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Positive displacement pumpsPositive displacement pumpsPUMPS
DISPLACMENT DYNAMIC
RECIPROCATING ROTARY
DIAPGRAGM
PISTON, PLUNGER
GEAR
SCREW
VANE
LIQUID RING
ECCENTRIC
LOBE
STEAM-DOUBLE ACTING
POWER
CIRCUMFERENTIAL
PERISTALTIC
CharacteristicsCharacteristics
pulse with each strokepulse with each stroke self-priming self-priming pressure increases internal leakage pressure increases internal leakage
Positive displacement versus centrifugal Positive displacement versus centrifugal pumpspumps
Pressure Pressure dependencedependence
• Viscosity effectViscosity effect EfficiencyEfficiency
Rotary pumpsRotary pumps A Rotary pump is a positive displacement pump A Rotary pump is a positive displacement pump
consisting of a chamber containing gears, cams, screws, consisting of a chamber containing gears, cams, screws, vanes, plungers or similar elements actuated by relative vanes, plungers or similar elements actuated by relative rotation of the drive shaft & casing rotation of the drive shaft & casing
CharacteristicsCharacteristics::
1.1. time continuous liquid seal is maintained between the time continuous liquid seal is maintained between the inlet & the outlet ports inlet & the outlet ports
2.2. amount of liquid displaced by each revolution is amount of liquid displaced by each revolution is independent of speedindependent of speed
3.3. smooth and uniform Flow smooth and uniform Flow
Pumping action of rotary pumpsPumping action of rotary pumps::
Closed-to-outlet-open-to-inlet
Closed-to-outlet-closed-to-inlet
Open-to-outlet-Closed-to-inlet
For a good pumping actionFor a good pumping action::
The open to inlet (OTI) volume The open to inlet (OTI) volume should grow smoothly & should grow smoothly & continuously with pump rotation.continuously with pump rotation.
The closed to inlet & outlet (CTIO) The closed to inlet & outlet (CTIO) volume should remain constant with volume should remain constant with pump rotation.pump rotation.
The open to outlet (OTO) volume The open to outlet (OTO) volume should shrink smoothly & should shrink smoothly & continuously with pump rotation.continuously with pump rotation.
ECCENTRIC PUMPSECCENTRIC PUMPS
How the pump worksHow the pump works
BenefitsBenefits Operates with dry suction. Operates with dry suction. Simple to install. Simple to install. High suction lift. High suction lift. Constant capacity at varying heads. Constant capacity at varying heads. Single cover access. Single cover access. Simple to operate. Simple to operate. Remove the last drop from Remove the last drop from
containers. containers.
ApplicationsApplications Bilge pumpsBilge pumps Sludge pumpsSludge pumps Fuel oil pumpsFuel oil pumps Ballast pumpsBallast pumps Pressure systemsPressure systems Purification pumpsPurification pumps Low magnetic pumps (mine sweeper)Low magnetic pumps (mine sweeper) Black water pumps Black water pumps
Vane PumpsVane Pumps
Internal vane pumpsInternal vane pumps
Flexible vane pumpFlexible vane pump
Vane pump Advantages Vane pump Advantages Medium capacity Medium capacity Medium speed Medium speed Thin liquids Thin liquids Sometimes preferred for solvents, LPG Sometimes preferred for solvents, LPG Can run dry for short periods Can run dry for short periods Develops good vacuum Develops good vacuum
Vane pump DisadvantagesVane pump Disadvantages Can have two stuffing boxes Can have two stuffing boxes Complex housing Complex housing Not suitable for high pressures Not suitable for high pressures Not suitable for high viscosity Not suitable for high viscosity
Vane pump Applications Vane pump Applications Auto Industry - Fuels, Lubes, Auto Industry - Fuels, Lubes,
Refrigeration Coolants Refrigeration Coolants Barge Unloading Barge Unloading Bulk Transfer of LPG and NH3 Bulk Transfer of LPG and NH3 Chemical Process Industry Chemical Process Industry Ethanol/Alcohol Refining Ethanol/Alcohol Refining Fertilizer Production - CO Transfer Fertilizer Production - CO Transfer Lubrication Blending - Solvents, Oils Lubrication Blending - Solvents, Oils Power Generation - Fuels, Lubrication Power Generation - Fuels, Lubrication
Materials of ConstructionMaterials of Construction
Externals (head, casing, bracket)Externals (head, casing, bracket) - Cast iron, ductile iron, steel, and - Cast iron, ductile iron, steel, and stainless steel. stainless steel.
Vane, PushrodsVane, Pushrods - Viton®, Ryton®, - Viton®, Ryton®, PPS, carbon, Teflon®, and peek. PPS, carbon, Teflon®, and peek.
Liquid Ring PumpLiquid Ring Pump
componentscomponents
How the pump worksHow the pump works
BenefitsBenefits Simplified ConstructionSimplified Construction
All components are designed for 24 hour per day All components are designed for 24 hour per day continuous service under the most demanding industrial continuous service under the most demanding industrial conditions. conditions.
Environmentally CleanEnvironmentally CleanNo oil used for lubrication or sealing. No oil vapor No oil used for lubrication or sealing. No oil vapor discharged to the atmosphere. discharged to the atmosphere.
High Vacuum CharacteristicsHigh Vacuum CharacteristicsExclusive axial flow design permits efficient operation in the Exclusive axial flow design permits efficient operation in the full vacuum range from 0 to 29 inches of mercury (760-25 full vacuum range from 0 to 29 inches of mercury (760-25 Torr). Torr).
Advanced DesignAdvanced DesignEmploys mechanical seal and O-ring gaskets for zero Employs mechanical seal and O-ring gaskets for zero leakage. leakage.
Vibrationless OperationVibrationless OperationNo special foundations required. No special foundations required.
Constant PowerConstant PowerPower requirements are constant over the full vacuum Power requirements are constant over the full vacuum range. Non-overloading. range. Non-overloading.
Low MaintenanceLow MaintenanceNo metal-to-metal contact between rotating and stationary No metal-to-metal contact between rotating and stationary elements.elements.
Advantages:Advantages: Tolerate entrained liquids and solidsTolerate entrained liquids and solids Isothermal compression (for monomer Isothermal compression (for monomer
recovery, explosive gases)recovery, explosive gases) OilfreeOilfree Very safe for explosive gasesVery safe for explosive gases Simple design for corrosion resistant Simple design for corrosion resistant
materialsmaterialsDisadvantages:Disadvantages: High power absorbedHigh power absorbed Process fluid and auxiliary fluid are mixed-Process fluid and auxiliary fluid are mixed-
up / contaminatedup / contaminated
Peristaltic pumpPeristaltic pump
How the pump workHow the pump work
Peristaltic pump advantages:Peristaltic pump advantages: Hydraulically operated Hydraulically operated speed variationsspeed variations to meet all job to meet all job
demands.demands. Enables pumping of heavy, fibered, thick, and abrasive Enables pumping of heavy, fibered, thick, and abrasive
materials at high volumes.materials at high volumes. The pump's mechanical maintenance is limited to The pump's mechanical maintenance is limited to hose hose
wearwear.. Pumped material Pumped material does not come in contactdoes not come in contact with any with any
moving parts.moving parts. Dry runningDry running can occur without causing damage to the can occur without causing damage to the
pump.pump. Replacement of hoseReplacement of hose is quick and easy. is quick and easy. Pumping is Pumping is cleanlinesscleanliness
ApplicationsApplications Peristaltic pumps are used mostly in Peristaltic pumps are used mostly in chemical chemical
laboratorieslaboratories, but they can be used for injection of , but they can be used for injection of chemicals into small irrigation systems. chemicals into small irrigation systems.
Peristaltic pumps have a variety of Peristaltic pumps have a variety of medical applicationsmedical applications. . They can be used to add They can be used to add nutrients to bloodnutrients to blood, to force , to force blood through filters to clean it, or to move blood through blood through filters to clean it, or to move blood through the body and lungs during the body and lungs during open heart surgery open heart surgery
Gear PumpGear Pump
transfer liquids both of high and low viscosity transfer liquids both of high and low viscosity are used in the lubrication circulation systems of are used in the lubrication circulation systems of
various shipboard installations various shipboard installations uniform delivery, simple manufacture, uniform delivery, simple manufacture,
comparatively high capacity for their small overall comparatively high capacity for their small overall size size
convenient installation in comparison with other convenient installation in comparison with other types of pumps types of pumps
consist of a driver and a driven consist of a driver and a driven gear enclosed in a casing and in gear enclosed in a casing and in
mesh with each other mesh with each other
The gears may be of either the spur, The gears may be of either the spur, helical or spiral typehelical or spiral type
Gear pump can be classified into two Gear pump can be classified into two types:types:
(1) Internal Gear Pump(1) Internal Gear Pump
(2) External Gear Pump(2) External Gear Pump
(1) Internal Gear Pump(1) Internal Gear Pump
1. Overview1. Overview well-suited for a wide range of viscosity applications well-suited for a wide range of viscosity applications
because of their relatively low speedsbecause of their relatively low speeds superior high-viscosity handling capabilitiessuperior high-viscosity handling capabilities smooth, nonpulsating flowsmooth, nonpulsating flow self-priming and can run dryself-priming and can run dry only two moving partsonly two moving parts
22 . .How it worksHow it works
33 . .Advantages & DisadvantagesAdvantages & Disadvantages
AdvantagesAdvantages• Only two moving partsOnly two moving parts• nonpulsating discharge nonpulsating discharge • Ideal for high-viscosity Ideal for high-viscosity
liquidsliquids• Constant and even Constant and even
dischargedischarge
DisadvantagesDisadvantages • requires moderate requires moderate
speeds speeds • Medium pressure Medium pressure
limitations limitations • One bearing runs in the One bearing runs in the
product pumped product pumped • Overhung load on shaft Overhung load on shaft
bearing bearing
• Reversible pumpReversible pump• Low NPSH required Low NPSH required • Easy to maintain Easy to maintain • Flexible design offers Flexible design offers
application application customization customization
44 . .Materials of ConstructionMaterials of Construction
• Externals (head, casing, bracket)Externals (head, casing, bracket) - Cast iron, - Cast iron, ductile iron, steel, stainless steel, Alloy 20, and higher ductile iron, steel, stainless steel, Alloy 20, and higher alloys. alloys.
• Internals (rotor, idler)Internals (rotor, idler) - Cast iron, ductile iron, steel, - Cast iron, ductile iron, steel, stainless steel, Alloy 20, and higher alloys. stainless steel, Alloy 20, and higher alloys.
• BushingBushing - Carbon graphite, bronze, silicon carbide, - Carbon graphite, bronze, silicon carbide, tungsten carbide, ceramic, colomony, and other tungsten carbide, ceramic, colomony, and other specials materials as needed. specials materials as needed.
• Shaft SealShaft Seal - Lip seals, component mechanical seals, - Lip seals, component mechanical seals, industry-standard cartridge mechanical seals, gas industry-standard cartridge mechanical seals, gas barrier seals, magnetically-driven pumps. barrier seals, magnetically-driven pumps.
• PackingPacking - Impregnated packing, if seal not required. - Impregnated packing, if seal not required.
55 . .ApplicationsApplications
• Barge, tanker, and terminal loading and Barge, tanker, and terminal loading and unloading. unloading.
• Circulating. Circulating. • Transferring. Transferring. • Lubricating. Lubricating. • Booster. Booster.
• General industrial. General industrial. • Marine applications. Marine applications. • Petrochemical. Petrochemical.
((22 ) )External Gear PumpExternal Gear Pump
1. Overview1. Overview found in lubrication pumps in machine toolsfound in lubrication pumps in machine tools External gear pumps handle viscous liquidsExternal gear pumps handle viscous liquids Reduced speeds with high-viscosity liquids results in Reduced speeds with high-viscosity liquids results in
greater efficiencygreater efficiency popular for precise transfer applicationspopular for precise transfer applications
22 . .How it worksHow it works
33 . .Advantages & DisadvantagesAdvantages & Disadvantages
AdvantagesAdvantages• High speed. High speed. • Medium pressure. Medium pressure. • No overhung bearing No overhung bearing
loads. loads. • Relatively quiet Relatively quiet
operation.operation. • Design accommodates Design accommodates
wide variety of wide variety of materials.materials.
DisadvantagesDisadvantages• Four bushings in Four bushings in
liquid area. liquid area. • No solids allowed. No solids allowed. • Fixed End Clearances.Fixed End Clearances.
44 . .Materials of ConstructionMaterials of Construction
• Externals (head, casing, bracket)Externals (head, casing, bracket) - Iron, - Iron, ductile iron, steel, stainless steel. ductile iron, steel, stainless steel.
• Internals (rotor, idler)Internals (rotor, idler) - Steel, stainless steel. - Steel, stainless steel. • BushingBushing - Carbon, bronze, silicon carbide. - Carbon, bronze, silicon carbide. • Shaft SealShaft Seal - Packing, lip seal, component - Packing, lip seal, component
mechanical seal, and magnetically-driven mechanical seal, and magnetically-driven pump. pump.
55 . .ApplicationsApplications
• Industrial and mobile applications Industrial and mobile applications • Fuel and lubrication Fuel and lubrication • Metering Metering • Hydraulic applications Hydraulic applications • Precise metering applications Precise metering applications • Low-volume transfers Low-volume transfers • Light or medium duty Light or medium duty
Lobe PumpLobe Pump
1. Overview1. Overview are used in a variety of industriesare used in a variety of industries high efficiency , reliability, corrosion resistance, and high efficiency , reliability, corrosion resistance, and
good clean-in-place and service-in-place good clean-in-place and service-in-place can handle solids (e.g., cherries and olives), and a can handle solids (e.g., cherries and olives), and a
variety of liquids variety of liquids output is constant and continuous output is constant and continuous require very little maintenance require very little maintenance
22 . .How it worksHow it works
33 . .Advantages & DisadvantagesAdvantages & Disadvantages
AdvantagesAdvantages• Pass medium solids. Pass medium solids. • nonpulsating discharge nonpulsating discharge • very little maintenance very little maintenance
DisadvantagesDisadvantages• Requires timing gears. Requires timing gears. • Requires two seals. Requires two seals.
44 . .Materials of ConstructionMaterials of Construction
• Externals (head, casing, bracket)Externals (head, casing, bracket) - Cast iron - Cast iron gearbox and bracket, stainless steel gearbox, 316 gearbox and bracket, stainless steel gearbox, 316 stainless steel head and casing. stainless steel head and casing.
• Internals (rotor, idler)Internals (rotor, idler) - 316 stainless steel lobes and - 316 stainless steel lobes and shaft. shaft.
• Shaft SealShaft Seal - Lipseals, component mechanical seal, - Lipseals, component mechanical seal, double mechanical seal. double mechanical seal.
55 . .ApplicationsApplications
• Food processing. Food processing. • Dairy Produce. Dairy Produce. • Pharmaceutical. Pharmaceutical. • Biotechnology. Biotechnology. • Chemical. Chemical. • Industrial.Industrial.
Circumferential pumpCircumferential pump
External Circumferential pumpExternal Circumferential pump
How the pump worksHow the pump works
Internal Circumferential pumpInternal Circumferential pump
Screw PumpScrew Pump
1. Overview1. Overview Screw pumps are a unique type of rotary positive Screw pumps are a unique type of rotary positive
displacement pump displacement pump the flow through the pumping elements is truly axial the flow through the pumping elements is truly axial has an axial flow pattern and low internal velocities has an axial flow pattern and low internal velocities are classified as two different types: the single rotor are classified as two different types: the single rotor
and the multiple rotor and the multiple rotor
Screw pump can be classified into two Screw pump can be classified into two types:types:
(1) Single Screw Pump(1) Single Screw Pump
(2) Multiple Screw Pump(2) Multiple Screw Pump
, and Multiple Screw Pump may be Twin , and Multiple Screw Pump may be Twin Screw Pump, or Three Screw Pump.Screw Pump, or Three Screw Pump.
((11 ) )Single Screw PumpSingle Screw Pump
FeatureFeature• Applicable for all types Applicable for all types
of liquid of liquid • High reliabilityHigh reliability• Reversible Reversible • self-primingself-priming• Simple and compact Simple and compact
structure,easy structure,easy maintenancemaintenance
StructureStructure
• One rotor inside stator One rotor inside stator • Small number of parts Small number of parts • Material selection to meet various liquid Material selection to meet various liquid
((22 ) )Multiple Screw PumpMultiple Screw Pump
(2.1) Twin Screw (2.1) Twin Screw PumpPump
FeatureFeature• Applicable for all types of Applicable for all types of
liquidliquid• High reliability High reliability • self-priming self-priming
StructureStructure
• No contact between two No contact between two screws screws
• Optimal selection of Optimal selection of material to meet various material to meet various liquid liquid
((2.22.2 ) )Three Screw PumpThree Screw Pump
FeatureFeature• High reliability High reliability • Quiet operation Quiet operation • Small starting torque Small starting torque • Compact and large Compact and large
capacity capacity
StructureStructure
• Rotating elements Rotating elements consist of one power consist of one power rotor and two idler rotor and two idler rotorsrotors
• There is no direct-There is no direct-contact transmission contact transmission of power between of power between rotorsrotors
22 . .How it worksHow it works
33 . .Advantages & DisadvantagesAdvantages & Disadvantages
AdvantagesAdvantages• Wide range of liquids Wide range of liquids
and viscositiesand viscosities• Low internal velocities Low internal velocities • Low mechanical Low mechanical
vibration vibration
DisadvantagesDisadvantages• Relatively high costRelatively high cost• Performance Performance
characteristics sensitive characteristics sensitive to viscosity changeto viscosity change
• Self-priming with good Self-priming with good suction characteristics suction characteristics
• quiet operationquiet operation
• High pressure High pressure capability requires capability requires long pumping long pumping elements elements
44 . .Materials of ConstructionMaterials of Construction
• Rotating partsRotating parts: Tool Steel, Carbon Steel, Monel, etc.: Tool Steel, Carbon Steel, Monel, etc.• CasingCasing: Cast Iron, Ductile Iron, Bronze, Carbon : Cast Iron, Ductile Iron, Bronze, Carbon
Steel, Stainless Steel, Alloy Steel.Steel, Stainless Steel, Alloy Steel.
55 . .ApplicationsApplications
• Raw sewage lift stations Raw sewage lift stations • Sewage plant lift stations Sewage plant lift stations • Stormwater pumping Stormwater pumping • Land Drainage Land Drainage
Reciprocating PumpsReciprocating PumpsINTRODUCTIONINTRODUCTION
A type of positive – displacement A type of positive – displacement pumps which discharge a definite pumps which discharge a definite quantity of liquid during piston or quantity of liquid during piston or plunger movement through the plunger movement through the
stroke distancestroke distance
Basic TheoryBasic Theory
The basic principal of a reciprocating The basic principal of a reciprocating pump is that a solid will displace an pump is that a solid will displace an equal volume of fluid equal volume of fluid
This Solid may be piston or plungerThis Solid may be piston or plunger The volume of the displaced fluid is The volume of the displaced fluid is
equal to the product of the cross equal to the product of the cross sectional area of the plunger or sectional area of the plunger or piston and the height of the strokepiston and the height of the stroke
Reciprocating Pumps
Power Pumps Direct Acting Steam Pumps Diaphragm Pumps
Fixed Stroke Variable Stroke Simplex Duplex
Vertical
Horizontal
Fixed Cylinder Type
Rotary Plunger Type
Power PumpsPower Pumps
1)1) Fixed stroke power pumpsFixed stroke power pumps HorizontalHorizontal VerticalVertical
Vertical pumps are preferred when Vertical pumps are preferred when higher capacity is required and higher capacity is required and small area is presented small area is presented
HorizontalHorizontal
VerticalVertical
2) Variable Stroke2) Variable Stroke Fixed CylinderFixed Cylinder Rotary PlungerRotary Plunger
Fixed CylinderFixed Cylinder
Rotating plungerRotating plunger
Wooble plate Wooble plate
Swash PlateSwash Plate
Radial pistonRadial piston
Direct acting steam pumpDirect acting steam pump
SimplexSimplex
DuplexDuplex
Valves TypesValves Types
The valve type is determined The valve type is determined according to the pump type (Simplex according to the pump type (Simplex or Duplex)or Duplex)
Duplex valve construction is simpler Duplex valve construction is simpler than simplex valvethan simplex valve
In duplex pump the valve of one In duplex pump the valve of one cylinder takes its motion from the cylinder takes its motion from the other cylinderother cylinder
Duplex valveDuplex valve
Simplex ValveSimplex Valve
Diaphragm PumpDiaphragm Pump
Single actingSingle acting
Double actingDouble acting
Pump Maintenance. & Pump Maintenance. &
TroubleshootingTroubleshooting
TroubleshootingTroubleshooting
GeneralGeneral
Pump Problems can be either caused Pump Problems can be either caused by:by:
1. Mechanical Problem with the Pump1. Mechanical Problem with the Pumporor
2. Pump System Problem2. Pump System Problem
Before DetailsBefore Details
The Great Majority of Pump Problems are The Great Majority of Pump Problems are with the Pump Systemwith the Pump System
The Majority of Pump System Problems The Majority of Pump System Problems are on the Suction Sideare on the Suction Side
Pump Problems are usually associated Pump Problems are usually associated with Noisy Operationwith Noisy Operation
ProblemProblem
Drain it
Close both suction and discharge valves and run the pump briefly
Noise continues
Mechanical problem
Noise goes away
System Problem
Debris in the Impeller
Impeller RubbingImpeller out of
BalanceBent or Twisted shaft
Bad bearingsCoupling Misalignment
V-Belt sheave Misalignment
Pipe Stress
Cavitation Vortexing
System ProblemMechanical problem
Before beginning the Before beginning the Troubleshooting processTroubleshooting process
Be sure pressure gages are available for a pump's inlet and discharge
•Temperature gage at the pump inlet
•There should be some method of verifying pump speed through either a hand-held tachometer or strobe tachometer
•Be sure that the drivers are absolutely locked out before removing guards or conducting any system inspections
•Be certain they are fully discharged of liquid before doing any system work
INFORMATION GATHERINGINFORMATION GATHERING
Was the system undergoing routine Was the system undergoing routine maintenance? maintenance?
•Were any new or repaired components changed out?
•When was the pump last serviced? Of what did that service consist?
•What did that service consist?
•What was the appearance and condition of the pump's internal parts?
•From where were replacement parts obtained?
•For recirculating systems such as for lubrication, was new or additional liquid added?
•For one-time-through systems such as fuel oil burners, has the supplier of the fuel, fuel grade or fuel temperature changed?
•How long did the pump operate before the problem presented itself?
Positive Displacement Positive Displacement TroubleshootingTroubleshooting
RotaryRotary Reciprocating
RotaryRotary
Rotary TroubleshootingRotary Troubleshooting
SelectionSelection
When do you need to perform When do you need to perform maintenance on pumpsmaintenance on pumps??
This depends on the pump and the This depends on the pump and the application. In general, diaphragms application. In general, diaphragms on metering pumps last about on metering pumps last about 6 to 12 6 to 12 monthsmonths; gears on gear pumps last ; gears on gear pumps last about about 3 to 6 months3 to 6 months; and motors ; and motors usually last for years. usually last for years.
DC motors require periodic brush DC motors require periodic brush replacement. It is important to replacement. It is important to monitor brush wear; normally brushes monitor brush wear; normally brushes should be replaced every should be replaced every 6 months. 6 months.
RulesRules
BV Rules, Part C, Chapter 1, Section BV Rules, Part C, Chapter 1, Section 10, [6]10, [6]
I.e. Bilge Pumps
Bilge PumpsBilge Pumps Number and arrangement of pumpsNumber and arrangement of pumps
•Use of ejectors•Use of other pumps for bilge duties
•Capacity of the pumps
•Choice of the pumps •Connection of power pump
•Electrical supply of submersible pump motors .