rusting additives Aditivos anticorrosivos

Ashes Cenizas

Asphalts Asfaltos

Bloom Fluorescencia

Brown coal tar Alquitrán de lignito

Calorific capacity Potencia calorífica

Cetane number Número de cetano

Characteristics Características

Coke Coque

Crude oil Aceite bruto (sin refinar)

Density DensidadDiesel-oil Diesel-oil

Distillation Destilación

Dropping point Punto de gota

Ductility Ductilidad

Engler Viscosímetro

Fatty oil Aceite graso

Fire point Punto de combustión

Flash point Punto de inflamación

Fuel consumption Consumo de combustibleFuel oil Combustible

Gas-oil Gasoil

Good grade Buena calidad

Gravity Peso específico

Grease Grasa

Grease, to Engrasar

Heavy duty oil Aceite heavy duty, detergente

Ignition point Punto de inflamación

Inhibitor Inhibidor

Kerosene Aceite lampante

69 PE-IDM.601(B)




Kinematic viscosity Viscosidad cinemática

Linseed oil Aceeite de linaza

Lubricate, to Engrasar

Lubricating oil Lubricante

Melt point Punto de fluidezMelting point Punto de fusión

Mineral oil Petróleo

Oil Aceite

Oil sump Colector de aceite

Paraffin Parafina

Penetration Penetración

Petrolatum Petrolato, vaselina

Pour point Punto de congelación

Precipitates Precipitados

Synthetic oils Aceites sintéticos

Shale oil Aceite de esquisto

Self lubricating Lubricación automática

Self-ignition point Punto de autoinflamación

Sludge Lodo

Sump Colector de aceite

Sulphur Azufre

Solubility SolubilidadTars Alquitranes

Thick fat Grasa consistente

Turpentine Trementina

Vaseline Vaselina

Vegetable oil Aceite vegetal

Viscosity Viscosidad

Viscosity index Indice de viscosidad

O.M. (Oil mineral) Aceite mineral

O.M.D. (Oil mineral detergent) Aceite mineral detergenteO.C. (Oil compounded) Aceite compuesto

O.E.P. (Oil extreme pressure) Lubricante para alta presión

O.F. (Oil fatty) Lubricante graso

O.X. (Oil miscellaneous) Aceite diverso

PE-IDM.601(B) 70




SOLID FUELS

Coal is the main solid fuel, and can be classified as:

• Lignite

• Subbituminous coal• Bituminous coal

• Anthracite

Lignite is the coal containing less than 8.300 btu (british termal units) of potential heat.

Subbituminous coal is the coal with a btu content greater than 8.300 and less than 13.000.

Bituminous coal is the coal with a btu content greater than 13.000 and is used in large

quantities for power generation and industrial heating. Bituminous coal is also widely used for

making coke.

Anthracite is the coal with a fixed carbon content greater than 86%. Anthracite ignites less

readily than other coals, but maintain an uniform and content fire.

In addition to its classification by rank coal, is also classified by grade according to the

amount of ash yielded when the coal is burned. High grade coal produces little ash, and low

grade coal produces large quantities of ash.

LIQUID FUELS: CRUDE OIL

Crude oil is destilled by heating it to about 650º F. as it is pumped through coils or

pipe in a furnace. Only a heavy residual oil remains in liquid form as the lighter fractions

vaporize. Both residual oil and vapors go from the furnace into a fractionating tower, which

may be 100 ft. tall, and which contains a series of perforated trays, one above the other. The

hot vapor rises through the perforations, and the residual oil flowa to the bottom of the tower.

As the vapors rise, they become cooler, the various fractions condensing on the trays

at progressively lower temperatures. Lubricating oil condenses first, about halfway up in the

tower. Slightly higher a liquid called gas-oil condenses, and above that kerosene is formed.

Gasoline condenses near the top of the tower, and the remaining vapours are drown off for

further processing.

As crude oil is steadily pumped through the furnace, the fractions flow continuously

from the condensing trays into pipes that go to other parts of the refinery.

71 PE-IDM.601(B)




By further distillation the residual oil is made to yield gas-oil, fuel-oil, asphalt and

coke. The lubricant oil and kerosene are purified with chemicals and made ready for

marketing.

The raw gasoline, after chemical purification is blended with other petroleum productsto make various grades of commercial gasoline. Gas-oil is either purified or converted into

several other products.

TYPES OF LUBRICANTS

Lubricants are classified by origin such as: mineral, vegetable or animal, and by the

state in which exist, such as gas, liquid or solid.

Vegetable oil include: olive, soybean, caster and cotton seed.

Typical solid lubricants are: graphite, molybdenum and tale.

The mineral oil forms the base of the the majority of lubricants and they can be

adapted by addition of various substances to improve its suitability for various used.

Some of the various substances that can be adapted are:

Vegetable oil are added to oils which are required to lubricate moving parts where

water is present.

Detergent additives are used in internal combustion engine oils to hold the carbonformed by combustion of the fuel and lubrication oil in suspension.

Anti-oxidation additives are used in oils when they are exposed to hot gases or hot

engine parts.

Anti-rusting additives and anti-foaming additives are used in turbine oils.

Anti-wear additives are used in hydraulic oils.

Viscosiity improver additives are used in internal combustion oils where it is

necessary to decrease the normal change of temperature.

Soaps are combined under heat and pressure with mineral oils to form greases.

Combustibles & lubricants

50 years of Diesel Engine Lubrication by J.C. Nairm.

Since the inception of the large, low speed diesel engine as a marine prime mover in1913, and especially since 1920, when it emerged as a serious competitor to the to the steam

PE-IDM.601(B) 72




reciprocating engine and the steam turbine, the big diesel engine has presented lubrication

specialists with difficult problems.

In the early days of the marine diesel engine only straight mineral oils were available

for lubrication. The relatively high temperatures of the ring zone and piston undercrowns placed severe demands upon the oxidation stability of oils used for cylinder lubrication, so

that sticking piston rings and skirt deposits were often troublesome, and port blockage

occurred in two-stroke engines. Where crankcase oil was employed for piston cooling,

undesirable carbonaceous deposits formed on piston undercrowns due to over overheating.

A major improvement in lubrication oil refining was introduced from 1929 onwards,

namely solvent refining. Hitherto, lubricating oils had been manufactured by acid treatment of

suitable cuts from a simple fractionating tower, also treatment of residues from suitable crude

oils.

By treating the raw lubricating oil fractions with selected solvents to remove

undesirable constituents, the resultant finished oils have greatly improved viscosity indexes

and oxidation stability, while the tendencies to form sludge and varnish are reduced. There

are, however, some disadvantages of solvent refining. In adition to removing deleterious

unsaturated constituents the process also removes compounds which, to a degree, act as

natural anti-oxidants and lead-carrying agents.

Basic properties desirable in a diesel engine lubricants.

Diesel engine lubricants must always posses good load carrying properties. These are

closely related to the type of oil used and especially its viscosity and viscosity index. A

careful balance must be achieved between an oil with a sufficiently high viscosity at all

temperatures encountered in the working parts of the engine (thus preventing metal-to-metal

contact and wear), and yet not so high as to cause excessive fluid friction and subsequent

power lose.

Ideally, the VI should be so high that there is no change of viscosity with temperature.

Unfortunately, this cannot be achieved in practice, even with the use of special additives

which markedly increase the VI. Paraffinic oils have high natural viscosity indexes also good

oxidation stability, but unfortunately when exposed to high temperatures in the ring zones of

diesel engines they tend to form bands which will produce deposits.

Oil additives

Simple additives, such as fatty oils blended into mineral oils to improve load carrying

have been used for many years. The use of chemical-type additives to improve the natural

properties of mineral oils, or to enhance existing properties is, however, of much more recent

origin. The use of these special additives, which has revolutionized lubricants, commenced inthe mid-1930s.

73 PE-IDM.601(B)




For example, as early as 1935 C.C. Wakefield and Co. Ltd. (now part of Burmah-

Castrol) were granted a patent for “Improvements in relation to the treatment of Lubricant

Oils”. In effect this was to reduce and control oxidation by the incorporation of small amounts

of metallic soaps and other compounds into good mineral oils bases.

Improved oxidation inhibitors or antioxidants are now universally incorporated in

diesel engine lubricants. These have grreatly extended the useful service life of dual-purpose

and crankcase oils, especially of solvent refined oils.

Cylinder lubricants

Special lubricants have been developed after years of research which combine high

alkalinity to neutralize corrosive sulphuric acid, and detergency to minimize deposits

formation: anti-oxidants are also incorporated. Modern diesel cylinder oils now have an initial

alkalinity, expressed as total base number (TBN) of about 65. By using lubricants with good

detergency and load-carrying properties cylinder liner wear is well below normal for much

less severely rated engines.

As long ago as the late 1930s, long before the burning of residual fuels became

common in marine diesel engines, additives were developed which possessed the property of

keeping the piston ring zones and skirts free from carbonaceous deposits.

Such oils, commonly termed detergent or heavy duty (H.D.) oils are new almost

universally used for trunk-piston diesel engines of all types.

Bearing lubrication

As compared with cylinder lubrication, satisfactory lubrication of the bearings and

other running gear of marine diesels is less difficult. With trunk-piston engines, using a dual-

purpose lubricant, a medium viscosity oil possessing suitable detergency alkalinity properties,

gives good performance in the bearings.

In crosshead engines the crankcase oil is used for the lubrication of the running gear

only and, in general, with good bearing design, a high quality oxidation-inhibited oil isadequate.

It is a far cry from the straight mineral oils adequate for engines in the 1920s, to

today´s scientifically formulated and carefully tested alkaline/detergent cylinder oils, also

highly alkaline, for large trunk-piston engines.

Ther is little doubt that conditions will become even more arduous in the future and

that more sophisticated lubricants will be developed to mean engine.

PE-IDM.601(B) 74





Blockage Obstrucción, bloqueo

Carbonaceous Carbonoso

Cooling RefrigeraciónCrankcase oil Aceite de carter

Crude oil Petróleo crudo

Cut-off Grado de admisión

Cuts Rebajas

Fractionary tower Torre de destilación

Fractionate, to Destilar

Inception Principio, comienzo

Lubricating oil Aceite lubricante

Lubrication Lubricación

Non-additive Sin aditivo

Overheating Recalentamiento

Oxidation Oxidación

Paraffinic Parafínico

Port Lumbrera

Raw Crudo, bruto, materia prima

Ring Aro, anillo

Research InvestigaciónRefining Refinación

Sludge Cieno, lodo

Solvent Disolvente

Sticking Pegajoso

Skirt Faldón del émbolo

Steam reciprocating engine Máquina alternativa de vapor


Straight Puro

Trouble AveríaTwo-stroke engine Motor de dos tiempos

Viscosity Viscosidad

Viscosity index Indice de viscosidad

Varnish Barniz

75 PE-IDM.601(B)






CHAPTER 11

MEASURES. UNITS. INSTRUMENTS

Vocabulary

Barometer Barómetro

Brake Horse Power (B.H.P.) Potencia al freno, potencia efectiva

British Thermal Unit (B.T.U.) Unidad inglesa de calor

Bushel Medida de áridos (36,35lts.U.K.,35 lts,

EE.UU.)

Cable Cable (1/10 de milla)

Diagram indicator Indicador de presiones

Dynamometer Dinamómetro

Effective Horse Power (E.H.P.) Potencia neta

Fathom Braza (6 pies)

Foot, feet Pie, pies

Gallon Galón (4,546 lts.U.K.,3,785 lts.EE.UU.)

Gill Medida de 1/8 de litro

Horse-power Caballo de vapor o fuerza

Hundredweight Quintal (EE.UU.100 libras = 45,36 kgs;

U.K. 112 libras = 50,8 kgs.)Hydrometer Hidrómetro

Inch Pulgada (1/12 de pié = 2,54 cm.)

Indicated Horse Power (I.H.P.) Potencia indicada

Long ton Tonelada de 2.240 libras)

Mean effective pressure Presión media efectiva

Mean pressure Presión media

Micrometer Micrómetro

Mile Milla

Nett Horse Power (N.H.P.) Potencia efectiva, potencia útil Nominal Horse Power (N.H.P.) Potencia nominal

Ounce Onza (28,35 grs.) (1,16 libras)

Pint Cuartillo 1/8 galón

Pound Libra

Pound troy Libra de 12 onzas

Pyrometer Pirómetro

Quart Cuarto de galón

Salinometer Salinómetro

Shaft Horse Power (S.H.P.) Potencia axil, potencia al eje

Short tone Tonelada de 2.000 libras

77 PE-IDM.601(B)




Steam gauge Manómetro

Stone Peso de 14 libras

Tachometer Tacómetro

Test-cocks Grifos de prueba

Thermometer TermómetroTorsiometer Torsiómetro

Water gauge Indicador del nivel de agua

BRAKE HORSE POWER (B.H.P.) or NETT HORSE POWER

Power delivered by an engine or motor to the shaft after overcoming all frictional

resistances in the engine. To get the Brake Horse Power it is necessary to fit a brake over the

flywheel.

SHAFT HORSE POWER (S.H.P.)

Net power delivered to the propeller shafting after passing through reduction gears,

thrust block and other transmission devices. The torsiometer gives the Shaft Horse Power.

HORSE POWER (H.P.)

Measure of the amount of work which a mechanical device can do in a unit of time.

INDICATED HORSE POWER (I.H.P.)

Indicated Horse Power is the power developed inside the cylinder, and takes no

account of the work that may be lost in overcoming the functional resistance in the engine.

This horse-power is deduced from an indicator diagram, which record the pressure in relation

to stroke in an engine cylinder at different stages of the work cycle; from it the power

developed in the cylinder can be determined.

NOMINAL HORSE POWER (N.H.P.)

Nominal Horse Power is an obsolete, term with relation with the actual power of an

engine, but it is still used in classification of steamers.

BRITISH THERMAL UNIT (B.T.U.)

The British Thermal Unit is the unit of heat, and is the quantity of heat required to

raise the temperature of one pound of water one degree Fahreinheit.

PE-IDM.601(B) 78




DIAGRAM-INDICATOR

The diagram indicator is an instrument used to obtain a diagram showing the

variations of pressure in a cylinder through the stroke, and so obtaining the indicated horse-

power of the engine and detecting faults in the setting of valves and other faults such as leakyvalves and piston rings.

The principle of operation consists of a flat sheet attached to an extension of the piston

rod, which moves backwards and forwards with it. Connected to the end of the main cylinder

is a small cylinder with a piston, and behind the piston is a spring which opposes the steam

pressure on the small indicator piston, which will move up and down as the steam pressure

varies in the main cylinder. A pencil on the indicator piston-rod marks the sheet which moves

to and fro with a travel equal to the piston travel, and so an indicator diagram is drawn.

PYROMETER

Pyrometers are used when high temperatures have to be registered.

Two types in common use are: the mechanical and the electrical. The electrical has the

advantage over the mechanical, in that it can show temperatures at points some distance from

where the heat exists; for instance the heat in an engine cylinder can be shown on an

instrument a distance away from the engine.

TORSIOMETER

The torsiometer is an instrument which measures the twist over a certain lengt of the

shaft, and is used for determining the shaft horse-power developed by an engine.

SALINOMETER

The salinometer is an instrument to indicate proportion of saline content of water.

A common type of salinometer consists of a bulb and graduated stem which is

weighted at the bottom to make it float upright in the water. The less dense the water the more

it will be immersed and the more dense the higher it will float.

The electric salinometer consists of two electrodes immersed in the water at a

predetermined distance apart and the electrical resistance provides a measure of the degree of

salinity. With the salinometer the condition of the feed water can be determined. A reading of

the salinometer must be taken when taking over the watch and frequently dring the watch.

79 PE-IDM.601(B)




THERMOMETER

The thermometer is an instrument for measuring temperature. The ordinary

thermometer consists of a graduated glass capilary tube with a bulb containing mercury or

alcohol which expands or contracts as the temperature rises or falls. Thermometer are markedwith Fahreinheit or centigrade scales.

Screw-type thermometers are used to register the temperature of steam and fluids in

boilers, tanks, etc. A bulb beyond the thread makes contact with the steam or fluid. They are

usually installed on the boiler, steam chest, etc.

TACHOMETER

A device for measuring speed, especially the speed of a shaft in revolutions per

minute.

WATER GAUGE

The water gauge is an indicator showing the height of water inside a tank or boiler.

Measures: Units

The systems of weights and measures used in Great Britain and in the United States

are in general practically identical, but there are some important differences. For example, the

British use the long ton of 2.240 pds. whereas in the United States the short ton of 2.000 pds.is generally used. The U.S. bushel and the gallon are also different from the corresponding

British units. In the British system the units of dry measure are the same as these of the liquid

measure and include both the gallon and the bushel (equal to 8 gal.).

In the United States, however, the two are not the same, the gallon and its subdivisions

being used for measurement of liquids, and the bushel and its subdivisions being used to

measure dry goods.

The U.S. gallon of 231 cu. in. is divided into 4 liquid quarts, or 128 fl.oz. The U.S.

bushel of 2.150,42 cu.in. is divided into 32 dry quarts.

The British Imperial Gallon is larger than the U.S. gallon, being equal to about 6/5

of U.S. gallon, and is divided into 4 qts. or fl.oz.

The British Imperial Bushel is about 3% larger than the U.S. bushel and is divided

into 32 qts.

Another difference between the two systems of weights and measures is the use of the

“stone” as a British unit of weight equal to 14 pds.

In Canada the British Imperial units are used, except that the short ton of 2.000 pds. is

used instead of the long ton of 2.240 pds., and the stone is not used.

PE-IDM.601(B) 80




81 PE-IDM.601(B)






CHAPTER 12

METALLURGYVocabulary

Air furnace Horno de reverbero, de tiro natural.

Air quenching Temple al aire, auto-temple

Alloy Aleación

Alloy steel Acero aleado

Annealing Recocido

Anodizing Anodizado

Arc furnace Horno de arce

Arc welding Soldadura con arco

Ash Ceniza

Babbit metal Metal antifricción

Bearing bronze Bronce para cojinetes

Bearing metal Metal para cojinetes

Billet Palanquilla

Black plate Chapa sin recubrimiento

Blacksmith welding Soldadura en frío

Blast furnace Horno alto

Bloom Desbaste laminadoBoiling point Punto de ebullición

Brass Latón

Brazing Soldadura fuerte, latonado

Breaking load Carga de rotura

Breaking stress Esfuerzo de rotura

Brittle Frágil

Brittleness Fragilidad

Bronze Bronce

Browned steel Acero pavonadoBushing metal Metal para cojinete

Butt welding Soldadura a tope

Carbide Carburo

Carbon steel Acero al carbono

Carbonizing Cementación

Cast Colar, fundir

Cast iron Hierro colado, hierro fundido

Casting Pieza obtenida por fundición

Cementation Cementación

Charcoal Carbón vegetal

83 PE-IDM.601(B)




Chilled cast iron Hierro colado enfriado rápidamente

Chromate steel Acero cromado

Chrome Cromo

Chrome steel Acero al cromo

Chromium CromoChromizing Cromado

Clay Arcilla

Coal Carbón

Coating Revestimiento

Coke Cock

Converter Convertidor

Crack Grieta

Creep Fluencia

Dead steel Acero calmado

Dead annealing Recocido a fondo

Dead-soft steel Acero extradulce

Die Molde, matriz

Dip brazing Soldadura por inmersión

Draw plate Hilera

Drawing back Revenir

Drop forging Forja con matrices

Elastic breakdown FatigaElongation Alargamiento

Embrittlement Fragilización

Embrittlement crack Grieta de fragilidad

Endurance Límite de resistencia

Etching Ataque

Fatigue limit Límite de fatiga

Fissure Fisura

Flame cutting Corte con soplete

Flask Caja de moldeoFlaw Grieta

Flux Fundente

Forge Forja

Forging Forjado en caliente, pieza de forja, trabajo

de forja

Foundry Fundición

Fracture Fractura

Furnace Horno

Galvanizing Galvanizado

Gray cast-iron Hierro colado, fundición gris

PE-IDM.601(B) 84




Grinding Amolado

Gun metal Bronce de cañón

Hammer forging Forja con martillo

Hardening Endurecimiento

Hardness DurezaHeat, to Calentar

Heat treatment Tratamiento térmico

High-carbon steel Acero alto en carbono

High duty Buena calidad

High-speed steel Acero de corte rápido

High steel Acero alto en carbono

Ingot Lingote

Internal stress Tensión interna

Iron Hierro

Iron ore Mineral de hierro

Journal brass Bronce para cojinetes

Ladle Cuchara para metal fundido

Lead Plomo

Light alloy Aleación ligera

Limestone Caliza

Loop Tocho

Low alloy steel Acero de baja aleaciónLow steel Acero de poco carbono

Maleable Maleable

Medium steel Acero de proporción media en carbono

Melt Fundir

Melting point Punto de fusión

Metallurgia Metalurgia

Mild steel Acero dulce

Millind Fresado

Mold MoldeMolding box Caja de moldeo

Molten metal Metal fundido

Nickel steel Acero al níquel

Notch effect Efecto de entalladura

Open hearth furnace Horno Martin Siemens, horno de solera

Open hearth steel Acero obtenido mediante el horno Martin-

Siemens

Open steel Acero efervescente

Ore Mineral

Pattern Modelo

85 PE-IDM.601(B)




Peat Carbón de turba

Pig iron Arrabio

Pit Picadura

Plain carbon steel Acero corriente en carbono

Plate PlanchaPot furnace Horno de crisol

Press Prensa

Pricking Punzonado

Quenching Temple

Reagent Reactivo

Rolling Laminación

Run steel Fundición maleable

Rust Herrumbre

Sand Arena

Sand mold Molde de arena

Scrap Chatarra

Seam Grieta superficial

Seam welding Soldadura de costura

Semisteel Semiacero

Shearing strenght Resistencia a la cizalla

Shrinkage Contracción

Silica SíliceSilicon steel Acero al silicio

Slab Desbaste plano de laminación

Soft quenching Temple suave

Soft solder Soldadura blanda

Soft steel Acero suave

Soldering Soldadura blanda

Spar Espato fluor

Spot-welding Soldadura por puntos

Stainless steel Acero inoxidableSteel Acero

Steel casting Acero moldeado

Stove Estufa

Strain Deformación por exceso de carga

Strength Resistencia a la rotura

Stress Tensión, esfuerzo

Sulphide Sulfuro

Sulphur Azufre

Tempering Revenido

Tensile strength Resistencia a la tracción

PE-IDM.601(B) 86




Testing Ensayo

Tin Estaño

Tin plate Hojalata

Tool steel Acero para herramientas

Torch SopleteToughness Tenacidad

Water hardening Temple en agua

Water quenching Temple en agua

Wearing test Ensayo de desgaste

Weld Soldar

Welding Soldadura

Welding flux Fundente para soldar

Welding rod Varilla para soldar

White cast iron Fundición blanca

Wire drawing Trefilado de alambre

Wrought iron Hierro bajo en carbono

Wrought steel Acero forjado

Metals used in machinery

The material used for the manufacture of a component is dependent upon the

mechanical stress and the heat stress to which it is subjected.The components of heat engines and machinery for transmitting power are subjected

to high mechanical stress and may also require to resist considerable heat stress. Such

components are therefore usually made from steel which has high tensile strength and good

heat resistant properties. Steel is allowed with various metals to increase one, or both, of these

properties.

The non-ferrous metals: copper, brasses, bronzes, etc, are generally associated with

components which are lightly stressed but are in contact with sea water, for they are corrosion

resistant. Various alloys of comparatively high tensile strength have been produced, however,and these can often be used instead of alloy steels, which are expensive and present some

manufacturing difficulties.

Although aluminium in its pure state is not often used, aluminium alloys are being

increasingly used in machinery systems. When alloyed with nickel, copper, magnesium and

silicon, a very good weight/strength ratio can be obtained. Most aluminium alloys are corrosin

resistant, provided that in use their coupling with copper-based alloys is avoided.

Rotary and reciprocating components are subjected to high stresses and are usually

made of carbon steel or alloy steel.

Examples: Steam turbines: rotor shafts, rotor forgings, gearing.

87 PE-IDM.601(B)




Steam reciprocating engines: pistons, piston rods, connecting rods,

crankshafts, valve operating gear.

Diesel engines: connecting rods, crankshafts, valve and valve operating gear,

gearwheels.

Gas turbines: compressor shafts, compressor discs, turbine shafts, gearing.

When moving parts are also subjected to high temperaturre and erosive effects they

are made of stainless iron (for moderate stresses) or stainless chromium steel (for higher

stresses).

Examples: Steam turbine blading and pump impellers. For resistance against

severe corrosive effects, the austenitic stainless steels 18/8 chromium nickel

alloys are used.

Non-moving parts, when subjected to high tensile and bending stress, are also madefrom steel.

Examples: All forms of high pressure piping for steam, and furnace fuel-oil,

and the flanges Boilers drums, boiler tubes.

When exposed to high temperature and erosive effects of superheated steam they are

made from stainless chromium steel.

Examples: Superheated steam valves and valve spindles. Monel metal, a nickel

copper alloy may be used in this range.

When subjected to high gas temperatures, above 850º F, a creep-resisting molybdenumsteel alloy is employed. ”Creep” is the permanent growth of a metal after subjection to

extreme heat.

Examples: Gas turbine nozzles and guide blades.

When resistance to furnace and burning temperatures is required without the

protection of brickwork, a heat-resisting steel alloy is used which contains silicon and

tungsten.

Examples: Gas turbine combustion tubes and fittings.

Boiler superheater tube supports.

Castings subjected to high pressure or high temperature are made of cast steel.

Examples: H.P. turbine casings, high pressure valve boxes.

Cast iron

Although this metal has high compressive strength, the tensile strength is very low,and

themetal is liable to fracture under shock. It is not therefore in general use for machinery. But

it is easily cast into intrincate shapes, and affords a good lubricating surface when machined.When cast under special conditions to produce a close grain, including sometimes a trace of

PE-IDM.601(B) 88




alloy metal, it is used for lightly stressed components which are well supported to avoid

fracture.

Examples: Piston rings, slide valves, cylinder heads of small internal combustion

engines, cylinder blocks of small internal combustion engines.

Non-ferrous metals and alloys

These metals: copper, brass, bronze, etc., have high resistance to sea water corrosion,

but generally have low tensile strength. They are used extensively in the manufacture of

lightly stressed components in contact with sea water.

Copper: Very ductile, very high relative conductivity.

Cupro.nickel: A copper nickel alloy which has high resistance to erosion. Examples:

Condenser tubes, cooler tubes.

Brass: A copper and zinc alloy, easily cast and machined. Examples: H.T. brass,

propellers.

Bronze: A copper and tin alloy which when further alloyed with other metals to

produce gunmetal, aluminium bronze, phospher bronze, nickel bronze, etc., has

a comparatively high tensile strength while retaining the non-corrosive

property. Examples: Bearings bushes, shaft sleeves. All forms of castings in

contact with sea-water.

Aluminium

This is one of the lightest metals known and has high relative conductivity. It is not

generally used in pure state, but is alloyed with silicon for common use.

Examples: Lightly stressed castings for all forms of ancillaries. When alloyed with

copper, nickel, magnesium, and silicon to produce “Y” alloy, the tensile strength and

resistance to corrosion is much improved, and the high relative conductivity is retained. This

alloy is therefore used very extensively where reduction in weight combined with rapid

dispersal of heat is required.

Whitemetal

This is a tin, copper, zinc and antimony alloy of very good anti-friction properties and

is used very widely for bearings. It has a low melting point and must be continuously supplied

with lubrication to prevent the collapse of the material. Engine are usually in the form of a

shell of steel or bronze which is "whitemetalled" internally.

89 PE-IDM.601(B)





Alloy Aleación

Alloy steel Acero aleado

Aluminium AluminioAluminium alloy Aleación de aluminio

Ancillaries Dependientes, secundarios

Austenitic stainless steel Acero inoxidable austenítico

Bearing bushes Revestimiento de cojinetes

Bending stress Esfuerzo de flexión, dobladura

Boiler drum Colector de caldera

Boiler tube Tubo de caldera

Brass Latón

Brickwork Enladrillado

Bronze Bronce

Carbon steel Acero al carbono

Cast Colar, pieza obtenida por fundición

Casting Colada, pieza de fundición

Cast iron Hierro colado, hierro fundido, fundición

de Hierro, arrabio

Cast steel Acero fundido, acero colado, acero

moldeadoChromium nickel Níquel cromado, cromoníquel

Chromium Cromo

Collapse Debilitar

Compressor Compresor

Compressor shaft Eje del compresor

Conductivity Conductividad

Connecting rods Bielas

Copper Cobre

Corrosion CorrosiónCrankshaft Cigüeñal

Creep Fluencia

Creep resistance Resistencia a la fluencia

Cupro nickel Cuproníquel

Cylinder block Bloque del cilindro

Cylinder head Culata del cilindro

Ductile Dúctil

Flange Brida

Forgings Pieza forjada

Gearwheel Rueda dentada

PE-IDM.601(B) 90




Gearing Engranaje

Growth Aumento

Guide blades Paletas directrices

Gunmetal Bronce de cañón

Heat treatment (H.T.) Tratamiento térmicoHeat engines Máquinas térmicas

Heat stress Resistencia al calor

Magnesium Magnesio

Mechanical stress Resistencia al calor

Molibdenum Molibdeno

Monel metal Metal monel

Nickel Níquel

Nickel bronze Cuproníquel

Non-ferrous metals Metales no ferrosos

Non-metallic materials Materiales no metálicos

Phospher bronze Bronce fosforoso

Piping Tubería

Piston Embolo

Piston rod Vástago

Pump impellers Impulsores de la bomba

Rotor forging Rotor

Rotor shaft Eje del rotorSilicon Silicio

Stainless steel Acero inoxidable

Steel Acero

Steel alloys Aleaciones de acero


Steam reciprocating engine Máquina alternativa de vapor

Shaft sleeves Manguitos del eje

Stress Esfuerzo

Strength ResistenciaSuperheated steam Vapor recalentado

Superheated steam valves Válvulas de vapor recalentado

Tin alloy Aleación de estaño

Tungsten Tungsteno

Valve operating gear Válvula accionada por engranaje

Valve spindles Ejes de válvula

Weight strength Resistencia al peso

Whitemetal Metal blanco

91 PE-IDM.601(B)




MACHINE TOOLS

Vocabulary

Automatic lathe Torno automáticoBack center Contrapunta

Bad plate Banco de fundición

Band saw Sierra continua

Bays Naves (talleres)

Benches Bancos de trabajo

Blades Álabes, paletas

Blast machine Máquina sopladora

Boring Taladrado, agujereado

Boring-bar Barra porta-barrena

Boring cutter Cuchilla de taladro

Broach, to Escariar, mandrilar

Broaching machine Mandriladora, escariadora

Buffin machine Bruñidora mecánica

Calking machine Retacadora

Casing Envolvente

Circular saw Sierra circular

Clamp MordazaClamp dog Brida de arrastre

Center bit Broca de centrar

Centre rest Luneta

Cone pulleys Polea escalonada

Countershink, to Avellanar

Countershink bit Avellanador, broca de avellanar

Corrugated iron Hierro ondulado

Cutter Cuchilla

Cutting tool CuchillaChange gear Cambio de velocidades por engranaje

Chasing Fileteado

Chuck Plato

Chuck later Torno al aire

Dead centre Contrapunta, punta del cabezal móvil

Direct current Corriente continua

Distribution board Cuadro de derivación

Drilling machine Taladradora

Drill-press Taladradora

Drills Brocas

PE-IDM.601(B) 92




Drill chuck Portabrocas

Engine lathe Torno paralelo o de puntas

Erecting shop Taller de montaje

Expansion reamer Escariador ajustable

Face lathe Torno al aireFace plate Plato portapiezas, plato

Fitting Accesorio

Follower rest Luneta móvil

Footstock Contrapunta

Foreman´s office Oficina del Capataz

Forging Forja

Frame Bastidor

Gear wheel Rueda dentada

Grinder Rectificador

Grinding machine Máquina de esmerilar

Grinding wheel Muela

Grindstone Muela

Hand trimmer Recortadora de mano

Head stock Cabezal

Helical gear Engranaje helicoidal

High speed cutter Cuchilla de gran velocidad

Horizontal milling machine Fresadora horizontalIndependent chuck Plato de mordazas independientes

Inserted blade cutter Fresa con cuchillas insertadas

Jaw Mordaza

Jaw lathe chuck Mordaza de plato de torno

Jib crane Grúa de pescante

Knurling tool Herramienta moleteadora

Lathe Torno

Lathe bed Bancada

Lathe centre Punta de tornoLathe chuck Plato de cabezal

Lathe dog Perno, mordaza

Lathe head Cabezal de torno

Lead saw Sierra de cinta

Machine shop Taller mecánico

Mill, to Fresar

Milling cutter Fresa

Milling machine Fresadora

Milling tool Fresa

Millstone Muela

93 PE-IDM.601(B)




Morse taper Ahusado Morse

Mortise Muesca

Mortising machine Mortajadora o escopleadora

Mortising Mortajado, escopleado

Natural draught Tiro naturalPattern shop Taller de modelado

Pattern maker Modelista

Pillar drilling machine Taladradora de columna

Pipe bending machine Máquina curva tubos

Plane, to Cepillar

Planer Cepilladora

Planning machine Cepilladora

Press Prensa

Profile cutter Fresa perfiladora

Punchin machine Punzonadora

Radial drilling machine Taladradora radial

Ram Corredera

Reciprocal saw Sierra alternativa

Ream, to Escariar

Repetition lathe Torno de repeteción

Riveting machine Remachadora

Rolling LaminadoSand papering machine Lijadora

Sawing Aserrado

Sawing machine Sierra mecánica

Screw cutting machine Torno de filetear

Shaper Limadora

Shape, to Perfilar

Shavings Virutas

Side cutter Fresa de disco

Side milling cutter Fresa de corte lateralSlide Guía

Smithy Herrería

Spindle Husillo

Spindlehead Portahusillo

Steady Luneta

Straight reamer Escariador cilíndrico

Straight turning Cilindrado

Stranded Trefilado

Surfacing Acabado

Tail stock Contrapunta

PE-IDM.601(B) 94




Tapered Cónico

Tapper reamer Escariador Cónico

Tapping Roscado

Tapping machine Máquina de taladrar tubería

Thread, to FiletearThreaded Fileteado

Tool box Carro porta-herramientas

Tool carriage Carro porta-herramientas

Torsion meter Indicador de torsión

Travelling crane Grúa corrediza

Turning Torneado

Turret lathe Torno revólver

Tuyeres Toberas

Universal chuck Plato universal

Works Fábrica

MACHINE TOOLS

Machine tools are mechanical apparatus for doing work with a tool. The main machine

tools are:

• Engine lathe

• Drill press

• Milling machine• Grinder

• Shaper

ENGINE LATHE

The lathe is a machine tool used for shaping cylindrical surface by the action of

stationary cutting tools which are pressed against the work while it is rotating

The esential parts of a lathe are:

• Bed plate Bancada

• Headstock Cabezal

• Tail stock Contrapunta

• Tool carriage Carro porta herramientas

The headstock houses a rotary shaft and its driving mechanism attached to the

headstock is the chuck which holds the work.

The tailstock may be moved to any position on the bed and clamped in it, it is used to

support the work.

95 PE-IDM.601(B)




DRILL PRESS

The drill press is a machine-tool for drilling holes in metal with a rotating drill. It

consists of a work table on which the work is clamped and a power rotated vertical spindle

above the table which carries the drill tool.

The drill press most known is the pillar drilling machine, its essential parts are:

• Frame Bastidor

• Column Columna

• Table Mesa

• Base Base

• Table arm and gear Brazo de la base y mando de movimiento

• Spindle sleeve Husillo portabrocas

• Hand feed wheel Mando de movimiento avante• Motor Motor

MILLING MACHINE

This tool is not found in the machine shop of merchant vessels. It is used for working

metal with a rotary toothed-cutter, as a moving table carries the work against the cutter. The

work is rigidly supported in the table.

GRINDING MACHINE

The grinding machine in the ship´s machine shop is usually of the double type, having

two grinding wheels and the driving motor between them.

SHAPER

A machine-tool for making straight cuts with a sharpened tool held on a reciprocating

ram. The work is supported on an adjustable table. On the head of the ram is the tool holder.

PE-IDM.601(B) 96




97 PE-IDM.601(B)




PE-IDM.601(B) 98




HAND TOOLS

Vocabulary

Adjustable wrench Llave universalAnvil Yunque

Ball hammer Martillo de bola

Beam clamp Mordaza de bao

Bearing scraper Rasqueta para ajuste

Bench vise Tornillo de banco portátil

Box wrench Llave de vaso, llave de tubo

Bolt clippers Cortador de pernos

Breast drill Berbiquí de pecho

Caliper Calibre o pié de rey

Cape chisel Buril

Cant file Lima triangular

Center punch Granete

Cold chisel Cincel o cortafrío

Combination square Escuadra universal

Copper face hammer Mazo de cobre

Crow bar Pié de cabra

Chain pipe wrench Llave para tubos de cadenaDefletometer Flexímetro

Die set Juego de matrices, cojinetes, terrajas

Die stock Potacojinetes o porta terraja

Divider Compás de puntas

Double end scapper Rasqueta de doble cabeza

Double end wrench Llave fija de dos bocas

Drive pin punch Botador

File handle Mango de lima

Flat file Lima planaFlat nose pliers Alicates de punta plana

Hack saw blade Hoja de sierra para metales

Hack saw frame Armazón de sierra

Half round file Lima de media caña

Hand reamer Escariador de mano

Hand tap Macho de terraja a mano

Hand vise Tornillo de apretar a mano

Hatchet Hacha pequeña

Hickory mallet Mazo de madera

Inside calipers Compás de gruesos interiores

99 PE-IDM.601(B)




Lead hammer Mazo de plomo

Linoleum knife Cuchilla para cortar empaquetadura

Mallet Mazo

Micrometer caliper Palmer o micrómetro para exteriores

Monkey wrench Llave inglesa Nippers Tenazas

Outside calipers Compás de gruesos exteriores

Pipe wrench Llave para tubos

Point box wrench Llave de estrella

Portable electric drill Taladradora eléctrica portable

Ratchet Catraca o chicharra

Round file Lima redonda

Round nose plier Alicate de punta redonda

Round punch Sacabocados

Shave hook Rasqueta para ajuste

Scaling hammer Piqueta para óxido

Scissors Tijeras

Srewdriver Destornillador

Screw tap Macho de terraja

Single end wrench Llave fija de una cabeza

Sledge hammer Mandarria

Snips Tijeras para cortar planchaSocket wrench Llave de tuerca de boca tubular, de cubo

Soldering iron Soldador

Speed indicator Contador de revoluciones

Square file Lima cuadrada

Steel tap Cinta métrica de acero

Steel rule Regla de acero

Steel square Escuadra ordinaria de acero

Surface gage Gramil de trazador

Tap Macho de terrajaTap wrench Bandeador o volteador

Thickness gages Juego de tientas o galgas

Vise Tornillo de banco

Wire gage Galga para medir espesores de alambre

Wire scratch brush Cepillo de alambre

Wrench Llave de tuercas

PE-IDM.601(B) 100




101 PE-IDM.601(B)




PE-IDM.601(B) 102




Parsons Marine Turbine Works at Wallsend

(Extract from a report published in 1905)

The Marine Works at Wallsend-on-Tyne were organised in 1897, thirteen years afterthe first turbine was manufactured for driving electric generators.

The practical demonstration of the marine turbine was with the construction in 1894 of

the first turbine steamer, the “Turbinia”. The success attained encouraged the formation of

the new company, “The Parsons Marine Steam Turbine Company Limited”. This company

established the marine works at Wallsend-on-Tyne, at which were designed and manufactured

all marine turbines made up to the year 1904. This establishment called “The Turbinia

Works” was situated four miles from Newcastle, on the bank of the River Tyne, embraced an

area of 23 acres and a river frontage of 900 ft., with a wharf for the mooring of vessels duringthe period of fitting machinery on board.

The workshops include machine shops, blading shops, test house, pattern shop, copper

smithy, brass foundry, smithy, extensive stores and an experimental deparment.

Electric power is of course, used throughout the works, and it was only fitting that the

current should be taken from the adjacent “Carville Power Station” where the Parson Turbo

Generator is extensively applied and efficiently run. There is in the works a large steam

producing plant, including one cylindrical and two water tube boilers for use in testing the

turbines before leaving the works.

The tools in the pattern shop include two planing machines, circular, universal and

band saws, spindle machine, mortice, and drilling machine, four lathes, a comprehensive

wood-working machine, sand-papering machine and hand trimmers. Benches with special

vices have been arranged for about one hundred-pattern makers. Adjoining there is a store

about 100 ft.long and 40 ft.wide, built entirely of corrugated iron as a prevention against fire.

The brass foundry is served by a 10-ton travelling crane. There are twelve fires, with a

tall chimney to give a good natural draught.

The copper shop has nine brazing forges, supplied with blast from a shot´s blower.

Compressed air pipes are laid throughout the shop in connection with portable, pneumatic,

calking and riveting machines. The other appliances include a pneumatic hammer, a shearing

and punching machine, an hydraulic pipe-bending machine, circular saws, and a drilling

machine.. A 5-ton travelling crane serves the part of the shop where the heavier items are

worked, and in addition, jib cranes swing over all the fires.

In the smithy forgings up to 3 tons are produced with the use of special furnaces and a

large power-driven pneumatic hammer. There are also a number of smith´s hearts with watercooled tuyeres for finishing small works.

103 PE-IDM.601(B)




The bays of the machine and erecting shop have the following main tools: a large

boring machine, wich will take casings up to 16 ft. in diameter and 50 ft. in length. There is

also a large lathe for turning rotors. The planing of large cylinders casings is done on a heavy

vertical and horizontal planner.

There is a 90-in. centre duplex sliding surfacing, and a screw-cutting lathe to take a

job 55 ft. 6 in. between centres, and to swing 15 ft. over the bed and sliding carriage. This

lathe is driven by a variable speed direct current motor. There are four-speed cone pulleys. A

face plate chuck 12 ft. diameter with external gearings provided with four loose steel jaws on

the front.

Next to this lathe is a horizontal boring machine, designed especially for boring out

and grooving turbine casings. Beyond this boring machine is a new vertical and horizontal

planing machine, a double horizontal drilling, boring, tapping, milling and studding machine.

There are also in this bay two shafting lathes and machine for calibrating torsion motors, for

measuring shaft horse-power.

In the centre bay are also the tool shop and tool store. In the tool shop are benches and

vices, as well as a screw-cutting lathe, a milling machine, several grinding machines, a large

twist drill grinder to finish drills up to 4 in. in diameter, and several small drilling machines.

Above the tool store is the foreman´s office.

The southern end of the three bays is devoted to the erecting of rotors and casings; the

blading of them, and the water and steam testing of the completed turbines.There are two works devoted entirely to the work of forming the blades to the correct

size, the blades are cut by a patent blade press and the holes in the roots of the blades are

drilled in small special drilling machines.

A special test house is used for steaming and testing the smaller sized turbines. A 30-

ton travelling crane runs the whole length of the shop. At one end of this building are the three

phase and direct-current distribution boards, and a 100-kilowatt Vickers mootor generator.

The work at Wallsend has been associated chiefly with the experimental testing and

calculation of blading, blade strength, and blade capacities in marine turbines. There is also

apparatus greatest effect in a given size of cooler. Thus the efficiency of machinery wheter by

land or marine purposes can be tested in the experimental department of the Heaten from the

generation of the steam to its conversion to work in any form.

This record, demonstrates the possession by the firm of a complete knowledge of the

problems to be solved and there is justification for the hope that still better results with the

turbines will reached in the future.

PE-IDM.601(B) 104




CHAPTER 13

ELECTRICITY

Vocabulary

Accumulator Acumulador

Alternating current Corriente alterna

Alternator Alternador

Ammeter Amperímetro

Ampere Amperio

Amplitude Amplitud

Anode Ánodo

Arc Arco

Armature Inducido (imán), armadura (dinamo)

Battery Batería

Braided cable Cable trenzado

Cathode Cátodo

Cell Pila

Circuit Circuito

Circuit breaker Disyuntor, interruptor

Collector Colector, toma de corrienteConductor Conductor

Connection Conexión

Cut-out Disyuntor

Dielectric Dieléctrico

Dry cell Pila seca

Earth line Línea de tierra

Electric bell Timbre eléctrico

Electric circuit Circuito eléctrico

Electrolyte ElectrolíticoElectromagnet Electroimán

Electromotive force Fuerza electromotriz

Electroscope Electroscopio

Filament Filamento

Flexible cord Cordón flexible

Fuse Fusible

Galvanometer Galvanómetro

Generator Generador

High frequency current Corriente de alta frecuencia

Induced current Corriente inducida

105 PE-IDM.601(B)




Inductor Inductor, rotor

In series En serie

Insulator Aislador, aislante

Ion Ion

Joint EmpalmeLamp Lámpara

Lead Alambre aislado de conexión

Live Con corriente, activo

Magnetic field Campo magnético

Mains Red de suministro, de distribución

Moving iron ammeter Amperímetro de núcleo giratorio

Moving coil ammeter Amperímetro de bobina giratoria

Negative electrode Electrodo negativo

Negative pole Polo negativo

Parallel series connection Acoplamiento en series paralelas

Phase Fase

Plug Enchufe

Polarization Polarización

Pole Polo

Positive electrode Electrodo positivo

Positive pole Polo positivo

Primary cell Pila primariaResistance Resistencia

Rheostat Reostato

Series wound Arrollado en serie

Self induction Auto-inducción

Secondary Secundario

Single phase-generator Alternador monofásico

Shunt Derivación

Shunt circuit Circuito derivado

Socket CasquilloSolenoid Solenoide

Spark Chispa

Switch Interruptor

Switch board Cuadro de distribución

Terminals Bornes

Three-phase generator Alternador trifásico

Two-phase generator Alternador bifásico

Voltage Voltaje, tensión

Voltemeter Voltímetro

Wavelength Longitud de onda

PE-IDM.601(B) 106




Winding Devanado, bobinado

Wire Alambre

Yoke Culata

Electricity and production of a current

Electricity is a form of energy; that is, capable of doing work. Scientists have evolved

a modern theory called the “electron theory” which explains the nature of electricity, but it

will be sufficient for our purpose if we understood how an electric current is produced and

what it can do. Electric current is produced in two ways, viz; by chemical action in a cell or

battery, or by magnetic means in a dynamo or generator.

There are three general effects caused by electric current. These are: magnetic, heatingand chemical effects. If a wire carrying a current of electricity is brought near a small

compass needle, the needle will be deflected from the magnetic meridian, i.e., it will cease to

point to the magnetic pole. The deflection will depend upon the direction of the current

flowing in the wire and on the position of the wire relative to the needle. This is one example

of the magnetic effect or influence of a current.

After some time has clapsed it will be also discovered that the wire has become heated

by the passage of the current throught it. Thus the phisical properties of the wire have been

changed when a current flows in it, although we cannot actually see the current itself.

The chemical effect is observed when an electric current is passed through certain

solutions or compound liquids. These liquids are found to descompose into their separate

constituents under the influence of the current.

The four principal units which are used to compare electric currents define their

pressure, strength, the resistance set up against theeir flow by the material through which the

currents are passing, and power developed. These units are called: the volt, ampere, ohm and

watt respectively.

The volt is the electrical unit of pressure or electromotive force and is the pressure

necessary to cause a current of one ampere to flow along a wire whese resitance is one ohm.

The ampere is the electrical unit of current strength and is defined by the chemical

effect of a current on a solution of nitrate of silverin water, deposits silver at the rate of

0,001118 grammes per second.

The ohm is the electrical unit of resistance to current flow, and is defined as the

resistance set-up by a column of mercury 106,3 cms long and one square millimetre in cross

sectional area, when at the temperature of melting ice.

107 PE-IDM.601(B)




The watt is the electrical unit of power and is the power developed by a current of one

ampere at a pressure of one volt..

Magnetic fields

Ampere discovered in 1820 that two parallel current-carrying conductors were

attracted toward each other if the currents were flowing in the same direction, and repelled if

the currents flowed in the opposite direction. Eleven years later, Faraday discovered that a

changing current in one conductor would induce a voltage in a parallel conductor and cause a

current to flow if the parallel conductor formed a closed loop. We know that electrical

currents consist of moving charges and that the actions described above are the results of

charges moving or being accelerated in the wires. The phenomenon of forces between

accelerated charges will be considered under the heading of induced voltage.

Some of the force phenomena between moving charges can be handled quantitatively

by formulas that give the force between currents or current elements directly, but in general it

will be much more effective to consider that one group of moving charges produces a

magnetic field, which reacts upon another group of moving charges or another current. In

general, no other solution is available when the conductors carrying the currents are

surrounded, or in the near vicinity of iron or other so-called “magnetic-material.”

Let us now consider the development of the concepts of magnetism, through which the

force action between the two wires may be explained. The current in a conductor isconsidered to set up an action of some nature in a closed path around the conductor. This

action is called a “magnetomotive force.” The magnetomotive force, in turn, produces another

quantity called “field intensity,” which exists at all points around the wire and sets up another

quantity called “flux density” at the corresponding points. Both flux density and field density

are vector quantities, i.e., they have both magnitude and direction. The term “flux density”

suggests the term “flux,” since density implies the ratio of some quantity to length, area, or

volume. Flux, or more definitely, magnetic flux, is defined as the integral of the flux density

taken over the area through wich the flux passes. The space in which the magnetic quantities,

magnetomotive force, field intensity, flux density, and flux, are said to exist is called a“magnetic field”.

All off the above magnetic quantities are useful in calculating force between moving

or accelerating charges in various situations. However, the quantity flux density is the only

one needed in connection with the force between two parallel wires. One of the current-

carrying wires is considered to produce a flux density in the surrounding space, and the other

current-carrying wire is said to experience a side thrust because of its location in this magnetic

field.

A beginning concept of magnetism may be obtained from the above discussion, but before any of the quantities can be used analytically, it will be necessary to define the

quantities and their corresponding units rigorously with the aid of defining equations.

PE-IDM.601(B) 108




CHAPTER 14

ELECTRIC ENGINES

Vocabulary

Air gap EntrehierroAlternating current generator Dínamo de corriente alternaAlternating current motor Motor de corriente alternaAlternator AlternadorArmature InducidoArmature winding Devanado de inducidoBearing CojineteBipolar BipolarBipolar dynamo Dínamo bipolarBrush EscobillaBrush holder Porta escobillaCarbon brushes Escobillas de carbónCoil BobinaCommutator ColectorCompound dynamo Dínamo de excitación compuestaCompound winding Bobinado doble, mixtoCore Núcleo

Direct current generator Dínamo de corriente continuaDirect current motor Motor de corriente continuaDouble magnet Imán dobleDrum armature Inducido de tamborElectromagnet ElectroimánElectrostatic generator Generador electrostáticoExternal circuit Circuito externoFields coils Bobinas de campoFields magnets InductorFour pole dynamo Dínamo tetrapolar

High frequency alternator Alternador de alta frecuenciaInductor InductorInduction motor Motor de inducciónIn parallel Acoplamiento en paraleloIn series Acoplamiento en serieIron core Núcleo de hierroLoops of wire EspirasMagneto Máquina magnetoeléctrica, magnetoMagnets core Núcleo del imánPermanent magnet alternator Alternador de imán permanente

Poles PolosPolyphasic PolifásicoRheostat Reostato

109 PE-IDM.601(B)




Ring armature Inducido de anilloRotating armature Inducido giratorioRotor RotorSelf excited dynamo Dínamo de autoexcitación

Separately excited dynamo Dínamo de excitación independienteSeries dynamo Dínamo con excitación en serieSeries wound Devanado en serieShunt DerivaciónShunt dynamo Dínamo con excitación shuntSynchronous motor Motor sincrónicoSingle phase MonofásicaSingle magnet De un imánSleeve ManguitoSlip rings Anillos de frotamiento

Soft iron discs Discos de hierro dulceSpindle HusilloStator Estator, inducido de un alternadorStarting rheostat Reostato de arranqueTurbo-alternator Turbo alternadorTurbo-dynamo Turbo dínamoTransformer TransformadorWinding DevanadoWire gauze brushed Escobilla de tela metálicaYoke Culata

PE-IDM.601(B) 110




111 PE-IDM.601(B)




PE-IDM.601(B) 112




Physical aspects of electromechanical energy conversion

Any electromechanical energy-conversion mechanism is a coupling device between

the eletrical and the mechanical systems utilizing the medium of a magnetic or an electric

field. The field must react on the electrical system to produce a voltage and hence a currentand on the mechanical system to produce a force or torque and hence linear or rotary motion.

Generators and motors utilize the magnetic field as an intermediary and take advantage of

Faraday´s law of induction, viz., that an induced voltage which is proportional to the time rate

of change of flux linkages appears in a winding. Intimately associated with this effect, and

related to it through the conservation-of-energy principle, is the production of a force on a

current-carrying conductor in a magnetic field; the latter effect may alternatively be regarded

as a force proportional to the angular rate of change of flux linkages with a winding. The two

effects are present in both generators and motors, a statement wich simply emphasizes the

inherent reversibility of energy-conversion processes. The main distinction between

generators and motors, therefore, is the direction of energy flow. The energy irreversibly

converted to heat plays no basic role in the conversion process, although the presence of

losses must be accounted for in the final formulation of performance theories.

Among the essential parts of almost every type of generator and motor are two sets of

windings wound on, or embedded in slots in, iron cores. The primary function of one set, the

field winding, is the establishment of a magnetic field in the machine. The other set, the

armature winding, is the one in which the emf of counter emf of rotation is induced; currents

in it are intimately related to the torque or counter torque produced. Thus, the words fields andarmature are functional descriptions of the windings; the words stator and rotor describe only

their location. Structural considerations (and the necessity for commutation in d-c machines)

determine the winding locations in individual machine types.

Three principal types of machines accordingly appear: synchronous machines, with

direct current in one winding, the field winding, and alternating current available from or

impressed at the terminals of the other winding; d-c machines, with direct current not only in

the field winding but also available from or impressed on the terminals of the other winding;

and induction machines (together with a-c commutator machines such as the a-c seriesmotor), with alternating currents in both windings. All three types are capable of generator

and motor action, but the last is rarely used commercially for genetor action. Certain

conditions must be satisfied for successful energy conversion, one of which is that magnetic

fields produced by the two sets of windings must have the same number of poles. The action

of specific machines can be examined from the Blv, Bli viewpoints or from the viewpoint of

the component magnetic fields of the two sets of windings trying to align themselves. The

fundamental operating principles of all electromagnetic rotating machines are thus essentially

the same. As might be expected from inspection of the individual structural details and

electrical interconnections, the details of analysis for synchronous, d-c, and induction

113 PE-IDM.601(B)




machines will follow diverging branches on the basic trunk. The general strategy underlying

analysis, however, is the same for all types.

The quantities of primary interest in machinery analysis are generated and terminal

voltages, currents, torques, and speeds. The two basic relations for any machine are one forgenerated voltage in terms of flux density (or flux per pole) and speed, and one for

electromagnetic torque in terms of flux density (or flux per pole) and current. With these two

relations and the principles of electric-circuit theory and mechanics, any desired operating

conditions can be quantitatively investigated. The general strategy of steady-state machinery

analysis as it will be carried out in later chapters can be summarized briefly in the following

four steps.

1. Obtain from Faraday´s law an expression for generated emf or counter emf. This

evaluation requires knowledge of the flux-density waveform in the machine and hence

demands examination of the flux distribution.

2. Investigate and include factors causing difference between generated emf and

terminal voltage under load. One such factor is resistance of the armature winding. Another

condition which must be borne in mind is that the armature winding also creates a component

magnetic field, and the flux-linkage bookeeping must be complete in this respect to yield the

correct terminal voltage. This effect may be included in the evaluation of emf in the first step,

or it may be made part of the second step; analytical convenience is the deciding point. These

factors are usually represented by the parameters of equivalent electric circuits. Their

evaluation again requires knowledge of flux distribution, with emphasis on that for thearmature.

The equivalent of the foregoing two steps, plus accounting for magnetic core

losses, applies also to the transformer and constitutes the basis of its analysis.

3. Obtain an expression for electromagnetic torque or counter torque. In general, the

relation may be established through any of four approaches:

a. The energy-conversion principle may be applied. When the rotational emf is

evaluated in

the first step, the electromagnetic power created by it in conjuction with the

armature current may be formulated. This power may be equated to that

created by the electromagnetic torque in conjuction with the speed.

b. The Bli relation may be used for individual conductor torque, followed by

summation over the entire armature winding. Knowledge of flux distribution is

evidently required.

The torque may be evaluated from the angular rate of change of flux linkageswith the armature winding. Again knowledge of flux distribution is required.

PE-IDM.601(B) 114




c. The torque may be evaluated from field-energy considerations.

4. Appropriately include machine losses. Ordinarily such inclusion is accomplished

by taking account of i²r losses in evaluating electric powers, and of mechanical losses together

with hysteresis and eddy-current losses in evaluating mechanical powers.The general objetive for each machine is to obtain equivalent circuits so that the

techniques of circuit theory become available for the investigation of energy-conversion

phenomena.

In general, all four methods listed for evaluation of electromagnetic torque may be

applied to the basic machine types. wHile these methods all yield the same results, the

processes of applying the methods lead to different degrees and shades of insight into

machinery fundamentals. Expediency is also a consideration, for some methods may lead

more directly to the desired results in a specific case. The first method leads directly and

easily to a result but gives almost no insight into how torque is produced. It says, in effect,

that if the machine works, a certain relation must be satisfied. The second method constitutes

a more careful examination into the details of torque production in terms of the forces on

current-carrying conductors in magnetic fields; as such, it answers morefully the question of

how machines work. Since the torque relation is derivable from Faraday´s law and energy

conservation in constant-field-energy machines, the second method is the equivalent of the

first, but it is applied at more nearly a basic level. This torque relation is readily applicable

only to certain electromagnetic machines, however, and therefore the second method does notreveal the fundamental aspects common to all forms of rotating electromagnetic machines.

The fourth method is the most fundamental of the approaches but also the most

difficult to apply. It is based on a relation applicable to all electromechanical energy-

conversion devices.

D-C Machines

The basic factors determining the behavior of d-c machines differ in two important

rrespects from those in the induction and synchronous machines: the torque angle is fixed bythe brush axis, normally at the optimum value of 90°; and, as viewed from the brushes, the d-c

values of generated emf and terminal voltage differ only by the voltage drop in the armature

resistance. Variation of electromagnetic torque is therefore determined only by variation of

the rotor and stator field strengths, and the variations in generated or terminal voltage may

readily be traced from similar considerations. Variation of rotor and stator field strength with

changing load depends on the method of connecting the field or stator circuit.

In the shunt motor the stator or field current is determined by the impressed voltage

and the field resistance and is independent of motor load. The flux per stator pole is then verynearly constant in normal operation. (It may decrease slightly with load because of a usually

small demagnetizing effect of increased armature current). Consequently, increased torque

115 PE-IDM.601(B)




must be accompanied by a very nearly proportionalincrease in armature mmf and armature

current and hence by a small decrease in counter emf to allow this increased current through

the small armature resistance. Since counter emf is determined by flux and speed. Like the

squirrel-cage induction motor, the shunt motor is substantially a constant-speed motor having

about 5 per cent drop in speed from no load to full load. Starting torque and maximum torqueare limited by the armature current that can be commutated successfully.

An outstanding advantage of the shunt motor is ease of speed control. With a rheostat

in the shunt-field circuit, the field current and flux per pole may be varied at will, and

variation of flux causes the inverse variation of speed to maintain counter emf approximately

equal to the impressed terminal voltage. A maximum speed range of about 4 or 5 to1 may be

obtained by this method, the limitation again being commutating conditions. By variation of

the impresses armature voltage, very wide speed ranges may be obtained.

In the series motor increase in load is accompanied by increases in the armature

current and mmf and the stator field flux (provided the iron is not completely saturated).

Because flux increases with load, speed must drop in order to maintain the balance between

impressed voltage and counter emf; moreover, the increase in armature current caused by

increased torque is smaller than in the shunt motor because of the increased flux. The series

motor is therefore a varying-speed motor with a markedly drooping speed-load. For

applications requiring heavy torque overloads, this characteristic is particularly advantageous

because the corresponding power overloads are held to more reasonable values by the

associated speed drops. Very favorable starting characteristics also result from the increase influx with increased armature current.

In the compound motor the series field may be connected either cumulatively, so that

its mmf adds to that of the shunt field, or differentially, so that it opposes. The differential

connection is very rarely used. A cumulatively compounded motor will have a speed-load

characteristic intermediate between those of a shunt and a series motor, the drop of speed

with load depending on the relative number of amper-turns in the shunt and series fields. It

does not have the disadvantage of very high light-load speed associated with a series motor,

but it retains to a considerable degree the advantages of series excitation.

In a d-c motor, the electromagnetic torque is, of course, in the direction of rotation of

the armature. The voltage Ea generated in the armature is smaller than the terminal voltage.

For operation as a generator, Ea is larger than the terminal voltage, and the relative direction

of current through the armature winding is reversed. Because of this reversal, both the

armature mmf and the electromagnetic torque reverse, the latter becoming a counter torque

opposing rotation. If the machine were connected to a d-c system capable of either absorbing

or supplying power, it would supply power to that system when it was driven so that the

generated voltage Ea exceeded the terminal voltage. If the mechanical torque were removed,

the armature would slow down under the influence of the counter electromagnetic torque until Ea became smaller than the terminal voltage. Reversal of the electromagnetic torque and

PE-IDM.601(B) 116




steady operation as a motor would follow, with the electromagnetic torque just sufficient to

overcome rotational losses.

Any of the three excitation methods may also be used for generation. Such generators

are called self-excited generators and require residual magnetism in the iron core for theinitial appearance of voltage. In addition, the field may be separately excited from an external

d-c source. Because constant-voltage power systems are the rule, series generators are very

seldom used. Normally, an overcompounded generator is operated with its no-load voltage set

at the rated value and hence with a greater full-load voltage, the increment compensating for

increased resistance drop in the feeder between the generator terminals and the load. If the

series field is so adjusted that full-load and no-loaad voltages are equal, the generator is flat-

compounded; if the full-load voltage is lower, it is undercompounded.

Synchronous Machines

A synchronous machine is an a-c machine whose speed under steady-state conditions

is proportional to the frequency of the the current in its armature. At synchronous speed, the

rotating magnetic field created by the armature currents travels at the same speed as the field

created by the field current, and a steady torque results.

Stripped down to its essentials, the workings of a symmetrical polyphase sybchronous

machine are rather simple. The d-c excited field winding creates a magnetic field rotating with

the rotor. Balanced, polyphase armature currents also create a component magnetic field

which rotates around the air gap, travelling through a mechanical angle equal to the anglesubtended by two adjacent poles in a time corresponding to one cycle. If the rotor is turning at

this speed, the component stator and rotor fields are stationary with respect to each other and a

steady torque is produced by their interaction. The resultant air-gap flux is produced by the

combined effect of the field and armature curents.

A synchronous machine has two outstanding characteristics: (1) the constancy of its

speed when operated at constant frequency, and (2) its ability to accommodate itself to

operation over a wide range of power factor.

The first characteristic is a result of the relation between the speed of the rotating

magnetic field produced by its armature currents and the frequency of these currents. Only at

this speed are the conditions for the production of steady, useful torque fulfilled. Although the

speed may differ momentarily from synchronous speed, as during the transient period of

adjustment from one steady-sate operating condition to another, the average steady-state

speed must be constant. The machine accommodates itself to changes in shaft torque by

adjusting its torque angle. The electromagnetic torque on the rotor acts in a direction to urge

the fields poles into alignment with the rsultant air-gap flux wave. For generator action, the

field poles must be driven ahead of the resultant air-gap flux wave by the forward torque of a prime mover, while for motor action the field poles must be dragged behind the resultant air-

117 PE-IDM.601(B)




gap flux wave by the retarding torque of a shaft load. It is as if the field poles were attached to

the rotating resultant air-gap flux wave by elastic bands.

The second oustanding characteristic (the adjustability of power factor) is a

consequence of the fact that the resultant mmf crreating the air-gap flux is the combined effectof a-c magnetizing current in the armature and d-c excitation in the field winding. Adjustment

of the field current therefore results in compensating changes in the magnetizing reactive kva

in the armature. Thus an overexcited synchronous motor operates at a leading power factor.

Alternatively, it may be said that an overexcited synchronous motor is a generator of lagging

reactive kva. Because of the economic importance of power factor, the ability of a

synchronous motor to operate a t a leading power factor is a valuable asset. The adjustability

of power factor usually is the chief reason for choosing a synchronous motor instead of an

induction motor.

The equivalence of synchronous generators and motors as sources of reactive kva

gives rise to amethod of thinking which is a value to the power-system engineer, who is faced

with the problem of supplying prescribed amounts of lagging reactive kva to his system loads.

He recognizes that, within certain limits, economic rather than technical factors can control

the location of the excitation needed to furnish the lagging reactive kva. It may be inrtoduced

in the generator fields, in the fields of synchronous motors or condensers, or by way of static

capacitors connected at strategic points.

With a physical picture of the internal workings in terms of rotating magnetic fields as

a background, the next step in our development of synchronous-machine theory is to showthat from the viewpoint of its armature circuits a synchronous machine operating under

balanced polyphase conditions can be represented on a per-phase basis by a very simple

equivalent circuit comprising an internal emf in series with its armature resistance and an

inductive reactance. The internal emf is the excitation voltage. The reactance is the

synchronous reactance. It accounts for the voltages induced in the reference phase by

balanced polyphase armature currents. The synchronous reactance is derived by replacing

theeffect of the rotating armature-reaction flux wave by a reactance Xφ, called the

magnetizing reactance. Flux linkages with the reference phase caused by component fluxes

wich are not included in the armature reaction, such as slot and coil-end leakage and space-

harmonic rotating fields, are accounted for by the armature leakage reactance X l. The

synchronous reactance is the sum of the magnetizing and leakage reactances.

The unsaturated synchronous reactance can be found from the results of an open-

circuit and a short-circuit test. These test methods are a variation of a testing technique

applicable not only to synchronous machines but also to anything whose behavior can be

approximated by a linear equivalent circuit to which Thévenin´s theorem applies. From the

Thévenin-theorem viewpoint, an open circuit test gives the internal emf, and a short-circuit

test gives information regarding the internal impedance. From the more specific viewpoint ofelectromagnetic machinery, an open-circuit test gives information regarding excitation

PE-IDM.601(B) 118




requirements, core losses, and (for rotating machines) friction and windage losses; a short-

circuit test gives information regarding the magnetic reactions of the load current, leakage

impedances, and losses associated with the load current such as copper and stray load losses.

The only real complication arises from the effects of magnetic nonlinearity, effects which can

be taken into account approximately by considering the machine to be equivalent to anunsaturated one whose synchronous reactance is empirically adjusted for saturation.

In terms of the equivalent circuit, the prediction of the steady-sate synchronous-

machine characteristics becomes merely a study of power flow through a simple impedance

with constantor easily determinable voltages at its ends. Study of the maximum-power limits

for short-time overloads is merely a special case of the limitations on power flow through an

inductive impedance. The power flow through such an impedance can be expressed

conveniently in terms of the voltages at its sending and receiving ends and the phase angle

between these voltages, when the resistance is neglected. On the basis of this equation, theinternal phenomena in synchronous machines are those of power flow through the

magnetizing reactance Xφ with the air-gap voltage E r at one end and the excitation voltage Eƒ

at the other, the time-phase angle between these voltages being the internal torque angle

between the interacting magnetic fields within the machine. The result so obtained is

completely in agreement with the basic torque equation, on which our theory of torque

production in rotating machines is based.

When synchronous generators are operated in parallel, they must be running in

synchronism. Consequently the system frequency and the division of active power amongthem depend on their prime-mover throttle settings and speed-power characteristics.

Generator field control affects system voltage and the division of reactive kva among

paralleled alternators. Unlike paralleled d-c generators, however, field control has essentially

no effect on the division of the active-power load.

Although we have simplified the synchronous machine considerably in this chapter,

nevertheless the results which we have obtained here enable us to predict the normal steady-

state characteristics with sufficient accuracy for many purposes. When more accurate results

are required, the effects of magnetic saturation and of salient poles must be properly

accounted for.

119 PE-IDM.601(B)






CHAPTER 15

DAMAGES. NOMENCLATURE

Vocabulary

Adjust, to Ajustar

Bend, to Doblar

Blow Golpe

Break, to Romper

Breakage Rotura

Breakdown Avería

Burst, to Estallar, reventar

Chock, to Obturar, atascar

Chip, to Astillar

Clog, to Atascar

Corrosion Corrosión

Crumble, to Desmoronarse

Crush, to Romper por compresión

Damage Daño

Deformation Deformación

Disconnect, to DesconectarDismantle Desmontar, desarmar

Erosion Erosión, desgaste

Fouling Incrustaciones

Fracture Fractura

Friction Rozamiento

Impact Golpe

Knock, to Golpear

Leak, to Tener fugas, gotear

Leak FugaLoose, to Aflojar, soltar

Noise Ruido

Overhold Revisión

Overload, to Sobrecargar

Oxidation Oxidación

Pounding Golpeo, martilleo

Scouring action Acción abrasiva

Split, to Partir, rajar

Spoil, to Estropear

Stick, to Agarrotarse, atascarse

121 PE-IDM.601(B)




Stop up, to Obstruir, tapar, cegar

Stopped up Obstruido

Rub, to Rozar

Vibrate, to Vibrar

Vibration Vibración, trepidaciónWear, to Desgastar

Wear out, to Desgastar

Wearing Desgaste, deterioro

Worn Gastado

Expressions of Damages

What is the trouble with the engine?. ¿Qué avería tiene la máquina?.

The engine cannot be started. El motor no se puede poner en marcha.

The starting pressure ir too low. La presión de arranque es demasiado baja.

The piston of the sliding valve is stuck. El émbolo de la corredera está

enganchado.

The spring is broken. El muelle está roto.

The valve must be dismantle. La válvula debe desmontarse.

The spring must be changed. El muelle debe cambiarse.The engine resistance is great. La resistencia del motor es muy grande

The bearings are bad adjusted. Los cojinetes están mal ajustados.

There is an excessive friction. Hay demasiado rozamiento.

The exhaust valve is not airtight. La válvula de escape no es estanca.

The rings are worn out. Los aros están gastados.

No combustion is produced. No se produce combustión.

The fuel does not reach the combustion No llega el combustible a la cámara de

chamber. combustión.

The fuel pipe is stopped up. La tubería de combustible está atascada.

The device is not properly set up. El mecanismo no está bien ajustado.

The fuel pump is badly adjusted. La bomba de combustible está mal

regulada.

There is no combustion in some of the En algunos de los cilindros no se producecylinders. la combustión.

PE-IDM.601(B) 122




The fuel contains water. El combustible contiene agua.

There is no combustion in one cylinder. No hay combustión en un cilindro.

There is air in the fuel pump. La bomba de combustible tiene aire.

The fuel pump does not maintain the pressure. La bomba de combustible no mantiene la

presión.

The fuel pump has leaks. La bomba de combustible tiene fugas.

The injector must be changed. Debe cambiarse el inyector.

The nozzle is stopped. La tobera está obstruida.

Functions of damage controlAboard ship, the overall damage and casualty control function is composed of two

separated but related phases: the engineering casualty control phase and the damage control

phase. The engineer officer is responsible for both phases.

The engineering casualty control phase is concerned with the prevention, minimization,

and correction of the effects of operational and battle casualties to machinery, electrical

systems, and piping installations, to the end that all engineering services may be maintained in

a state of maximum reliability under all conditions of operation. Engineering casualty control

is handled almost entirely by personnel of the engineering department.The damage control phase, on the other hand, involves practically every person aboard

ship. The damage control phase is concerned with such things as the preservation of stability

and watertight integrity, the control of fires, the control of flooding, the repair of structural

damage, and provide countermeasures in the event of nuclear, biological, and chemical attack.

The broad objectives of damage control are to prevent, minimize, and correct the effects

of operational and battle damage to the ship and to personnel in order to maintain the

firepower, mobility, maneuverability, stability, and bouyancy of the ship. In other words,

damage control aims at maintaining the ship and its personnel in such a condition that the shipcan carry out its assigned mission.

The damage control organization is the means by which the objectives of damage

control can be attained. In fact, organization is the key of successful damage control. The

damage control organization establishes standard procedures for handling various kinds of

damage and its sets up training procedures so that every person should immediately know

what to do in each emergency situation.

Both the preventive and the corrective aspects of damage control are vitally important.

The preventive aspects of damage control require the efforts of all deparments in establishingmaterial conditions of readiness, in training personnel, and in maintaining the ship in the best

possible condition to resist damage. To achieve this ends, the ship´s damage damage control

123 PE-IDM.601(B)




organization must be coordinated with other elements of the ship´s organization. In each

department, therefore, specific damage control duties must be assigned to individuals in each

division; this includes the designation of a division damage control petty officer. The

corrective (or action) aspects of damage control requires the damage control battle

organization to promptly restore the offensive and defensive capabilities of the ship.

As previously noted, the engineer officer is responsible for damage control. The damage

control assistant (DCA), who is under the engineer officer, is responsible for establishing and

maintaining an effective damage control organization. Specifically, the DCA is responsible

for the prevention and correction of damage, the training of ship´s personnel in damage

control, and the operation, maintenance, and care of certain machinery, drainage, and piping

systems not specifically assigned to other departments or divisions.

There are actually two damage control organizations: the damage control administrative

organization and the damage control battle organization. The damage control administrativeorganization is an integral part of the engineering department organization. The damage

control battle organization includes damage control central and various repair parties. The

damage control battle organization varies somewhat from one ship to another, depending

upon the size, type, and mission of the ship. However, the same basic principles apply to all

damage control organizations.

The primary purpose of damage control central is to collect and compare reports from

the various repair stations in order to determine the condition of the ship and the corrective

action to be taken. The damage control assistant, at his battle station in damage controlcentral, is the nerve center and directing force of the entire damage control organization. He is

assisted in damage control central by a stability officer, a casualty board operator, and a

damage analyst. In addition, representatives of the various divisions of the engineering

department are assigned to damage control central.

In damage control central, repair party reports are carefully checked so that immediate

action can be taken to isolate damage systems and to make emergency repairs in the most

effective manner. Graphic records of the damage are made on various damage control

diagrams and status boards, as the reports are received. For example, reports on flooding are

marked up, as they come in, on a status board that indicates liquid distribution before damage.

With this information, the stability and bouyancy of the ship can be estimated and the

necessary corrective measures can be determined.

If damage control central is destroyed or is for other reasons unable to retain control, the

repair stations, in designated order, take over the functions of damage control central.

Repair parties are assigned to specifically located stations. Repair stations may be

further subdivided into unit patrols to permit dispersal of personnel and a wide coverage of

the assigned areas. Provisions are made for passing the control of each repair station down

through the officers, petty officers, and nonrated men so that no group will ever be without a

leader.

PE-IDM.601(B) 124




The number of repair parties in the damage control organization depends upon the size,

type, and mission of the ship.

Maintaining watertight integrity

The success of damage control depends in part upon the proper utilization of the

watertight integrity features of the ship. Compartmentation is a major watertight integrity

feature of a naval ship. The ship is divided into compartments to control flooding, to

strengthen defense against NBC attack, to segregate activities, to provide underwater

protection by means of tanks and voids, to strengthen the structure of the ship, and to provide

a means of controlling buoyancy and stability. Most large combatant ships have an armor belt

to protect vital machinery spaces. In some cases, where an increase in armor plating would

reduce the ship´s speed or have an adverse effect on the operation of the ship (as in the case of

aircraft carriers), compartmentation is increased to compensate for the reduction of armor.Every naval ship is divided by decks and bulkheads both above and below the waterline

into as many watertight compartments as are compatible with the mission of the ship. In

general, increasing the amount of compartmentation increases the ship´s resistance to sinking.

The original watertight integrity of a naval ship is established when the ship is built.

This original watertight integrity may be reduced or destroyed through enemy actions, storm

damage, collision, stranding, or negligence. It is the responsability of the engineer officer to

see that the ship´s watertight integrity is not impaired through negligence and that any

impairment is corrected as rapidly as possible. To ensure the maintenance of watertightintegrity, a thorough system of inspections and tests is prescribed.

Material conditions of readiness refers to the degree of access and system closure to

limit the extent of damage to the ship. Maximum closure is not maintained at all times

because it would interfere with the normal operation of the ship. For damage control

purposes, naval ships have three material conditions of readiness, each condition representing

a different degree of tightness and protection. The three material conditions of readiness are

called X-RAY, YOKE, and ZEBRA. These titles, which have no connection with the

phonetic alphabet, are used in all spoken and written communications concerning material

conditions.

Condition X-RAY, which provides the least protection, is set when the ship is in no

danger from attack, such as when it is at anchor in a well protected harbor or secured at a

home base during regular working hours.

Condition YOKE, which provides somewhat more protection tha condition X-RAY, is

set and maintained at sea. It is also maintained in port during wartime and at other times in

port outside of regular working hours.

Condition ZEBRA is set before going to sea or entering port, during wartime. It is alsoset immediately, without further orders, when manning general quarters stations. Condition

125 PE-IDM.601(B)




ZEBRA is also set to localize and control fire and flooding when not at general quarters

stations.

DAMAGE CONTROL CENTRAL “F-100”.

Fundamentals of firefighting

Fire is a constant potential hazard aboard ship. All possible measures must be taken to

prevent the occurrence of fire or to bring about its rapid extinguishment. In many cases, fires

occur in conjunction with other damage, as a result of enemy action, weather, or accident.

Unless fire is rapidly and effectively extinguished, it may easily cause more damage than the

initial casualty. In fact, fire may cause the loss of a ship even after the original damage has

been repaired or minimized.

Fire, also called burning or combustion, is a rapid chemical reaction that results in the

release of energy in the form of light and noticeable heat. Most combustion involves veryrapid OXIDATION—that is, the chemical reaction by which oxygen combines chemically

with the elements of the burning substance.

PE-IDM.601(B) 126




Even when oxidation proceeds very slowly, as in the case of a piece of iron that is

rusting, a small amount of heat is generated. However, this heat is usually dissipated before

there is any noticeable rise in the temperature of the material being oxidized. With certain

types of materials, slow oxidation can turn into fast oxidation (fire) if the heat is not

dissipated. When this occurs, we say that SPONTANEOUS COMBUSTION has occurred.Such things as rags or papers soaked with animal or vegetable fats or with paints or solvents

are particularly subject to spontaneous combustion if they are stowed in confined spaces

where the heat of oxidation cannot be dissipated rapidly enough.

In order to have a combustible fuel or substance take fire, it must have an ignition

source and it must be hot enough to burn. The lowest temperature at which a flammable

substance gives off vapors that will burn when a flame or spark is applied is called the

FLASH POINT. The FIRE POINT, which is usually a few degrees higher than the flash point,

is the temperature at which the fuel will continue to burn after it has been ignited. The AUTO-IGNITION or SELF-IGNITION POINT is the lowest temperature to which a substance must

be heated to give off vapors that will burn without the applicationof a spark or flame. In other

words, the auto-ignition point is the temperature at which spontaneous combustion occurs.

The auto-ignition point is usually at a much higher temperature than the fire point.

The range between the smallest and the largest amounts of vapor in a given quantity of

air that will burn or explode when ignited is called the FLAMMABLE RANGE or the

EXPLOSIVE RANGE. Say, for example, that a substance has a flammable or explosive range

of 1 to 12 percent. This means that fire or explosion can occur if the atmosphere contains

more than 1 percent but less than 12 percent of the vapor of this substance. In general, the

percentages referred to in connection with flammable or explosive ranges are percentages by

volume.

It should be apparent by now that a fire cannot exist without three things: (1) a

combustiblematerial, (2) a sufficiently high temperature, and (3) a supply of oxygen. Because

of these three requirements, the process of fire is sometimes regarded as being a triangle with

the three sides consisting of of FUEL, HEAT, and OXYGEN. As we will see presently, the

control and extinguishment of fires is generally brought about by eliminating one side of the

fire triangle—that is, by removing fuel, heat, or oxygen.

Fires are classified according to the nature of the combustibles (or fuels) involved. The

classification of any particular fire is of great importance, since it determines the manner in

whiich the fire must be put out. Fires are classified as being class A, class B, class C, or class

D fires.

CLASS A fires are those occurring in such ordinary combustible materials as wood,

cloth, paper, upholstery, and similar materials. Class A fires are usually extinguished with

water, using high or low velocity fog or solid streams. Class A fires leave embers or ashes and

they must always be overhauled.

127 PE-IDM.601(B)




CLASS B fires are those occurring in the vapor-air mixture over the surface of

flammable liquids such as gasoline, jet fuels, diesel oil, fuel oil, paints, thinners, solvents,

lubricating oils, and greases. Dry chemical, foam, light water, carbon dioxide, or water fog

can be used to extiguish class B fires; the choice of agent depends upon the circunstances of

the fire.

CLASS C fires are those occurring in electrical equipment. Nonconducting

extinguishing agents such as dry chemicals and carbon dioxide are used for extinguishing

class C fires. Carbon dioxide is the preferred extinguishing agent because it leaves no residue.

CLASS D fires are those occurring in combustible metals such as magnesium,

titanium, and sodium. Special techniques have been developed for the control of this type of

fire.

In general, fires may be extinguished by removing one side of the fire triangle (fuel,heat, or oxygen) or by slowing down the rate of combustion. The method or methods of

extinguishment used in any specific instance depend upon the classification of the fire and the

circumstances surrounding the fire.

Although it is not usually possible to actually remove the fuel in order to control a fire,

there may be circumstances in which fuel removal is possible. If part of the fuel that is near or

actually in a fire can safely be jettisoned over the side, this should be done as soon as

possible. Damage control parties must stand ready at all times to shift combustibles to safe

areas and to take whatever measures that are possible to prevent additional fuel from coming

into contact with the fire. In particular, supply valves in gasoline and oil lines must be closedimmediately.

If enough heat can be removed by cooling the fuel to a temperature below that at

which it will support combustion, the fire will go out.

Heat may be transferred in three ways: by radiation, by conduction, and by convection.

In the process known as radiation, heat is radiated in all directions; it is radiated heat that

causes you to feel hot when you stand near an open fire. In conduction, heat is transferred

through a substance or from one substance to another by direct contact from molecule to

molecule; thus a thick steel bulkhead with a fire on one side conducts heat from the fire to theadjoining compartments. In convection, the heated air and other gases rising from a fire bring

heat to all combustible materials within reach. Heat transfer by convection is a particular

danger in the case of ventilation systems, which may carry heated gases to places that are very

far removed from the original fire.

To eliminate the heat side of the fire triangle, it is necessary to cool the fire by

applying something that will absorb the heat. Although some other materials serve this

purpose, water is the most commonly used cooling agent. Water may be applied in the form

of a solid stream, as a fog, or incorporated in foam. The way in which the water or othercooling agent is applied depends upon the nature of the fire.

PE-IDM.601(B) 128




The third component of the fire triangle, oxygen, is difficult to control because we

obviously cannot remove oxygen from the atmospheric air that normally surrounds a fire.

However, oxygen can be diluted or displaced by other substances that are noncombustible, so

that extinguishment of the fire will occur.

If fire occurs in a closed space, it can be extinguished by diluting the air with carbon

dioxide (CO²) gas. This dilution of the air must proceed to a certain point before the flames

are extinguished, but no fire can exist after this point has been reached. In general, a large

enough volume of CO² must be used to reduce the oxygen content to 15 percent or less. The

amount of oxygen normally present in air is about 21 percent.

Steam and foam are also used to keep oxygen from reaching the burning materials,

thus smothering the fire.

Dry chemical fire extinguishing agents extinguish fires by a process that is not quitethe same as removing one side of the fire triangle. It is believed that these agents achieve their

extinguishing effects by interfering with the combustion reaction.

No matter what basic method of fire extinguishment is used, it must be used very

rapidly if the fire is to be brought under control. Most fires start from quite small points of

ignition, but they grow by leaps and bounds. If a fire is to be successfully extinguished, it

must be done as rapidly as possible. Even a slight delay may cause the fire to grow beyond

control with the available equipment.

When a substance burns, a number of chemical reactions occur. These reactions resultin the formation of flame, heat, and smoke. They also result in the production of a number of

gases and other combustion products, and frequently they cause a reduction in the amount of

oxygen available for breathing. All of these effects of fire are vitally important to the

firefighter, who must be prepared to protect himself against them.

In order to avoid injury or loss of life, it is necessary to protect against flame, heat, and

smoke. Before entering a compartment or area where a fire exists, the firefighter should be in

proper dress. Pant legs should be tucked into socks. The collar should be buttoned. The

firefighter should wear asbestos gloves, a helmet, a head lamp, and an oxygen breathing

apparatus (OBA). The flame and the heat from a fire are intense, but proper dress will help to prevent burns. The smoke will make it hard to see and hard to breathe, but the OBA and the

head lamp will help the firefighter to cope with these problems.

Some of the gases produced by a fire are toxic (poisonous) and others are dangerous in

other ways, even though they are not toxic. Some of the gases commonly produced by a fire

are discussed briefly in the following paragraphs.

CARBON MONOXIDE is produced when fire occurs in a closed compartment or

under other conditions where there is not enough oxygen for the complete combustion of all

the carbon in the burning material. Carbon monoxide, which has the chemical formula CO, isa colorless, odorless, tasteless, and nonirritating gas. It is DEADLY even in small

129 PE-IDM.601(B)




concentrations. A person who is exposed to a concentration of 1.28 percent CO in air will

become unconscious after two or three breaths and will probably die in 1 to 3 minutes.

Carbon monoxide is also very dangerous because of its very wide explosive range. If carbon

monoxide is mixed with air in the amount of 12.5 to 74 percent by volume, an open flame or

even a spark will set off a violent explosion.

CARBON DIOXIDE (CO²) is a colorless, odorless gas that is formed by the complete

combustion of the carbon in burning materials. CO² is not poisonous; its main danger to the

firefighter is that an atmosphere of carbon dioxide does not provide oxygen to breathe, and

asphyxiation may result. The danger of asphysiation is particularly great because carbon

dioxide, being colorless and odorless, does not give any warning of its presence even when it

is present in dangerous amounts. Carbon dioxide does not support combustion and it does not

form explosive mixtures with any substances; because of these characteristics, it is very useful

as a fire extinguishing agent. It is also used for inerting fuel oil tanks, gasoline tanks, andsimilar spaces.

HYDROGEN SULFIDE (H2S) is a colorless gas. In low concentrations, hydrogen

sulfide smells like rotten eggs. Hydrogen sulfide is generated in some fires; it also occurs as

the result of the rotting of foods, cloth, leather, and other organic materials. Air that contains

4.3 to 46 percent hydrogen sulfide is violently explosive in the presence of flame. Hydrogen

sulfide is extremely poisonous is breathed, even in concentrations as low as 0.01 percent.

Acute poisoning results from breathing hydrogen sulfide in larger concentrations; rapid

unconsciousness, cessation of breathing, and death can occur in a very few minutes from

breathing an atmosphere that contains from 0.07 to 0.10 percent hydrogen sulfide.

When a fire occurs in a closed compartment or similar space, an inadequate supply of

oxygen for breathing may result. An enormous amount of oxygen is used by the fire itself,

leaving relatively little oxygen for men to breathe. The amount of oxygen normally present in

the air is 21 percent, and human beings breathe and work best with this amount of oxygen.

When there is only 17 percent oxygen in the atmosphere, people breathe a little faster and

deeper. When there is only 15 percent oxygen, a person is likely to become dizzy, having a

buzzing in his ears, have a rapid heartbeat, and have a headache. When the oxygen content

falls to 9 percent, unconsciousness may occur. Death is likely to result when the oxygencontent of the atmosphere is 7 percent or less.

Effects of nuclear explosions

Nuclear warfare is that in which explosions are produced by the processes of nuclear

fission or nuclear fusion. Nuclear explosions may be achieved with bombs or with warheads

in guided missiles, torpedoes, rockets, and similar remote control weapons.

Nuclear weapons cause destruction to materials by blast or shock or heat; they cause

casualties to personnel by blast, heat, or nuclear radiation. Except for the nuclear radiation,

PE-IDM.601(B) 130




nuclear weapons are similar to but immensely more powerful than ordinary high explosive

weapons.

The effects of nuclear explosions vary, depending upon the energy yield of the

weapon, the manner in which the weapon is exploded, and other factors.The energy yield of a nuclear weapon is described in terms of the amount of TNT that

would be required to release a similar amount of energy. Thus a nuclear weapon capable of

releasing an amount of energy equivalent to the energy released by 20,000 tons of TNT is said

to be a 20-kiloton weapon. A nuclear weapon capable of releasing an amount of energy

equivalent to the energy released by 1,000,000 tons of TNT is said to be a 1-megaton weapon.

The bombs dropped on Japan in 1945 were in the 20-kiloton range. The weapons variously

referred to as hydrogen bombs, H-bombs, fusion bombs, or thermonuclear bombs are in the

megaton range.

The general effects of shock, blast, heat, and nuclear radiation occur in any nuclear

explosion. However, the specific details of these effects vary according to the location of the

explosion. In considering the effects of nuclear explosions, then, it is necessary to identify the

explosions as (1) airbursts, (2) high-altitude bursts, (3) surface bursts, and (4) subsurface

bursts. The information on the effects of the various types of bursts is based on observations

made during the Japan explosions and during various test explosions.

Airburst. Almost immediately after a nuclear explosion, the weapon residue

incorporates material from the surrounding medium and forms an intensely hot and luminous

mass, roughly spherical in shape, called a fireball.

An airburst is defined as one in which the weapon is exploded in the air at such a

height that the fireball does not touch the surface of the earth. For example, in the explosion

of a 1-megaton weapon, the fireball may grow until it is nearly 7200 feet (1.3 miles) across.

This means that, for a 1-megaton weapon, the explosion must occur at least 3600 feet above

the earth´s surface if it is to be called an airburst. The diameter of a 20-kiloton weapon fireball

is aproximately 900 feet.

The interior temperature of the fireball is so high (tens of millions of degrees F, as

compared with a maximum of 9000°F in a conventional high-explosive weapon) that allsubstances present are in the form of vapor. Substances present include radiactive fission

fragments, unfissioned nuclear material, neutron induced gamma radiation, and materials that

were in the vicinity of the explosion. As the tenperature falls, this vapor condenses to form a

cloud. In addition, strong inflowing winds created by the rising fireball force up dust and

other debris from the earth´s surface, if the burst occurs near the earth´s surface.

Consequently, there is formed a high, expanding column of dust that rises to a height

commensurate with the energy of the bomb. If the cloud reaches 5 to 10 miles above the earth,

there is a tendency for it to cease rising and to spread out laterally, producing the

characteristic cauliflower-shaped cloud. The size of the fireball varies according to the size of

the nuclear weapon.

131 PE-IDM.601(B)




As mentioned previously, the sudden liberation of energy after an explosion causes a

considerable increase in temperature and pressure, so that all materials present are converted

into hot compressed gases or vapors. Because these gases are at high temperatures and

pressures, they expand rapidily and thus initiate a pressure wave, called a blast wave. This

blast wave develops a fraction of a second after the explosion and moves outward in alldirections from the fireball, at an initial speed greater than the speed of sound. As the fireball

expands and cools, its rate of growth slows, allowing the blast wave to break away from the

fireball and continue on its own momentum. This blast wave is measured in static

overpressure, which is pressure over and above atmospheric pressure. The blast wave and its

accompanying strong winds are responsible for the physycal damage caused by an airburst.

High-altitude burst. A high-altitude burst is defined as one in which the point of

detonation is at an altitude of more than 100,000 feet. Because the air is less dense at high

altitudes, the effects of a high-altitude burst are somewhat different than the effects of anairburst. In a high-altitude burst, a very large proportion of the energy is released in the form

of heat.

Surface burst. A surface burst is one that occurs at or slightly above the actual surface

of the land or water. In a surface burst, the fireball actually touches the surface. The heat

developed in a surface burst is almost the same as that developed in an airburst. The overall

destruction from the blast wave is somewhat less in a surface burst than in an airburst because

some of the energy is used up in vaporizing the materials on the surface and, in the case of a

surface burst over land, in forming a crater. Targets close to ground zero are completely

destroyed by a surface burst, but the effects of an airburst. A surface burst is likely to result in

much greater fallout than an airburst.

Subsurface burst. Underground burst and underwater bursts are known as subsurface

bursts. When a subsurface underground burst occurs, there is of course a strong shock wave in

the earth. If the detonation occurs underground but rather near the surface, the fireball may be

visible as it breaks through the surface. In general, thermal radiation (heat) is absorbed by the

soil and rocks and so does not represent a significanthazard in an underground burst. A

radioactive cloud resulting from an uncontained underground burst contains a large amount of

soil, rock, and other material: therefore, a considerable amount of radioactive fallout is to beexpected from an underground burst that breaks through the surface.

The effects of a subsurface underwater burst depend upon the energy yield of the

weapon, the distance below the surface at which the detonation occurs, and the depth an area

of the body of water. The description given here is chiefly based on observations made at the

Baker test at Bikini in 1946. In this test, a 20-kiloton nuclearweapon was detonated well

below the surface of a lagoon that was 200 feet deep. These conditions may be regarded as

corresponding to a shallow underwater burst.

In an underwater burst, a fireball is formed. However, this fireball is smaller than it isin an airburst. At the Baker test, water in the vicinity of the explosion was illuminated by the

PE-IDM.601(B) 132




fireball. Distortion caused by the water waves on the surface of the lagoon prevented a clear

view of the fireball. The luminosity persisted for a few thousandths of a second, and

disappeared as soon as the bubble of hot high pressure gases or vapors and steam constituting

the fireball reached the surface of the water. At this time, the gases were expelled and cooled

and the fireball was no longer visible.

If the depth of burst is not too great, the bubble remains essentially intact until it rises

to the surface of the water. At this point the steam and debris are expelled into the

atmosphere. Part of the shock wave passes through the surface into the air and, because of

high humidity, conditions are suitable for the formation of a condensation cloud known as the

Wilson cloud. The underwater shock wave travels about five times as fast as the blast wave

travels through air.

Damage zones. Unless distorted by other factors, the blast damage following a nuclear

explosion is usually confined to a circular area around ground zero, the point vertically belowor above the center of a burst of a nuclear weapon. For convenience, the four general areas are

designated as A,B,C, and D zones or rings. There are varying degrees of destruction within

these areas.

The A zone of damage is the central area immediately surrounding ground zero. This

area is usually one of total destruction in which neither personnel or ordinary buildings have

any chance of survival. Outside this area is the B zone, which is large belt of heavy damage.

The B zone is generally about three times as large as the A zone. Injuries to personnel and

structural damage would be severe but not total in the B zone. The C zone is a still largercircular belt of lesser damage surrounding the B zone. Injuries to personnel and physical

damage in this area would range from moderate to light. In the outer D zone, damage would

be light. Beyond the D zone, little or no damage would be sustained.

133 PE-IDM.601(B)




PE-IDM.601(B) 134




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