Post on 29-Jun-2015
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It gives us immense pleasure to present
TECHNO-ECONOMIC VIABILITY OF C.I.Pipe Earthing
Vaidehi E. LinkVaidehi E. Link
OFF,-302, Shubham Appt, Landmark OFF,-302, Shubham Appt, Landmark Complex Borkute Layout Narendra Complex Borkute Layout Narendra
Nagar,Nagpur -15.Nagar,Nagpur -15.
VTC C. I.EARTH ELECTRODEVTC C. I.EARTH ELECTRODE PROPER PROPER EARTHINGEARTHING REDUCEREDUCE YOURYOUR ELECTRICITYELECTRICITY
BILLBILL
. .
• Provide an alternative path for the fault current to flow so that it will not endanger the user
• Ensure that all exposed conductive parts do not reach a dangerous potential
• Maintain the voltage at any part of an electrical system at a known value so as to prevent over current or excessive voltage on the appliances or equipment.
• Must be of low electrical resistance • Must be of good corrosion resistance • Must be able to dissipate high fault current
repeatedly
• Safety to human life & equipments)
The answer is right choice of Earthing The answer is right choice of Earthing Electrode” Electrode”
• Transmission• Telecommunication • Substations & Power
Generations• Transformer Neutral
earthing• Lightning Arrestor Earthing• Equipment Body Earthing• Data Processing Centers• Refineries & manufacturing
Facilities• Food Processing & Water
Treatment Plants• Remote & Central Office
Digital Switches• Heavy Industries• Residential Building
• Resistivity to Soil Corrosion Resistivity to Soil Corrosion • Excellent connectivity & conductivityExcellent connectivity & conductivity• Excellent & Uniform Current Excellent & Uniform Current
Dissipation Dissipation • Less capitalized cost Less capitalized cost • Pipe superiority Pipe superiority • Easy installationEasy installation• Durable & Reliable Durable & Reliable
• Reliability depends on POWERFUL METALLURGYPOWERFUL METALLURGY and the SURFACE AREASURFACE AREA of the electrode.
*In C.I. Pipe Earthing , surface area is DOUBLE
*C.I. Spun Earthing Electrode is custom casted,
capable of giving constant earth resistance
value Below 1 Ohm under normal soil
conditions for years together.• Manufactured by CENTRIFUGAL CASTING and
being a TIME TESTED Pipe ‘Durability’ of CI Pipe earthing need not be over emphasized
• The following agents tends to damage Pipe surfaces Inorganic & Organic salts, Humic acid & Fulvic acid. To circumvent these agents the presence of IRON PHOSPHIDE is there,which prevents soil corrosion. NO GALVANISATION is required to prevent from moisture
• Chemical composition (in percentage) C Mn P C.I. 3.4 0.5 0.6 • Corrosion Resistance is directly proportional to Phosphorus
content. In C.I. Pipe earthing , the presence of Phosphorous is such that Iron Phosphide is formed on the pipe surface which forms a matrix & acts as a barrier layer, preventing any further corrosion.
• It has LONGER LIFE due to large thickness & corrosion resistant properties.
• It is resistant to -Acidic water , if poured
• It is also resistant to -Residual Chlorine / Sulphate which sometimes present in soil in large quantities
The earth resistance value (ohmic value) of an earth pit The earth resistance value (ohmic value) of an earth pit depends on the physical composition of the soil, depends on the physical composition of the soil, moisture, dissolved salts, grain size and distribution, moisture, dissolved salts, grain size and distribution, seasonal variation, current magnitude etc.seasonal variation, current magnitude etc.
Resistivity of clay soil :- in the range of 4 - 150 ohm-mtr.Rocky or Gravel soil :- above 1000 ohm-mtr.
Conduction of electricity in soil is through water.
Pure water is poor conductor of electricity.About 3% salt in water drops the resistivity by 15%.
They control the manner in which the moisture is held in the soil.
• Solid connectivity upto chamber / Earth terminal
• Amenable to inspection over the life time of the electrode
• Better results in minimum earthing material in pilling process
• Copper earthing is the costliest material and reacts with soil. The best conductivity can be achieved by cast iron pipe earthing than other three types i.e. Mild Steel coated with Copper, Galvanized iron plate & Galvanized iron pipe
In C.I. pipe , excellent and uniform dissipation occurs and no maintenance is needed because of no upsurge in ‘Ohmic value’.
• Upsurge in ‘Ohmic value’ tends to drop in the entire dissipation & upset the design of system
• ‘Ohmic’ value tends to upsurge in galvanised pipes due to:-
1) Peeling off galvanisation coating during current dissipation
2) Conveying medium & acidic water attack or cement (alkaline) on G.I./ Cu pipe
3) Erosion & abrasion of the metal due to corrosion4) Thin pipe (1 to 4 mm) shall not be sustainable in
earthing system due to chemical attack in G.I./ Cu pipe
5) During high load, higher temperature at the end of G.I./Cu Pipe it expands thus prone to crack or blast.
S. N. NOMINAL DIA
[mm]
WALL THICKNESS G.I.
Dia 50mm
Wall thickness of Cast Iron compare to GI (%)
MIN. MAX. MIN. MAX.
1 80 1.5mm 3mm 7.2 (480%) 13 (433%)
2 100 7.5 (500%) 13 (433%)
3 150 8.3 (553%) 13 (433%)
Since its relative thickness is almost 5 times, the life of Cast Iron pipe electrode shall be about [1.6(pitting rate) x 5(thickness)] 8 times more, giving the lowest annual cost or capitalized cost. G.I. manufacturers expects 12 years , which shows C.I.electrode life is 96 years100 years old CI pipes in mainlines of India are still in working conditionThe higher bore of pipes reduces the power losses due to increased surface area. A very marginal higher initial cost here is to adopt minimum annual or capitalized cost. It must be interesting to note that your monthly metre reading decreases with this effective earthing due to less power lossSO LONGER LIFE & LOWER MONTHLY EXPENSES LONGER LIFE & LOWER MONTHLY EXPENSES MAKES A TECHNO-ECONOMICAL CHOICE MAKES A TECHNO-ECONOMICAL CHOICE
PIPEPIPE IS BETTER THAN PLATE The surface being circular the distance from the centre to
any point is always equal which facilitates uniform distribution of fault current from electrode to earth. Also Pipe have multistage current.
As per IS 3043:1987 (P.19 Cl.9.1.1)As per IS 3043:1987 (P.19 Cl.9.1.1)…….a “PIPE, rod or strip has a much lower resistance than a .a “PIPE, rod or strip has a much lower resistance than a
PLATE”PLATE”
CAST IRONCAST IRON IS THE BEST CHOICE
CAST IRON PIPE EARTHING IS CAST IRON PIPE EARTHING IS THE BESTTHE BEST
As per IS3043:1987 (P.47 Cl.20.5.2)Under 20.EARTHING IN As per IS3043:1987 (P.47 Cl.20.5.2)Under 20.EARTHING IN POWER STATIONS AND SUBSTATIONSPOWER STATIONS AND SUBSTATIONS
20.5.2 Choice & Design- “As an alternative to plates, cast 20.5.2 Choice & Design- “As an alternative to plates, cast iron pipes may be installed”iron pipes may be installed”
It requires less space (8” to 10” dia)& time to install the C.I.Earth set ( single component & simple mix)
1. Auguring/ Excavate2. Placing electrode with soil mix3. Fitting strip4. Test ohmic value and connect
with equipment. 5. Watering
For Sandy soil, fill soil mix with black soil & pour sufficient water to settle the soil
For Rocky soil, use two electrodes in parallel.
IMPORTANCE OF EARTHING1) SAFETY
OF
HUMAN
2) LIFE
&
EQUIPMENT
No. Description Size & Specification Qty.
INCLUDED IN KIT
1 C.I. Pipes - As Per IS: 1536 150 MM Ø x 3 Mtrs x 8.3 THK 1 No.
2 M. S. Hot Dip Galvanised Clamps 75mm x 10mm x 2 half ring 1 SET
3 Hot Dip Galvanised Nuts & Bolts M - 16 6 No.
4M. S. Plain Washer Hot Dip Galvanised
To Suit M - 16 Bolts 6 No.
5 Spring Washer Electro Galvanised To Suit M - 16 Bolts 6 No.
OPTIONAL TO CLIENT 6 Cast Iron Funnel with Wires Mesh 1 SET
7 Coke / Charcoal 100 KG
8 Common Salt 90 KG
9 Concrete Collar 1 No.
10 C. I. Cover 1 No.
11 Earthing Strip / Bus Size & Length depends on KV Installation
of Client
” C.I.PIPE Earthing Electrode GI Pipe /Pipe-n-pipe/ Copper
Plate Earthing
C.I. Pipe Earthing technology includes CUSTOM (made SPUN centrifugally) to dissipates current evenly.IRON PHOSPHIDE is there,which prevents soil corrosion. No galvanisation is required to prevent corrosion from moisture
Oxidation takes place. Resistance to dissipation starts after about 6 years.In G.I.,Galvanization eradicate with time and results in reducing the life of earthing.
Ohmic value always within safe limits.
Ohmic value fluctuates resulting in loss of costly appliances and danger to human life.
Less no. of pipes required as surface area contact is more due to bigger dia.
More no. of electrodes is required. In G.I. pipe only upto 40mm pipe is used and hence is having lesser area of contact to earth which results in poor dissipation of current
As per lab test report from HOD,Metallurgy, V.R.C.E.,Nagpur; corrosion level is very less which results in longer life
Get corroded very fast and hence the life is less
TECHNO-ECONOMICAL COMPARISIONTECHNO-ECONOMICAL COMPARISION Life Cycle analysisLife Cycle analysis
Maintenance of pit is not requirednot required in normal soil conditions.
Maintenance of earth pit requiredrequired at regular intervals.
CHOICECHOICE of using Backfill Compound or Charcoal/salt or BENTONITE as infill material; depending upon the soil condition/resistivity.
Common salt hastens corrosion of GI electrodes and the ohmic value goes high over a period of time.
Low impedanceLow impedance to activate fault relays. Due to large area and thickness of the electrode, charge dissipation through electrode is very high, current density across electrode is very low, which results in high fault current enough to trip fault relays.
Sometimes fails to activate safety devices. Distribution of short circuit current is less in terms of charge dissipation and, therefore, generates high potential at the pit resulting in low fault currentlow fault current, insufficient to trip fault protection relays
Always provides safe dischargesafe discharge path to fault current and lightning current.
Some times fails to provide safe discharge path for fault current
As pipe level is kept 4 to 6" above the earth with chamber and can be can be checkedchecked any time
As G.I. Plate is inside the earth and only G.I. strip comes out from pit; if any continuity problem comes it cancan not be checkednot be checked
Requires less space and time for installation.
Requires large space and time for installation.
No need to change. Expected life 100 years
GI Pipe earthing needs to be changed every 3 years and copper plate earthing every 12 years due to corrosion attacks.
Only one resistance for one component
Dual pipe tech. GENERATES more resistance between parts. Three parts
C.I. is used as a base of all heavy machinery and is best choice of earthing for power station as per IS 3043:1987
Not a stable platform for sensitive electronic equipment and appliances
60 models available:5 lenghts, 3 diameters, with or without clamps, with or without taper Cut. as per user requirement of LV/MV or HV/EHV , domestic or commercial ; our expertswill recommend the best option.
Limited models available :- G I Pipe Electrode Earthing: 15 - 20 micron galvanization. Size: 65NB or 38 mm x 2.75 m long
No need to put extra pipe as holes are provided from top to bottom of pipe and can be used for both purpose
Additional pipe is required for watering earth pit
Safety firstVTCELECTRODE will ensure safety to human life and appliances can
reduce risk of damage to your equipment. No compromise with
Your Costly Equipments, Cast Iron Pipe earthing (CIPE) Kit
overcomes difficult SHORT-CIRCUIT conditions!
Longest guaranteed Life
More than 40 years. 4 times to others Manufactured from custom
made C.I.Pipe, our products ensures maximum prolonged life.
Resistance to corrosion. No Maintenance cost Reliable Performance
Save Electricity wastage of improper earthing
Smooth dissipation of fault currents & lightning.
Low electrical resistance to earth.
Notes : Drawing based on IS: 3043, codes of practice for Earthing .
Easy to instalEasy to instal Control radio frequency emissions & Control radio frequency emissions & electromagnetic interferences electromagnetic interferences
Prevents damage from power surges.Prevents damage from power surges. No danger of theft like copper (being recycled)No danger of theft like copper (being recycled)
Uniform holes keep even moisture which help in Uniform holes keep even moisture which help in controlling Surge & uniform current dissipation controlling Surge & uniform current dissipation
Following parameters may be considered for the selection of Earth systems:
1) Serviceability as a cost effective system in life span
2) Evaluation of performance continuing (loss of current) diminishing current carrying capacities due to aging
3) Corrosion environment on internal (chemical constituents) & external (soil properties) surfaces
4) Study of failure-frequency of the cast iron electrode & galvanised iron electrode on year to year basis.
• DEALS IN• C I Earthing Pipe,• Bentonet Powder,• C I Chamber Cover,• G I Strip,
• The running cost per year of the total system with pipe and accessories, reliability, material assets and after wellbeing is always in center ring of customer negotiation. The Cast Iron EarthPipe economy confirms the lowest annual cost / capitalized cost.
• We have examine & establish Cast Iron Earthpipes as most “cost-effective” , “Trusted”, “Techno-economical” and “Life cordial”, equipment saver, loss saver, time saver
• In the developing country like ours, the judicious consideration of all aspects will surely advocate the use of Cast Iron Earthing Pipes only.
• FINALLY, YOU ARE THE BETTER JUDGEFINALLY, YOU ARE THE BETTER JUDGE
VTC CAST IRON EARTHING PIPES
THE RIGHT CHOICE for your need of EARTHING system
*****