TECHINICALSPECIFICATIONS · 2020. 7. 6. · 4 TECHINICALSPECIFICATIONS LT XLPE AB CABLE 1. SCOPE:...
Transcript of TECHINICALSPECIFICATIONS · 2020. 7. 6. · 4 TECHINICALSPECIFICATIONS LT XLPE AB CABLE 1. SCOPE:...
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TECHINICALSPECIFICATIONS
PSC Pole (9 Mtr x 300 Kg ) I. Qualification Criteria of Sub Vendor /Manufacturer:- The prospective bidder may source PSC Poles from manufacturers who should have supplied PSC Poles to Electricity Supply
Utilities / PSUs. The bidder should enclose Performance Certificates from the above users, issued in favour of the Sub Vendor / manufacturer, as proof of successful operation in field.
Applicable Standard:
The Poles shall comply with latest standards as under:
REC Specification No. 15/1979, REC Specification No. 24/1983, IS 1678, IS 2905, IS 7321.
II. Materials : Cement Cement to be used in the manufacture of pre-stressed concrete poles shall beordinary for rapid hardening Portland cement
confirming to IS: 269-1976 (Specification for ordinary and low heat Portland cement) or IS: 8041 E-1978 (Specification for rapid
hardening Portland cement). Aggregates
Aggregates to be used for the manufacture of pre-stressed concrete poles shall confirm to IS:383 (Specification for coarse and
fine aggregates from natural sources for concrete) .The nominal maximum sizes of aggregates shall in no case exceed 12mm. Water
Water should be free from chlorides, sulphates, other salts and organic matter. Potable water will be generally suitable. Admixture
Admixture should not contain Calcium Chloride or other chlorides and salts which are likely to promote corrosion of pre-stressing steel. The admixture shall conform to IS: 9103.
Pres-StressingSteel
Pre-stressing steel wires including those used as un tensioned wires should conform to IS:1785 (Part-I) (Specification for plain hard-drawn steel wire for pre-stressed concrete, Part-I cold drawn stress relieved wire).IS:1785 (Part- II)(Specification for plain hard-drawn steel wire) or IS:6003 (Specification for indented wire for pre-stressed concrete).The type design given in
theannexure are for plain wires of 4 mm diameter with a guaranteed ultimate strength of 160kg/mm².
All pre-stressing steel shall be free from splits, harmful scratches, surface flaw, rough, aged and imperfect edges and other defects likely to impair its use in pre- stressed concrete.
Concrete Mix
Concrete mix shall be designed to the requirements laid down for controlled concrete (also called design mix concrete) in IS:
1343-1980 (Code of practice for pre-stressed concrete) and IS: 456 – 1978 (Code of practice for plain and reinforced concrete) subject to the following specialconditions:
i) Minimum works cube strength at 28 days should be at least 420 Kg/cm². The concrete strength at transfer should be at least 210Kg/cm².
ii) The mix should contain at least 380 Kg of cement per cubic meter of concrete.
iii) The mix should contain as low water content as is consistent with adequate workability. It becomes necessary to add
water to increase the workability the cement content also should be raised in such a way that the original value of water cement
ratio ismaintained.
III. DesignRequirements The poles shall be designed for the following requirements:
The poles shall be planted directly in the ground with a planting depth as per IS: 1678. Wherever, planting depth is
required to be increased beyond the specified limits or alternative arrangements are required to be made on account of ground
conditions e.g. water logging etc., the same shall be in the scope of the bidder at no extra cost to owner. The bidder shall
furnish necessary design calculations/details of alternative arrangements in this regard.
The working load on the poles should correspond tothose that are likely to come on the pole during their servicelife. The factor of safety for all poles 9.0Mts. Shall not be less than 2.5 and for 8.0 M poles, the factor of safety shall not be less
than2.5.
The average permanent load shall be 40% of the working load. The F.O.S. against first load shall be 1.0.
At average permanent load, permissible tensile stress in concrete shall be 30 kg/cm².
At the design value of first crack load, the modulus of rupture shall not exceed 53.0kg/cm² for M-40. The ultimate moment capacity in the longitudinal direction should be at least one fourth of that in the transverse direction.
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The maximum compressive stress in concrete at the time oftransfer of pre- stress should not exceed 0.8 times the cube strength.
The concrete strength at transfer shall not be less than half, the 28 days strength ensured in the design, i.e. 420x0.5=210kg /cm². For model check calculations on the design of poles, referred to in the annexure, a reference may be made to the REC ―Manual
on Manufacturing of solid PCC poles, Part-I-DesignAspects‖.
IV. Dimensions andReinforcements
The cross-sectional dimensions andthe details of pre-stressing wires should conform to the particulars given in the enclosed drawing. The provisions of holes for fixing cross-arms and other fixtures should conform to the REC specificationNo.15/1979.
All pre-stressing wires and reinforcements shall be accurately fixed as shown in drawings and maintained inposition during
manufacture. The un-tensioned reinforcement as indicated in the drawings should be held in position by the use of stirrups
which should go round all thewires.
All wires shall be accurately stretched with uniform pre-stressed in each wire. Each wire or group of wires shall be anchored
positively during casing. Care should be taken to see that the anchorages do not yield before the concrete attains the
necessarystrength.
V. Cover The cover of concrete measured from the outside of pre-stressing tendon shall be normally 20mm.
VI. Welding and Lapping of Steel The high tensile steel wire shall be continuous over the entire length of the tendon. Welding shall not be allowed in any case. However, joining or coupling may be permitted provided the strengthof the joint or coupling is not less than the strength of
each individualwire. VII. Compacting
Concrete shall be compactedby spinning, vibrating, shocking or other suitable mechanical means. Hand compacting shall not bepermitted.
VIII. Curing
The concrete shall be covered with a layer of sacking, canvass, Hessian or similar absorbent material and kept constantly wet
up to the time when the strength of concrete is at least equal to the minimum strength of concrete at transfer of pre-stress.
Thereafter, the pole may be removed from the mould and watered at intervals to prevent surface cracking of the unit the interval
should depend on the atmospheric humidity and temperature. The pre-stressing wires shallbede-
tensionedonlyaftertheconcretehasattainedthespecifiedstrengthattransfer (i.e. 200 or 210 kg/cm² as applicable). The cubes cast for
the purpose of determining the strength at transfer should be coursed, a sear as possible, under condition similar to those under
which the poles are cured. The transfer stage shall be determined based on the daily tests carried out on concrete cubes till
the specified strength indicated above is reached. Thereafter the test on concrete shall be carried out asdetailed in IS: 1343(code
of practice for pre-stressed concrete). The manufacture shall supply, when required by the owner or his representative, result of
compressive test conducted in accordance with IS: 456 (Code of practice for plain and reinforced concrete) on concrete cubes
made from the concrete used for the poles. If the manufacture so desired, the manufacture shall supply cubes for test purpose
and such cubes shall be tested in accordance with IS: 456 (Code of practice for plain and reinforcedconcrete).
IX. Lifting Eye-Hooks or Holes Separate eye-hooks or hoes shall be provided for handling the transport, one each at a distance of 0.15 times the overall
length, from either end of the pole. Eye-hooks, if provided, should be properly anchored and should be on the face that has the shorter dimension of the cross-section. Holes, if provided for lifting purpose, should be perpendicular to the broad face of
thepole.
X. Holes for Cross Armsetc Sufficient number of holes shall be provided in the poles for attachment of cross arms and otherequipment.
XI. Stacking & Transportation
Stacking should be done in such a manner that the broad side of the pole is vertical. Each tier in
the stack should be supported on timber sleeper located as 0.15 times the overall length, measured from the end. The timber
supported in the stack should be aligned in verticalline.
XII. Earthing
(a) Earthing shall be provided by having length of 8 SWG GI wire embedded in Concrete during manufacture and the ends of the wires left projecting from the pole to a length of 100mm at 250 mm from top and 150 mm below groundlevel.
(b) Earth wire shall not be allowed to come in contract with the pre-stressingwires XIII. Embossing/ Engraving :During manufacturing the Pole size, Sl. No. NESCO
Utility,Manufacturer‘sname,P.ONo.&Date,MRHeadtobeEmbossed
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/ Engraved on each pole that can be clearly visible in naked eye
GUARANTEED TECHNICAL PARTICULARS OF 9MTR.300 KG PRESTRESSED
CONCRETE POLE
Sl No.
Description
Unit
Required Specification
Bidder’s
Offer
1 Name of the Manufacturer & Address
2 Type of pole Pre- Stress Concrete
3 Factor of Safety 2.5
4 Overall Length of Pole Meters Mtr. 9
5 Working Load Kg Kg 300
6 Point of application of load 600 mm below from top
7 Depth of plantation mm 1500
8 Overall Dimensions
i) Bottom Depth 355
ii) Top Depth mm 185
iii) Breadth mm 100
9 Reinforcement Detail:
i) Diameter of Pre-stressing wire mm 4
ii) No. of Tensioned wires Nos. 16
iii) No. of Un-tensioned wire Nos. --
iv) Length of each Pre-stressing wire Mtr. 9
v) Ultimate Tensile Strength Kg/cm² 17500
vi) Steel Quantity Kg/pole 14.20
10 Concrete Detail
i) Cement Type Ordinary Portland Cement
ii) Concrete mix strength Kg/cm² a) 210 Kg/cm² at time of transfer of
prestress (min)
Kg/cm² b) 420 Kg/cm² at age of 28 days (min)
iii) Concrete Quantity Cubic
meter/ pol 0.243 m³
iv) Concrete covering to wires mm 20
11 GI earthing wire size SWG/
mm 8/4.06
12 Weight of PSC Pole Kg 607
13 Standard confirming to:
Pole IS: 1678 /2000
Cement IS: 8041
Aggregates IS: 383/1970
Pre-stressing wire IS: 6003/1983
Concrete Mix IS: 456/2000
14 Tolerances Dimensions a)±15 mm on overall length of pole
b) ±5 mm on sectional dimension
c)0.5% on the uprightness of
pole
Signature of Bidder with seal
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TECHINICALSPECIFICATIONS LT XLPE AB CABLE
1. SCOPE:
This specification covers the design,manufacturing, testing,supply, deliveryandperformance requirements ofLVoverhead ISI marked 3Ph 4 wire and 1PH 2 wire XLPE insulated AerialBunchedCable(ABC)indicated in our Schedule of Requirements for use in the LVnetwork of NESCO Utility. The materials offered should have been successfully type testedatany NABLAccreditedTesting Laboratory within a period of five years on the date of bid opening. Compliance shall be demonstrated by submitting with the bid(i) authenticated copies of the type test reportsand (ii) performance certificatesfromthe users.
The Aerial Bunched Cable shall conform in all respects to highest standards of engineering, design, workmanship, this specificationand the latestrevisionsofrelevantstandardsat the time of offer and the Purchaser shall have the power to reject any work or material,which,in his judgment is not in full accordance therewith.
2. STANDARDS:
Except where modified bythis specification, the Aerial Bunched Cable shall be designed,
manufactured and testedin accordancewith thelatest editions of the followingstandards.
IES/ISO Indian Standard Material
IEC:1089 IS: 398/1994 Round wire concentriclay
Overhead electrical
Stranded Conductors.
IS: 398(Part-4)/1994 All AluminumAlloy
Conductors, Quality
ISO: 9000 Management Systems.
IS: 8130/1984 Conductors forinsulated
Electric cables.
IS: 10810/1984 Method ofTestsforcables.
IEC:502 IS:7098/1998 XLPEInsulated PVC.
Sheathed power
cables.IS:14255/1995 AerialBunched Cables for
workingvoltageup to and
including1100 volts.
The Bidder may proposealternativestandards,provide ditisdemonstratedthattheygivea degreeofquality
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andperformanceequivalenttoorbetterthanthereferencedstandards.The purchaser shalladjudgewhetherto accept or reject any standards.
TheBiddershallfurnishacopyofthealternativestandardproposedalongwithhisbid.Ifthe
alternativestandardisinalanguageotherthanEnglish,anEnglishtranslationshallbesubmitted with thestandard.
Incaseofconflicttheorderoftheprecedenceshallbe(1)IECorISOstandards,(2)Indian Standards,(3) Otheralternativestandards.This listisnottobeconsidered exhaustiveand referencetoaparticularstandard orrecommendationinthisspecificationdoesnotrelievethe
Contractororthenecessityofprovidingthegoodscomplyingwithotherrelevantstandardsor recommendation.
3.0 SERVICE CONDITIONS:
Theservice conditions shallbe as follows:
Maximum altitude abovesealevel 500m
Maximum ambient airtemperature 500C
Maximum dailyaverageambient airtemperature 350C
Maximum ambient air temperature 50C
Maximumtemperatureattainablebyan object exposedto sun 600C
Maximumyearlyweighted averageambient temperature 320C
Maximum relativehumidity 100%
Averagenumberof thunderstorm days per annum 70
Averagenumberof rainydays per annum 120
Average annualrainfall 150cm
Wind pressure as perIS:5613(Part-I/Sec.I) 1985
Wind Zones IS:5613 Part-I/Sec-I
Light Medium Heavy
Terrain Category 100Kg/m2 150Kg/m2 200Kg/m2
Environmentally,theregionwheretheworkwilltakeplaceincludescoastalareas,subjectto highrelativehumidity,whichcangiverisetocondensation.Onshorewindswillfrequentlybe salt laden.
On occasions, the combination of salt and condensation may create pollution conditions for outdoor insulators. Therefore,outdoor material shall be designed and protected for use in exposed,heavilypolluted
saltycorrosive and humid coastal atmosphere.
4. SYSTEMCONDITIONS: The materials shall be suitable for installation in supply systems of the following characteristics.
Frequency 50Hz
Nominal System Voltage 400/230V
MaximumSystem VoltageLVSystem 440/250 V
Minimum LVVoltage 370 V
Power frequencyoneminute withstand 2KV (set &dry)
Neutral EarthingarrangementLV System Solidlyearthed
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5.0 GENERAL/ TECHNICAL
ThedesignofAerialBunchedCableofferedshallcompriseacompacted,standard,harddrawn H2/
H4grade aluminum phaseconductorasapplicableunderIS-8130/84 withcrosslinked polyethylene(XLPE)insulation0.65to1.1.KVclass,havingofcarbonblackcontent2.5%± 0.5%.
Thesizes andnumberofcores requiredare: 3x50mm2 +1x35mm2(catenaries type) and 1X 35mm2
+1x25mm2
ThetypeofBunchedCablesshallbethreephaseinsulatedbundled.All Aluminum
Conductorscombinedwithaneutralandcatenaries(bare)whichshallbeofheat treated aluminum magnesium silicon alloy wires containing approximately 0.5% each of
magnesiumandsiliconrespectively.Thecatenariesmusthaveanultimatetensilestressofnot less than that specifiedinthe table oftechnical requirements.
The Bidder shall specify the standard to which this bundleshall be manufactured.
Theconductor bundle offered shall be designed to meet the requirements set out in this specification takingnoteofsafetyfactorspertainingtoconductororcatenarytensioningand NESCO specification: General Technical Requirements for LV overhead lines.
However,abidofAerialBunchedCablesshallnotbeconsidered,unlessitisaccompaniedbya list of allspecial tools andequipments necessaryto complete theinstallation.
6.0 CONDUCTORS:
The phase conductors shall be of multi-stranded aluminum of compacted circular cross section.The aluminum shall comply with IS8130:1984. The messenger conductor shall be of multi-stranded Aluminum Alloy conforming to IS398(Part4)–1994.In addition to meeting all requirement of relevant ISS the LT XLPE AB Cables supplied shall satisfy following general requirements.
(a) FOR PHASECONDUCTORS:
Sl.No. Specified Cross Section Area(mm2)
No.of strands
Min.Diaof eachstrandin
mm
Min. overall dia.
of conducting
part
Maxm. D.C Resistanceat
20degree centigrade.( Ohm/Km)
Nominal Insulation thickness
(mm)
1 35 7 2.5
4
7.62 As perISS/GTP 1.2
2 50 7 3.0
5
9.15 As perISS/GTP 1.5
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(b) FOR MESSANGER CONDUCTORS
Sl. No.
Phase conductor sizeofLT AB Cable
inmm2
Specified Cross
Section Area (mm2) of the
Messenger
conductor
No.of strands
Nominal dia.of each
strand
Min overall dia. Ofconducting
part of the compacted
conductor(mm)
Maxm. D.C Resistance
of the messenger
at20degree centigrade.( Ohm/Km)
Approx. Mass
(Kg/Km) forthe
messenger
1 25 7 2.14 6.42 As per
ISS/GTP
65
2 35 7 2.54 7.6 As per
ISS/GTP
95
6.0(b) The bidder must take required precaution to ensure that the averagediameterofeachstrandof
conductor shall be ascertained through physical measurement of dimensions of finished cables at
ambient temperature during pre-dispatch inspection or/and verification at NESCOStore by
consignee and the value so obtained shall have a tolerance limit with reference to the nominal
diameter of each strand of conductor as stated in the tables above.
7.0 TOLERANCES:
The measurement of strand diameter of the finished AB Cable shall not be less0.03mmfor
Strands upto and including 3.00mmdiameter.Forstrandsabovethatsize, measurementofstrand
diametershall not be lessthan 1%of thenominalstrand diameter.
For the purpose of checking compliance with the above requirement, the diameter shall be
determined by two measurement satright angles taken at the same cross section.The physical
measurement of strands shall be conducted after opening the strands of a finished AB Cable
offered forinspection.
8.0 SPLICESIN WIRES:
Splices in Wires shall generallycomplywith requirements ofIEC 1089. Thealuminumalloyrodsmaybesplicedbycoldpressurebutweldingbeforedrawingprovided
themanufacturercanguaranteethatthesplicecandevelop90%ofthetensilestrengthoftheun
slicedrod.Wireswhichbreakduringstrandingmaybeslicedbycoldpressurebutt-welding provided
that:
Notwosplicesinthecompletedconductoroccurwithin15mofeachotherandnotwosplicesin
anyindividual wire areless than 150m apart.
Thespliceshallbedonewithhighskilledworkmanship.Thefinishedspliceshallbesmoothand at no
point shall the cross sectional areabeless than that ofthe un sliced wire.
Splicingofthealloywiresonthestrandingmachineinordertoutilizelengthsofwiresonreels shall not
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bepermitted.
9.0 STRANDINGANDCORE LAY:
Theconductorcores shallbestranded and thedirection oflaymustbeas defined inIEC:1089.
10.0 INSULATION:
TheAerialBunchedCablesshallbeinsulatedforavoltageclassof0.65/1.1KVandshallbe capable of
operatingpermanentlyat 1.2KV.
TheinsulationwallthicknessshallbedeterminedinaccordancewithTable-4(Clause-7.2and
Clause7.3)ofIS: 14255/1995.
Theinsulatingmaterialshallbeblackandsuitabletoresistultravioletradiation,saltladen
sprays,chemicalpollution,ageingeffects,abrasionandmechanicalshocksandmechanicaland
electricalstressattemperatureup to90˚Cinnormaloperationand2500Cundershortcircuit conditions
perIEC:502/1994.
Thecarbonblackcontentin theXLPE insulation shallbe2.5%± 0.5%
11.0 PHASE IDENTIFICATION:
Theindividualinsulatedconductorswithinabundleshallbeidentifiedbymeansoflongitudinal
projections.
Thethreephaseconductorsshallbemarkedbyone,twoorthreelongitudinalprojections, indicatingthe
R,Y,Bphases respectively.
Theprojections shall havethe followingdimensions.
Thedistancebetweenthetipsoftwoadjacentprojections,wherethereismorethanone, shall
bebetween 1.0and1.5m.
Thewidth of theprojection at thebaseshall be 1.0mm; and
Theheight of the projections shall be 0.5mm.
For a single phase insulated conductor such type of phase identification shall not be required, but
embossing the NESCO on it.
12.0 INSULATION MARKINGS:
Each individual conductor comprising abundle shall have the range of non-erasable distinct
markings listed below legibly printed on the insulation surface at one meter intervals.The
embossing should be very clear&easily visible to naked eye.
ISIMark, IS14255-95, Manufacturer‟sB.I.S License No. legiblyembossed on the insulation.
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Name ofthe Purchaser.: NESCO Utility
P.O No.&Date Scheme :School &Anganwadi
Manufacturer‘strademark identification for example ―UCXLPE50‖
Year of manufacture:
Designation of conductortype
Size: for example ―3x50‖
Shapeof conductor.
Rated voltage class: 0.65/1.1KV
Backupconductoridentification:conductorswithone,twoandthreeprojectionsshallbe marked
R, Y andBrespectively. The conductor with no projection shallbemarked N and
Theheightoftheprintedletteringshallbenotlessthan20%oftheoveralldiameterof the
conductor
13.0 TWIST: Thedirectionoflayoftheconductorscomprisingthebundleshallbeleft-handedandthelay ration
shallcomplywithIEC:1089.
Withabarecatenariesconfigurationtheinsulatedphasecablestogethershallbetwistedroundtheneutralc
atenariestoformtheABC.Thiscablebundleisthen strungdirectlyontothe
distributionpolessupportedbythecatenarieswithstandardapproved hardware.
14.0 TESTS:
14.1 General
Wherenotspecified,alltestsandtestresultsshallconformtotherequirementsofIEC502/1994
orIS7098(Part-I)1998,IS10810/1984,IS: 398(Part-IV) andIS: 14255/1955.
Unlessexpresslystatedotherwise,theambienttemperatureforroutinetestsaswellasvoltage tests
shallbe20 +150Cand for allothertests be 20+150C.
Thefrequencyofthealternatingtestvoltageshallbe49Hzto51Hz.Thevoltagewaveform should
besinusoidal.
14.2 TypeTests
Thetest sample shallbe10m to 15m in length. Allcores of thebundles shallbetested. Insulation resistanceat ambient temperature.
Insulation resistanceat operatingtemperature. AC voltagetest.
Theinsulationresistancetestatambienttemperatureshallbecarriedoutinawaterbathat ambient temperature.
Theinsulationresistancetestataoperatingtemperatureshallbeconductedinawaterbathat 900C.
Thelongitudinalprojectionsusedforphaseidentificationshallbeignored.Theresultsofthistest shallbeusedtocalculatethevolumereceptivityandtheresultsconformtotherequirementsof IEC: 502/1994
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orIS10810 (Part-43).
TheACvoltagetestshallbecarriedoutbyapplying1.95KV(3U0)forfourhourstothesample, whichshallbe
submergedinawaterbathatambienttemperature,havingbeensteepedfora period not less than one hour. The
test shall only be deemed to have been passed if no breakdown occurs.
Furthermore, the followingnon-electrical typetests shallalso be carried out:
Insulationwallthickness:thelongitudinalprojectionsusedforphase1identifications shall beignored as
perIS10810 (Part-6);
Ageingtest,consistingofanevaluationoftheretentionofthemechanicalpropertiesof the insulation after
ageing.
Wrappingtest: as perIS10810 (Part-3);
Testsforbleedingand bloomingof pigment as perIS10810(Part-9)
Thermal expansion of insulation.
Measurement of carbonblack contentas perIS10810 (Part-32).
Water absorption bytheXLPE insulation, shrinkingof theXLPE insulation.
Tensiletest: adhesion between conductor and insulation.
The adhesiontestrequiresatensiletestingmachine.Asampleofatleast300mmlengthshallbe selected and straightenedout.Theinsulationshallberemovedforalengthof150mm.The insulatedendshallbeheldintheuppergripheadandthebareconductoronthelowergriphead.
Tensionshallbeapplied ataspeedof500mm/ minuntil theconductorfirstbeginstoslidewithin
theinsulation.Thetestshallhavebeenpassediftheconductorandinsulationcombinationcan stand 75N/mm2
withoutslippageoccurring. Theneutralconductor/catenariesshallbetypetestedinaccordancewiththerequirementsofIS
398(Part-IV) 1994.
14.3 RoutineTests
Thefollowingmeasurement ortests shall be carried out on all drums and coils of Bunchedcable:
Conductor resistance
Voltagetest.
Theconductortobetestedforconductorresistanceshallbestoredforatleast12hoursinaroom atparticularconstanttemperature.Ifitcannotbeestablishedthattheconductorshavereached the room temperature, the test should be postponed for a period of further 12 hours. Alternatively, the test
can be carried out on short sample after remaining one hour in a temperature controlled waterbath. Thetest shall be carried out andthe conversion factors used to
convert the resistance value to a base of 2000Cand one Km. The DCresistance of each
conductor shallnot exceed the appropriatemaximum values specifiedinIEC:228/IS:6474.
Thevoltagetestshallbeconductedbyapplyingtoeachcore3.5KVAC(2.5U0 plus2KV)or
8.4KVDCfor5minuteswiththespecimenlyinginawaterbathatambienttemperature.The conductor
shallpass thetest if no electrical breakdown occurs.
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14.4 AcceptanceTests
Thefollowingsamplecheck,measurementsandtestshallbecarriedoutinadditiontothe
AcceptanceTestsas perIS 14255– 1955,IS: 398 ( Part–IV )1994,IS8130 / 1984
Measurement of insulation wallthickness;
Measurementofdiameterofeachstrand,overalloutsidedia&CrossSectionalAreaof the conductingPart out of the finishedproduct duringpre-dispatch inspection.
Thermal expansion test; Check of physical characteristics
Tensilestrength of individual wires ofconductor.
High VoltageTest on drums immersed in water(applyvoltage3.5 KV AC for5 min)
Thesetests should be carried out on one length form each production batchofthe same sample.
Thethicknessoftheinsulationwallshallbemeasuredonapieceremovedfromeachendofthe samplelength.If eithermeansorminimumvaluesarenotmet,twofurthersamplesshallbe removedat0.5mformtheend correspondingtothefailedspecimen.Ifthesesamplesdonot
satisfythemeanandminimumthickness requirements,thetestshallbedeemedtohavebeen failed.
Thelongitudinal projections used forphaseidentifications shall be ignored. Thethermal expansion test need onlybe carried out on one core.
Inrelationtothetensiletest,thetensilestrengthofthealuminumwiresbeforestrandingandthat ofthe
finished conductorshall complywithIEC:1089.
14.5 Test on theCatenary (messenger) Conductor
Breaking load, elongation and resistance tests shall be completed on the aluminum alloy
catenaries conductor in accordancewith therequirements ofIS:398 (Part-IV)/1994 orIEC:1089.
14.6 BendingTest on a complete cable
Thistestshallbeperformedonasampleofcompletedcable.Thesampleshallbebentarounda
testmandrelatroomtemperatureforatleastonturn.Itshallthenbeunwoundandtheprocess
shallberepeatedafterturningthecablesamplearounditsaxisby1800.Thisprocessshallbe
repeatedtwicemore.Thereshallbenosignsof breakingorcrackingofthecableinsulation
duringthis test.
Thediameterof themandrel shall be:
10(D+d)
WhereD =Actual diameterof thecable (mm)
d=Actual diameter ofthe conductor(mm)
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14.7 Rejection andRetests
Shouldanyoneofthetestpiecesfirstselectedfailtopassthetests,twofurthersamplesfromthe
samebatchshallbeselectedfortesting,oneofwhichshallbefromthelengthfromwhichthe
original test sample was taken unless the length has been withdrawn bythesupplier.
Shouldthetestpiecesfrombothoftheseadditionalsamplessatisfy therequirementsofthetests,
thebatchrepresentedbythesesamplesshallbedeemedtocomplywiththestandard.Shouldthe
testpiecesfromeitherofthetwoadditionalsamplesfail,thebatchrepresentedshallbedeemed to
have failed.
15.0 COMPLIANCE WITH SPECIFICATION:
The Aerial Bunched Cable shall comply in all respects with the requirements of this
specification. However,anyminordeparturefromtheprovisionsofthespecificationshallbe
disclosed at thetime ofbiddingin theNon-complianceSchedule ofthis document.
16.0 COMPLIANCE WITH REGULATIONS:
AllthecablesshallcomplyinallrespectswiththeIndianRegulationsandActsinforce.The
cablesand connectionsshallbedesignedandarrangedtominimizetheriskoffireandany damage,
which might becausedin the event of fire.
17.0 NON-CONFORMING PRODUCT:
ThePurchaserreservestherightfordecisionsregardingacceptance,modificationorrejectionof
non-conformingitems.
18.0 INSPECTION AND TESTING:
The Purchaserorhisauthorizedrepresentativehasfreeentryatalltimes,whileworkonthe contract is being performed, to all parts of the manufacturer‘s works which concerns the processing of the cables ordered. The manufacturershall afford the purchaser or his
authorizedrepresentativeswithoutcharge,allreasonablefacilitiestoensurethatthecablebeing furnished is in accordancewith thesespecifications.
Thecablesshallsuccessfullypassalltheroutinetests&acceptanceTests referredto inthesectionontestsandthoselistedinthemostrecenteditionofthestandardsgiveninthe specification.
ThePurchaserreservestherighttorejectanyofthecablesifthetestresultsdonotcomplywith thevalues
specified or with thedategiven in the Technical data schedule.
Type Test Certificates for the tests conducted earlier shall be submitted with the bid for evaluation. Therequirements of additional typetestswillbe at thediscretion ofthe Purchaser
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ThePurchasershallwitnessroutinetests .Inordertofacilitatethis,thecontractorshall givethe purchaser
of15daysnoticethatthematerialisreadyforinspection&testing.The
suppliershallextendallassistancetotherepresentativeofthePurchaserduringhisinspection&
testingofsamplesathisworks.Thematerialsshallbedispatchedonlyafterapprovalofsuch
TestReportsandissueofDispatchclearancebythePurchaser.HoweverthePurchaserreserves
therighttoretestthematerialsafterdeliveryatanyNABL Accredited TestingLaboratoryin case
of anydisputes regarding size & quality of supplied materials at a later date during
guaranteeperiod. Thecost of such retestingshallbebornebythe supplier.
Allcostsinconnectionwiththetesting,includinganynecessaryretestingshallbebornebythe
Contractor,who shallprovidethePurchaserwithallthetestshallhavetherighttoselectthe
samplesfortestandshallalsohave therighttoensurethatthetestingapparatusiscorrect.
Measuringapparatusforroutinetestsshallbecalibratedattheexpenseofthecontractoratan approved
laboratoryandshall be approved bythepurchaser beforetesting.
TheContractorshallberesponsibleforthepropertestingofthematerialssuppliedbysub- Contractor to
thesame extent as if the materials were completed orsupplied bythe contractor.
AnycostincurredbythePurchaserinconnectionwithinspectionorretestingasaresultof failureofthe
equipmentundertestordamagedduringtransportoroffloadingshallbetothe account of theContractor.
The Third Party Independent Evaluation Agency (TPIEA) if required may be engaged by NESCO Utility
who shall have right to conduct pre & post despatch inspection jointly with NESCO Utility / independently
of the equipment / materials procured by the Purchaser.
TheContractorshallsubmittothePurchaserthreesignedcopiesofthetestCertificates,giving
theresultsofthe testsasrequired.NomaterialsshallbedispatcheduntilthePurchaserhas received the test
certificate and the contractor has been informed that theyareacceptable.
Thetestcertificatemustshowtheactualvaluesobtainedfromthetests,intheunitsusedinthis specification,
and mostmerelyconfirm that the requirements havebeen met.
Inthecaseofcomponentsforwhichspecifictypetestsorroutinetestsarenotgiveninthis specification, the
Contractor shall include a list of the tests normally required for these
components.Allmaterialsusedin theContractshallwithstandandshallbecertifiedtohave
satisfactorilypassed suchtests.
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14
NoinspectionorlackofinspectionorpassingbythePurchaser‘s representativeofequipmentor
materialswhethersupplied bytheContractororsub-Contractor,shallrelievethecontractorfrom
hisliabilitytocompletethecontractworksinaccordancewithcontractorexoneratehimfrom anyof his
guarantees.
19.0 GUARANTEE:
Thecontractor shallguaranteethe
following: Qualityand strength
ofmaterials used.
Satisfactoryoperationduringtheguaranteeperiodof 12monthsfromthedateof commissioning.
Performance figures as supplied bythe bidder in thetechnical datasheet.
20.0 PACKINGANDSHIPPING:
The cable shall be wound on strong drums or reels capable of withstanding all normal
transportation and handing.
Eachlengthofcableshallbedurablysealedbeforeshipmenttopreventingressofmoisture.The
drums reels or coils shall belagged or covered with suitablematerial to provide
physical protection for thecable duringtransitor duringstorage and handlingoperations.
Inthecaseofsteel drums adequate precautions shallbetaken to prevent damagebeing caused
by directcontactbetweenthecablesheathandthesteel.Theseprecautionshallbesubjecttothe
approval of thePurchaser.
Ifwoodendrumsareusedthenthewoodshallbetreatedtopreventdeteriorationfromattackby termites and fungi.
Each drum orreel shall carryor bemarked with followinginformation:
Individual serial number
StandardISIMark, 14255-95, Manufacturer‟sB.I.SLicenseNo.
Name ofthe Purchaser: NESCO Utility
Destination
PurchaseOrder No.&Date
Manufacturer‘sName
Yearof manufacture
Cable size and type
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15
Length of conductor(meters)
Net and Gross mass ofconductor (Kg)
Allnecessaryslingingand stackinginstructions
Destination
Countryof origin
Thedirection ofrollingas indicated byan arrow shallbemarked ona flange.
21.0 STORAGE:
The sites elected for the storage of cable drums shall be well drained and preferably have a
concrete/firmsurfacewhichwillpreventthedrumssinking into thegroundorbeing subjected to
excess waterthus causingflange rot.
Alldrumsshallstandonbattens,intheuprightpositionandinsuchamannertoallowsufficient
spacebetweenthemforadequateaircirculation.Duringstoragethedrumsshallberotated900
every threemonths.Innoinstancesshallbethedrumsbestored―flat‖ontheirflangesoroneon top
of each other.
22.0 SHIPPING:
TheContractorshallberesponsiblefortheshippingofallcables,drumsandreelssuppliedfrom
abroadtotheportsofentryandforthetransportofallgoodstovariousspecifieddestinations
includingcustoms clearance, offloading,warehousingand insurance.
TheContractorshallinformhimselffullyastoallrelevanttransportfacilitiesandrequirements
andloadinggaugesandensurethattheequipmentaspackedfortransportshallconformtothese
limitations. The contractor shallalso be responsible forverifyingthe access facilities
specified.
Thecontractorshallberesponsiblefortransportationofalltheloadsassociatedwiththecontract
andshalltakeallreasonablestepstopreventdamageofanyhighwayorbridgesbyhisvehicles
byselectingroutes,choosing propervehiclesforuseandrestrictinganddistributingloadsto
avoidtheriskofdamage.TheContractorshallimmediatelyreporttothePurchaseranyclaims
madeagainstthe contractor arising outof allegeddamageto a highwayorbridge.
All itemsofequipmentsshallbesecurelyclampedagainstmovementtoensuresafetransitfrom themanufacturer‘s facilities to thespecifieddestinations.
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16
23.0 HAZARDOUS SUBSTANCES:
TheContractor shall submit safety data sheets for all hazardous substance used with the
equipment.Thecontractorshallgiveanassurancethattherearenoothersubstancesclassifiedas
hazardousintheequipmentsupplied.Heshallalsotakeresponsibilityforthedisposalofsuch
hazardous substances that maybefound foranyinjuries resultingfrom those substances.
24.0 SUBMITTALS:
Thefollowingshallbe required in duplicate along with thebid:
Completed technical datasheets;
Descriptiveliterature givingfulltechnical detailsof equipment offered.
Outlinedimensiondrawingforeachtypeofconductor,foreachbundleshowingthe conductor
strand,composition and thebundle twist;
Typetest certificates, whereavailable, and sampleroutinetest reports;
Detailedreferencelistofcustomersalreadyusingequipmentofferedduringthelastfive years
with particular emphasison units of similar design and rating;
Performancereports from the customers forthe suppliedLT XLPE ABCables.
Detailsofmanufacturer‘squalityassurancestandardsandprogrammeandISO9000
series or equivalent national certificates;
Deviations from this specification to be submitted as per Non-Compliance. Only deviationsapproved in writingbeforeaward of contract shall beaccepted;
Listofrecommendedsparepartsforfiveyearsofoperationwithpricesandspareparts cataloguewith
pricelist for futurerequirements.
Anyotherdocumentstoestablishqualifying&credibilityrequirementsasspecifiedin this Tender
Document.
25.0 PERMANENT EMBOSSING: Allmaterialssuppliedunderthis tendershallbeardistinct markof―NESCO
Utility,andPurchaseOrderNo.&Date , Size of cable , length marking , voltage grade, Manufacturer, Trade mark , ISI mark , Phase marking, School &Anganwadi Scheme‖ bywayofembossing /enamel painting etc. includingother informationmentioned in GTP.
This should be clearlyvisibleto naked eye.
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17
GUARANTEED TECHNICAL PARTICULARSFOR 3X50+1X35 MM² and 1X35+1X25 LT
XLPE AB CABLE.
Sl
No
Description
Specified Bidder’s
Offer
1 Ref. ISS /IECfollowed IS 14255/95, IS 398 PartIV
2
PhaseConductormaterial/Insulationtype
H2 /H4 E.CgradealuminiumasperIS
8130/84 / XLPE insulation (IS
14255/95)
3 MaterialofNeutralCatenary AluminumalloyasperIS 398 Pt-IV
4 Voltage Class 0.65/1.1 KV
No. ofStrands ofPhase Conductor 7
5 No. ofstrands/Average /MinimumStrand Dia. In
mm. (Finished Phaseconductor.)
7/3.05
6
Approximate Overall Dia.Ofcompactedphase
conductor afterremovalof insulation.(in mm.)
9.15
7
No. OfStrands/Average Strand Dia.Inmm.
(NeutralCatenary.)
7/2.54
8
MinimumOverall Dia. Ofcompacted Bare Neutral
Caternary.(in mm.)
7.62
9
Minimumaverage thickness ofinsulation ofphase
Cond. (mm)
1.5
10
Minimumthickness ofinsulation ofPhase Cond.
Atany point (mm)
1.25
11 MaximumDCresistanceofPhaseconductorat20
oC
ohmn/ KM
0.64
15 MaximumDCresistanceofneutralcond. Ω/Km 0.986
16 Ultimatetensile strength ofneutralconductor(KN) 9.8
17 Maximumtemperature(Continuous) 90°Cforphaseand 75 °Cforneutral
18
Embossingon insulationateach one meterinterval
DistinctNon-erasable ISIMark, IS
14255-95, Manufacturer‟s B.I.S
LicenseNo., Name ofthe Purchaser,
Name of the manufacturer,Size
ofcable, phase marking,voltage
Gradealongwith sequentialmarkingof
length, Phase identif ication mark, ―
School &Anganwadi―
19 Cable drumlength 500 /1000m
20 Volume Resistivityofinsulation at27°C 1X1013
Ώ-cmmin.
21 Volume Resistivityofinsulation at70°C 1X1011
Ώ-cmmin.
N.B: 1)Forvaluesnot availablein relevantISS,valuesindicatedinourGTP/ TenderSpecification shallbe valid. 2)Incaseof discrepancies betweenvaluesofISS& GTP, better will prevail. 3)Averagediametersofstrandsofeachcableshallbeascertainedbyphysicalmeasurementafter openingthestrandsof eachphaseofafinishedAB Cableoffered forinspection.
Signature of the Bidder with Seal
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18
TECHNICAL SPECIFICATION OF R.S Joist Pole
1.0 Scope of Work:
This specification covers design, manufacture, testing and supply of 150x150mm RS Joist designed for a working
load of 346kg. The bidder should enclose Performance Certificates from the above users, issued in favourof the
Sub Vendor / manufacturer, as proof of successful operation infield.
Applicable Standards:
This specification covers the manufacturing, testing before dispatch and delivery of following
R.S Joists
Sl No 150x150mmRS Joist
1 150 x 150 mm R.S. Joist length:-13mtr&11mtr 34.6kg/mtr
MT
2.0 Standards:
The R.S Joists shall comply with the requirements of latest issue of IS – 2062 Gr – A except where specified
otherwise.
3.0 Climatic Conditions :
The climatic conditions at site under which the store shall operate satisfactory, are as follows Maximum
temperature of airinshade 45ºc
Maximum temperature of airinshade 0 cMaximum
temperature of airinshade 50º c Maximum rain fall per annum
2000mm Maximum temperature of air in shade 45º c
Maximum ambienttemperature
45º c Maximum humidity 100%
Av. No. of thunder storm days per annum 70%
Av. No. of dust storm per annum 20
Av. Rain fall per annum 150mm
Rolled SteelJoists
The Rolled Steel joist (RSJ) support structures shall be fabricated from mild steel, grade A and in lengths dictated
by design parameters .The joists, may include, but shall not be limited to the size i.e.150 X 150 mm;
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19
Dimensions and Properties
RSJ DES IGNATION 150 x 150 mm IS HB
Length of Joist in Mtr with +100mm/-
0% Tolerance
13mtr,11mtr,9mtr
Weight kg/m with±2.5% Tolerance 30.6
Sect ional Area (cm2) 39.00
Depth(D) o f Section (mm) with
+3.0mm/ -2.0mm Tolerance as per IS
1852-1985
150.00
Width(B)ofFlange(mm) ±4.0mm Tolerance for 150x
150 mm ISHB IS1852-1985
150.00
Thickness of Flange(Tf) (mm)
with±1.5mm Tolerance
9.00
Thickness of Web(Tw) (mm)
with±1.0mm Tolerance 8.40
Corner Radius of fillet o r root (R1) (mm) 8.00
Corner Radius of Tow (R2) (mm) 4.00
Moment o f Inertia
Ixx (cm4) Iyy (cm
4) 1540.00
460.00
Radius o f Gyration (cm)
RxxRyy 6.29
3.44
Flange Slope(α) in Degree 94.0
Tolerance in Dimension As perIS:1852
MECHANICALPROPERTIES:
Tensile Test : Requirement as perIS:2062/
1999 Grade-A
Yeild St ress(MPa) Min250
Tensile Strength(MPa) Min410
Lo=(5.65√So)Elongat ion% Min23
Bend Test Shall not Crack
CHEMICALPROPERTIES: Chemical Compos it ion Requirement as
perIS:2062/
1999 Grade-A
Permissib le variat ion over the
Specified Limit ,Percent,Max
Grade A -
Chemical Name Fe-410W A -
Carbon(%Max.) 0.23 0.02
Manganese(%Max.) 1.5 0.05
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20
Sulphur(%Max.) 0.050 0.005
Phosphorous(%Max.) 0.050 0.005
Silicon(%Max.) 0.40 0.03
Carbon Equivalent (%Max.) 0.42 -
Deoxidat ion Mode Semi-killed o r killed -
Supply condit ion As ro lled -
However,Incase ofanydiscrepancybetweentheabovedata&therelevantISS,thevalues indicatedin the IS
shallprevail.
The Acceptance Tests shall be carried out as per RelevantISS.
5.2.150x150mm RS Joists:
RS Joists of Specific Weight 34.6kg/mtrwith length 15mtr, 13mtr,11mtr & 9mtr pole of 9n0s,20nos,41nos and
11nos respectively with specif ied weight in MT shall have to be supplied as per IS:2062;2006 Grade‖A‖ ,
IS:808;1989/2001, IS1608:1995 & IS:12779-1989 and their latest amendment if any complying the
required Dimens ion, Weight, Chemical & Mechanical properties confirming to the relevant IS, as per the
Tolerance givenBelow.
APPLICABLE TOLLERANCES :
1. Length o f each po le = + 100mm / - 0 % As per relevant IS:12779-1989
(W ith p roportionate change in no o f Po les)
2. Specific Weight o f RS Jo ists = ±2.5% As per relevantIS:1852/1985
3. Weight for whole lot of supply for all categories = ±3.0% As per relevant IS: 12779-1989 for both type of RSJoists.
EMBOSSING ON EACH R.SJOIST:
Following distinct non-erasable embossing is to be made on each R.S Joists.
a) Name & Logo of theManufacturer.
b) B.I.S Logo (ISI Mark) if applicable.
c) Size of the R.SJoist
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21
GUARANTEED TECHNICAL PARTICULARS FOR
(RS JOISTS of sizes 150x150mm) (To be submitted along w ith offer)
1.1. Dimensions and Properties :
PARTICULARS S peci fication S peci fication By
the Bidder
Length o f Jo ist in Mtr with +100mm/ -0% Tolerance 13mtr &11mtr
Weight kg/m with±2.5% Tolerance 30.6
Sect ional Area (cm2) 39.00
Depth(D) o f Section (mm) with +3.0mm/ -
2.0mm Tolerance as per IS 1852-1985
150.00
Width (B)of Flange (mm) with ±2.5mm
Tolerance fo r116 x 100 mm ISMB&
±4.0mm Tolerance for 150 x 150mm
ISHB IS 1852-1985
150.00
Thickness of Flange (Tf) (mm)
with±1.5mm Tolerance
9.00
Thickness of Web(Tw) (mm) with±1.0mm
Tolerance
8.40
Corner Radius of fillet o r root (R1) (mm) 8.00
Corner Radius of Tow (R2) (mm) 4.00
Moment o f Inertia
Ixx (cm4) Iyy (cm
4)
1540.00
Radius o f Gyration(cm)
Rxx
Ryy
6.29
3.44
Modulus o f Section
Zxx(cm3) Zyy(cm
3)
205
60.2
Flange Slope(α) in Degree 94.0
Tolerance in Dimension As per IS:1852
Distinct Non -Erasab le Embossings to be
made on each R.S. Joist
a) Name & Logo of theManufacturer.
b) B.I.S Logo (ISI Mark) ifapplicable.
c) Size
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22
Signature of the bidder with Seal
11 KV “V” CROSS ARM, BACK CLAMP FOR “V”CROSS ARM
& POLETOP BRACKET (F CLAMP)
TECHNICAL SPECIFICATIONS
Qualifying Criteria:-
The prospective bidder may source the above items from manufacturers /suppliers full filling the
technical specification.
a) Hot Dip Galvanised Cross arms and Pole Top Brackets for both 33KV & 11KV construction at
intermediate and light angle pole shall be fabricated from grade 43A mild steel of channel section and
for heavy angle poles, end poles and section poles fabricated from grade 43A mild steel of angle
section. The grades of structural steel shall conform to IS – 226:1975.
b) The Back Clamp for both 33KV & 11 KV ‗V‘ cross arm shall be made out of 50 x 8 GI Flat and
shall be suitably designed to fit 150x150 mm RS Joistpole.
c) The Pole Top Bracket (F Clamp) shall be made out of 100x50 mm MS Channel (GI) for 33 KV& 75x40 MS channel (GI) suitably designed to fit 150 x150xmm RS Joistpole.
Except where otherwise indicated all dimensions are subject to the following tolerances: dimensions up
to and including 50mm:+1mm: and dimensions greater than 50mm: +2%
All steel members andother parts of fabricated material as delivered shall be free of warps, local
deformation, unauthorized splices, or unauthorized bends. Bending of flat strap shall be carried out cold. Straightening shall be carried out by pressure and not byhammering.
Straightness is of particular importance if the alignment of bolt holes along a member is
referred to its edges.
Holes and other provisions for field assembly shall be properly marked and cross referenced. Where
required, either by notations on the drawing or by the necessity of proper identification and fittings for
field assembly, the connection shall be match marked. A tolerance of not more than 1mm shall be
permitted in the distance between the center lines of boltholes.
The holes may be either drilled or punched and, unless otherwise stated, shall be not more than
2mm greater in diameter than the bolts. When assembling the components force may be used to bring the boltholestogether(providedneithermembersnorholesaretherebydistorted)butall
force must be removed before the bolt is inserted. Otherwise strain shall be deemed to be present
and the structure may be rejected even though it may be, in all other respects, in conformity with the
specification.
The back of the inner angle irons of lap joints shall be chamfered and the ends of the members cut where necessary and such other measures taken as will ensure that all members can be bolted together
without strain or distortion. In particular, steps shall be taken to relieve stress in cold worked steel so as
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23
to prevent the onset of embitterment duringgalvanizing.
Similar parts shall be interchangeable. Shapes and plates shall be fabricated and assembled in the shop to the greatest extent practicable.
Shearing flame cutting and chipping shall be done carefully, neatly and accurately. Holes shall be cut,
drilled or punched at right angles to the surface and shall not be made or enlarged by burning. Holes
shall be clean- cut without torn or ragged edges, and burrs resulting from drilling or reaming operations
shall be removed with the propertool.
Shapes and plates shall be fabricated to the tolerance that will permit field erection within tolerance,
except as otherwise specified. All fabrication shall be carried out in a neat and workmanlike manner
soas to facilitate cleaning, painting, galvanizing and inspection and to avoid areas in which water and
other matter canlodge.
Contact surfaces at all connections shall be free of loose scale, dirt, burrs, oil and other foreign materials that might prevent solid seating of the parts.
Fabrication has to be made as per drg. of„ V „ X-arm, Back clamp & „ F „clamp.
GALVANISING
All type of cross arms back clamps, F clamps & stay clamps shall be hot dip galvanized, are as
following: All galvanizing shall be carried out by the hot dip process, in accordance with Specification
IS
2629. However, high tensile steel nuts, bolts and spring washer shall be electro galvanized to Service
Condition4. The zinc coating (610 gmsper sq.mt) shall be smooth, continuous and uniform. It shall be
free from acid spot and shall not scale, blister or be removable by handling orpacking.
There shall be no impurities in the zinc or additives to the galvanic bath which could have a
detrimental effect on the durability of the zinccoating.
Before picking, all welding, drilling, cutting, grinding and other finishing operations must be completed
and all grease, paints, varnish, oil, welding slag and other foreign matter completelyremoved.
All protuberances which would affect the life of galvanizing shall also be removed.
The weight of zinc deposited shall be in accordance with that stated in Standard IS 2629 and shall
not less than 0.61kg/m² with a minimum thickness of 86 microns for items of thickness more than
5mm, 0.46kg/m² (64 microns) for items of thickness between 2mm and 5mm and 0.33kg/m²
(47 microns) for items less than 2mmthick.
Parts shall not be galvanized if their shapes are such that the pickling solutions cannot be removed with
certainty or if galvanizing would be unsatisfactory or if their mechanical strength would be reduced.
Surfaces in contact with oil shall not be galvanized unless they are subsequently coated with an oil
resistant varnish orpaint.
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24
In the event of damage to the galvanizing the method used for repair shall be subject to the a pproval of
the Engineer in Charge or that of his representative.
In no case the repair of galvanisation on site will be permitted.
The threads of all galvanized bolts and screwed rods shall be cleared of spelterby spinning or brushing.
A die shall not be used for cleaning the threads unless specifically approved by the Engineer in
Charge. All nuts shall be galvanized. The threads of nuts shall be cleaned with a tap and the
threadsoiled.
Partial immersion of the work shall not be permitted and the galvanizing tank must therefore be
sufficiently large to permit galvanizing to be carried out by one immersion.
After galvanizing no drilling or welding shall be performed on the galvanized parts of the equipment
excepting that nuts may be threaded after galvanizing. To avoid the formation of white rust galvanized
materials shall be stacked during transport and stored in such a manner as to permit adequate ventilation.
Sodium dichromate treatment shall be provided to avoid formationof white rust after hot dip
galvanization.The galvanized steel shall be subjected to test as per IS-2633.
11 KV V Cross Arm (GI): The Cross arm is to be made out of ISMC 75x40 with 50mmx6mm flat packing on top & bottom flange of the
channel where the insulator pin is to be mounted conforming to REC construction standard &drawing .
Galvanized the V cross arm as per IS-2633/1972.(Latest Amendment) , IS :2629/1985 (1st
.Revision).
Guaranteed Technical Particulars of 11KV 'V' Cross Arm
Sl. No.
Description
Specified
Bidders Offer
1 Type of Cross Arm ISMC 75x40
2 Channel Weight 7.14 Kg/mtr
3 Grade of Steel FY 250
4 Steel Standard IS:2062-1992
5 Fabrication Standard IS:802 (part - 2) - 1978
6 Dimension (75x40x4.8)mm
7 Size of M S Flat welded at both
ends 50x8mm
8 Steel Tensile Strength 1500kgf/cm²
9
Working Load
200/300/350/400Kg
10
Total Weight (with tolerance per meter + 4%)
11.2 Kg (approx.)
Signature of the bidder with Seal
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25
GUARANTEED TECHNICAL PARTICULARS FOR 11KV POLE TOP BRACKET
Sl.No. Constructional Features Spec if ied Bidders
Offer
1. Material used 65x65x6 mm MS Angle &
100x50x6 mm MS Channel
2. Overall height 380 mm
3. Flange Width (one welded & 65 mm
4. Spac ing between two flanges 100mm
5. Spacing of 2 nos of 18 mm holes for
fixing on pole top
100mm
6. C/L Distance of 2nos of 25mm
holesontopflangesofthebracket
40mm from edge
of the flange
7. Galvanization Hot dip
8. ISS 2062 ,2633
9. Draw ing enclosed
Name & Signature of
Bidder with seal
11KV POLE TOP BRACKETS (FCLAMP)
GURANTEED TECHNICAL PARTICULARS
(To be submitted along with offer)
Sl.
No.
Description Unit Unit Bidder‟s offer
11 Kv
1 Type of crossarm
2 Grade of steel
3 Steel standard
4 Fabrication Standard
5 Dimensions Mm
6 Steel section utilized
7 Steel tensile strength N/cm²
8 Working load Kg
9 Details of galvanizing method utilizedand standard/specification conforming to?
10 Weight of bracket Kg
11 Whether drawing has been submitted with the bid
Signature of the bidder with Seal
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26
BACK CLAMP FOR “V” CROSSARM
GURANTEED TECHNICAL PARTICULARS
(To be submitted along with offer)
Sl.
No.
Description Unit Unit Bidder‟s offer
11 Kv 33 Kv
1 Type of Clamp
2 Grade of steel
3 Steel standard
4 Fabrication Standard
5 Dimensions Mm
6 Steel section utilized
7 Steel tensile strength N/cm²
8 Working load Kg
9 Details of galvanizing method utilized and standard/specification conforming to?
10 Weight of back clamp Kg
11 Whether drawing has been submitted with the
bid
Signature of the bidder with Seal
Fixing of CrossArms
After the erection of supports and providing guys, the cross-arms are to be mounted on the
support with necessary clamps, bolts and nuts. The practice of fixing the cross arms before the
pole erection should be followed.
GI Clamp for HT Stay set:
HT stay clamp suitable for 150x150 mm Joist pole made out of 50x8 mm GI Flat, confirming to
latest IS Specification and .
GI Clamp for LT Stay set:
LT stay clamp suitable for PSC poles made out of 50x6 mm GI Flat, confirming to latest IS Specification.
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27
11 KV PIN INSULATOR
1. SCOPE:
The specification cover the manufacture, testing at works supply and delivery of
Porcelain insulators for overhead power lines with a nominal voltage below 12KV . Both P in
and Shackle type insulators arecovered.
2. APPLICABLESTANDARDS:
Except when they conflict with the specific requirements of this specification, the insulators
shall comply with IS : IS:731 & IS: 3188 or the latest version thereof.
3. GENERALREQUIREMENTS:
The porcelain shall be sound, free from defects, thoroughly vitrified and smoothly glazed. The
design ofthe insulators shall be such that the stresses due to expansion and contraction in any
part of the insulator shall not lead to its deterioration. The glaze shall be brown in color for
insulators. The glaze shall cover the entire porcelain surface parts except those areas that serve
as supports during firing. The insulators shall be suitable for use with all Aluminum Conductor
or Copper conductor or ACSR upto100 sq.mm. The insulators should withstand the conductor
tension the reversible wind load as well as the high frequency vibrations set due towind.
4. SYSTEM CONDITIONS:
Frequency : 50Hz
NominalSystemVoltage : 11KV
Maximum System VoltageLTSystem : 12KV Minimum LTVoltage: :11KV
Power frequency one minutewithstandVoltage(wet): 35KV
5. TYPE OFINSULATORS:
The standard Pin insulators shall be of designation Type –B of IS : 731 or its latest revision.
6. TESTS:
Typetests:
a) Visualexamination
b) Verification ofdimensions
c) Temperature cycletest
d) Dry one minute power frequency withstandtest
e) Wet one minute power frequency withstandtest
f) Mechanical strength test
g) Porositytest
Acceptancetest:
The insulators, after having withstood the routine test shall be subjected to the following
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28
acceptance tests in the order given below:
a) Verification ofDimensions.
b) Temperature cycletest
c) Mechanical strength test
d) Porositytest
Routinetests:
ii) Visual examination
7. TESTING FACILITIES:
a. The Bidder must clearly indicate what testing facilities are available in the works of the
manufacturer and whether the facilities, are adequate to carry out all the routine as well as type tests.
These facilities should be made available to Purchaser‟s Engineers if deputed to carry out or witness
the tests. If any tests cannot be carried out at the manufacturer‘s works, the reasons should be clearly
stated in thetender.
b. TheBiddershallfurnishdetailedtypetestreportsoftheoffered11KVPineinsulatorasperclauseof this specification. All the above Type Tests shall be carried out at laboratories, which are accredited, by the National Accreditation Board of Testing and Calibration Laboratories (NABL) of Government ofIndia to prove that the insulators offered meet the requirements of the specification. These Type Tests should have
been carried out within five years prior to the date of opening of thistender.
c. There offered L.T. shackle Insulators & pin insulators are already fully Type Tested at Laboratories
accredited by the National Accreditation Board of Testing and Calibration Laboratories (NABL)
withinfiveyears prior to the date of opening of the tender.There is no change in the design of Type tested
L.T. shackle Insulators andthose offers against this tender
8. Drawings :
The tender shall be accompanied with the detailed drawings showing the dimensions of the
individual insulator, giving all the design dimensions of various component parts. Generally it
shall be as perIS.
9. MARKING:
a. Each insulator shall be legibly and indelibly marked to show the following:
i) Name of Purchaser-NESCO
ii) Name or trade mark of themanufacturer
iii) Year ofmanufacturer
iv) ISI certificate, mark, ifany.
b. Marking on porcelain shall be applied beforefiring.
10. Packing:All insulators shall be packed in crates or boxes suitable for rough
handling. Packing shall be marked with the strength and voltage rating.
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29
GUARANTEEDTECHNICALPARTICULARS 11 KV PININSULATOR
Sl.
No.
Description Specific Requirement Bidders offer
Name of Manufacturer. & Address To be specified by
the bidder
Location of type testing To be specified by
the bidder
Applicable standard IS: 731,IS 3188 or
the latest version
1 Normal working voltage 11 Kv (rms)
2 High system voltage. 12 Kv (rms)
3 Visible Discharge voltage dry PF. 9 Kv (rms)
4 1 Minute withstand voltage wet PF. 65 Kv (rms)
5 1 Minute withstand voltage................. 35 Kv (rms)
6 PF puncture withstand voltage. 110 Kv (rms)
7 Impulse withstand voltage :
(+ ve) 80 Kv peak
(- ve) 80 Kv peak
8 Impulse flashover voltage :
(+ ve) 90 Kv peak
(- ve) 120 Kv peak
9 Minimum failing load. 5 KN.
10 Minimum creepage distance. 240 mm.
11 Colour of glaze. Brown.
12 Weight per unit. 1.4 Kg. (Apprx.)
13 Size of insulator. (Height) 125 mm.
(Diameter 125 mm.
14 Material of thimble. Lead.
15 Steel head. Small head.
16 Standard. IS : 731/1971.
17 Tolerance. Tolerance will be allowed as per IS :
731/1971 or latest amendments if any.
18 Drawing To be submitted
19 Conforming standard As per IS
NB- Every insulator should bear the marking of manufacturer’s name &
Purchaser’s name and ISI mark.
Name & Signature of Bidder with seal
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30
11 KV Disc insulator 45 KN (T&CType)
TECHNICAL SPECIFICATION FOR 11 KV
45 KN DISCINSULATORS
1. SCOPE:
This specification covers the manufacture, testing and works supply and delivery of 11 KV Disc insulators. The
Porcelain insulators shall conform to IS:731-1971ammended upto date. Insulators shall be of Tongue &
Clevis type (T&C).Disc insulators made of glazed porcelain shall be used as insulators on dead ends or on
suspension type lines of 11 KV and above. Tongue & Clevis type (T & C) disc insulators of mechanical strength
not less than 45KN shall be used confirming to IS: 731/1971. These shall be mounted on metallic cross-arms
with the help of suitable non-magnetic galvanised iron hardware fittings. Small f ittings like spring washers,
nuts etc may beelectro-galvanised.
2. SERVICE CONDITIONS:
The insulators to be supplied against this specification shall be suitable for satisfactory continuous operation
under the following tropical conditions.
2.1.1 Maximum ambient temperature (Degree C) … 50
2.1.2 Minimum ambient temperature (Degree C) … 3.5
2.1.3 Relative Humidity (%) … 10 to 100
2.1.4 Maximum Annual Rainfall (mm) … 1450
2.1.5. Maximum Wind pressure (kg/m.sq.) … 150
2.1.6 Maximum wind velocity (km/hour) … 45
2.1.7 Maximum altitude above mean sea level (meter) … 1000
2.1.8 Isoceraunic level (days/year) … 50
2.1.9 Seismic level (Horizontal acceleration) … 0.3 g
2.1.10 Moderately hot and humid tropical climate
conductive to rust and fungusgrowth
3. System Particulars:
a) NominalSystemVoltage 11KV
b) CorrespondinghighestsystemVoltage
c) Frequency
d) Number ofphase
e) Neutralearthing f) Min. Impulse w ithstandvoltage
12 KV
50 Hz with 3% tolerance
3
effectively grounded.
75 KV
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31
4. Standards :
Unless otherwise specified elsewhere in the specifications insulators shall confirm to the
latest revisions of all relevant standards.
5. GeneralRequirements
i) The Porcelain insulators shall generally conform to IS:731-1971 and any amendments up to date to the same.
ii) Conductors : The Disc Insulators will be used on lines on which the conductors will be A.A.A.
Conductor of size up to 100 sq. mm. The insulators should w ithstand the conductor
tension, the reversible wind load as well as the high frequency vibrations due towind.
iii) Type
a) Insulator shall be suitable for both the suspension and strain type of load & shall be of
Tongue and Clevis type. The insulators shall conform to Type ‗B‘ ofIS:731-1971.
b) Diameter of porcelain disc insulator shall be 255mm . The center to center distance between Tongue and Clevis shall be145mm.
c) InsulatorEnds.
Disc Insulators shall have Tongue and Cleave ends. The security clips will have to be
provided asperfig.25ofI.S.2486(Part-
2)1989(amendeduptodate)RECSpecif ication3/1971(Revised1993).
d) The colour of the units shall be brown for 45 KN Disc Insulators.
e) The number of units to be used both on suspension and tension strings shall be as given below:
Voltage Class Suspension
Single
Strings
Double
Tension
Single
Strings.
Double
33 3 3x2 3 3x2
22 2 2x2 2 2x2
11 1 1x2 1 1x2
iv). Electromechanical & Mechanical Strength:
The mechanical and electromechanical strength of the individual and the complete Disc shall
be 45 KN.
v) CreepageDistances :The minimum creepage distance for each 11KV disc Insulator shall 320mm.
6.0 Tests:
Suitable number of individual units and complete string shall be subject to the following tests in
accordance with IS:731/1971 with its latestamendments.
i) Type Tests :
Following Type test shall be carried out on porcelain insulators as specified in IS:
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32
731 /971 amended up to date.
1. VisualExamination.
2. Verif ication ofdimens ions. 3. Vis ible DischargeTest.
4. Impulsevoltagewithstandtest. 5. Impulsevoltageflashovertest.
6. Wet one Minute Power Frequency withstand test and West Flashovertest. 7. Temperature Cyc letest.
8. Electromechanical failing loadtest.
9. Power frequency puncture w ithstandtest. 10. Poros itytest.
11. Galvanizingtest. ii) AcceptanceTests :
The test samples after having withstood the routine test shall be subject to the
following acceptance tests in order indicated below:
1. Verif ication ofdimens ions. 2. Temperature Cyc letest.
3. Twenty four hour mechanicaltest. 4. Electromechanical failing loadtest.
5. Power Frequency puncture w ithstandtest. 6. Poros itytest.
7. Galvanizingtest.
iii) RoutineTests :
1. VisualExamination
2. Mechanicaltest
3. Electricaltest
4. Twenty four hours mechanicaltest
5. Electro mechanical failing loadtest
7 Test Certificate:
The tenderer shall furnish detailed type test reports of the offered Disc Insulators as per clause
6.1 of the Technical Specifications at the NABL approved laboratories to prove that the Disc
Insulators offered meet the requirements of the specification. These Type Tests should have
been carried out within five years prior to the date of opening of thistender.
i) Their offered Disc Insulators are already fully type tested at
approved Laboratory CPRI/NABL within five years prior to the date of
opening of this tender.
ii) There is no change in the design of type tested Disc Insulators and those offers against thistender.
iii) Such tenderers complying (i) and (ii) above shall furnish an undertaking in the
format schedule.
The purchaser reserves right to demand repetition of some or all the Type Test in
presence of purchaser‘s representative at purchaser‘s cost. For this purpose, the tenderer shall
quote unit rates for carrying out each Type Test. However, such unit rates will not be considered
for evaluation of the offer. In case the unit fails in the Type Tests, the complete supply shall
be rejected.
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33
8. Testing Facilities: The tenderer must clearly indicate what testing facilities are available in the works of the
manufacturer and whether facilities are adequate to carry out all Routine & acceptance Tests.
These facilities should be available to Board's Engineers if deputed or carry out or witness the tests
in the manufacturer works. If any test cannot becarried
outat the manufacturer's work, the reasons should be clearly stated in the tender. The insulators
shall be tested in accordance with the procedure detailed in IS-731/1971 amended up todate.
9. Material Quality and Workmanship:
The quality of porcelain and hardware in case of porcelain insulators and core & housing
in case of polymeric insulators shall be of the highest grade and best workmanship such as
is suitable and customary for extra high tens ion lines and shall conform to current IS or IEC
(only in absence of the relevantI.S.S.).
The porcelain shall be sound, free from defect, thoroughly vitr ified and smoothly glazed
and brown incolour.
Unless otherwise specified the glaze shall cover all exposed porcelain parts of the insulator.
Glazing shall be uniform and freefromdefects. Small and isolated defects in the
insulator glaze of a total surface less than 0.5 sq.cm. will however be ignored. Deviation
on this account may be supported by relevantIS.
10 Mechanical Design:
The design shall be such that stresses due to expansion and contraction in any part of insulator
shall not lead todeterioration.
Cement used in manufacture of the insulators shall not cause fracture due to expansion or
loosening due tocontraction.
11. Drawings:
The tender shall be accompanied with the detailed drawings showing the dimensions
of the individual Disc giving all the design dimens ions of various component parts. The drawing
for Insulators should clearly show the method of cementing the porcelain to the metal caps and
balls. Generally it shall be as perIS.
12. Markings:
Eachinsulatorshallbelegiblyandindeliblymarkedtoshowthefollowing: a) Name or trade mark of themanufacturer.
b) VoltageType
c) Month and year ofmanufacturing.
d) Electromechanical strength inKN
e) Property of NESCOUtility.
The―W‖clipshallbemarkedwith/punchedw iththeballandsockets izesforwhichitismeant e.g.16B,20etc. Marking on porcelain shall be printed and shall be applied beforefir ing.
13 Packing:All insulators shall be packed in crates or boxes suitable for rough handling. Packing shall be
marked with the strength and KVrating.
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34
GUARANTEED TECHNICAL PARTICULARS FOR 45 KN DISC. INSULATOR ( T&C TYPE)
Sl.
No Particulars Specific
Requirement
Bidders offer
1. Name of Manufacturer. & Address To be spec if ied by the
bidder
2. Location of type testing To be specified by
the bidder
3 Applic able standard IS-731/1971with
latestamendment
4 Type of insulator T&C type Disc insulator
5 Nominal System Voltage 11 KV
6 Highest System voltage 12 KV
7 Visible discharge Test voltage (Minimum) 9 KV
8 Dry Impulse withstand voltage +(1.2/50 microsecond wave) 75 KV
9 Dry Impulse flashover voltage+(1.2/50 microsecond wave) 90 KV
10. Dry 1 min. power frequency withstand Voltage kV. 60 KV
11 Wet 1 min. power frequency withstand Voltage . 35 KV
12 1 min. power frequency flashover Voltage kV. (Dry) 65 KV
13. 1 min. power frequency flashover Voltage kV.(Wet) 45KV
14 Power frequency puncture voltage 105 KV
15 Mechanical Routine test load 18 KN
16 Mechanical impact strength 45 KN
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35
17 Shattered strengths (Glass) .. KV
18 Electromechanical Failing Load 45 KN
19 Safe working load 18 KN
20 Minimum Failing Load 45 KN
21 Creepage Distance 320 mm
22 Type and Grade of Materials :
i) Insulators Porcelain
ii) Cap Malleable Casting or S.G
iii) Pin Forged pin
iv) Locking Split pin
v) Cement Portland
23 Type of semi conducting Glaze Ceramic
24 Colour of Insulators Dark Brown
25 Weight of single disc. kg. 4 Kg(Approx.)
26 Number of Insulators per crate 4 nos./ 6 nos.
27 Cross weight of Loaded crate 20 – 30 Kg
28 Whether drawing showing dimensional details have
been furnished along with bid.
To be enclosed by
bidder
NB : Every insulator should bear the marking of Purchaser’s name/ Manufacturer’s name
and ISI mark.
Bidders Signature with Seal
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36
11KV H.W fittings(T&CType) :
11 KV Hard Ware fittings Tongue & Clevis type ,confirming to REC Construction Standard C-2 and as per
drawing.
GUARANTEED TECHNICAL PARTICULARS FOR 11 KV H/W FITTINGS ( T&C )
Sl.No. Description Specified Bidders Offer
1. Manufacturer Name & Address
To be specified by Bidder
2. Standard Specification to which Hard ware Fittings
shallconfirm.
IS: 2486 (Part-I,II &II)
3 Ultimate strength 3000 Kg (min)
4. Dimensions in accordance with
IS: 2486(Part-II)
5 Type of washer thickness
a) Spring 2.5 mm
b)Flat 2.5 mm
6. Type of Clamp size Tension Clamp suitable for
Squiral/Weasel/ Rabbit
7. Galvanised conform to IS 2633 , IS: 4759-1996 & IS: 6747
8. Weight of Fittings ..
9. Tolerance in dimension if any
+ 5%
10. Manufacturer trade mark to be embossed on the sets
Specified by the Bidder
11. Specific drawing to be
enclosed.
Enclosed
NB. All ferrous fittings and the parts other than those of stainless steel , shall be
galvanized.
Bidder’s Signature with Seal
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37
11 KV GI Pin ) :
11 KV hot-dipped galvanizing Pin suitable for 11 KV pin insulator , confirming to REC Construction
Standard. C- 1 and confirming to IS: 2486/Part-I/1971 & Part-II/1989, IS: 1363/1984, IS: 3063/1972,
IS:2633/1972.
GUARANTEED TECHNICAL PARTICULARS FOR 11KV G.I PIN
Sl.No. Description Spec if ied Bidders Offer
1 Manufacturer Name & Address To be specified by
Bidder
2 Type of Pin 11KV
3 Applic able International Standard IS:2486 (part-II)
4 Grade Steel HDG Steel
5 Steel Spec if ication HDG Steel
6 Specification of Bolt & Nut As per ISS
7 Spec if ication of Bolt Threads As per ISS
8 Mechanical falling load (MFL) 10 KN
9 Elongation at MFL As per ISS
10 Maximum deflection of Pin Top at
MFL
1.5 mm
11 Galvanis ing Specif ication IS- 2633
12 MinimumweightofSteeldepos ited
on steelsurface
610 g/m²
13 Pin Length 315 mm
14 Shank Length 150 mm
15 StalkLength 165 mm
16 Type of Thread As per ISS
17 Thread Length As per ISS
18 Draw ing enclosed
Bidder’s Signature with Seal
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38
11 KV 200 Amp 3 Pole AB Switch
Technical Specification
01.0 Scope: -
This specification covers manufacturing testing and supply of 11KV 200 Amps 50HZ Air Break
switches for out door installation in horizontal configuration. The switches are suitable for
operation under off load conditions only and are intended for use on Distribution Sub – stations
and tapping sectionalizing points of 11 KVlines.
Description of the materials:- The 11KV A.B. Switch sets shall confirm to the following parameters: -
a. Numberofpoles 3 b. Number of Post insulatorper pole 2nos12KVpostinsulator. c. Nominalsystemvoltage 11KV
d. Highestsystemvoltage 12KV
e. Ratedfrequency 50Hz f. Systemearthling effectivelyearthed.
g. Ratednominal current 200amps h. Altitudeofinstallation Not exceeding1000M
The post insulators used in the A.B. Switches shall have the following ratings :-
a. Power frequency withstandvoltage(dry) 35KV(RMS) b. Power frequencywithstandvoltage(wet) 35KV(RMS) c. Implieswithstandvoltage(dry) 75KV
d. Power frequencypuncturewithstand 1.3
Standards:-The AB Switch Set shall conform to the following standards: -
a. IS-9920 (Part-I toV) b. IS-2544/1973 (for porcelain postinsulators) c. IS-2633, (for galvanization of ferrous parts.) or its latestamendments if any.
04.0 Insulator make: -
12KV post insulators complete with post and cap duly cemented to be used in the AB Switch
Set conforming to IS-2544/1973.
The bidder shall furnish the type test certificate of the post insulators from their manufacturer for
reference andscrutiny.
The bidder shall mention make, type of insulation materials, metal fittings, Creepage
distance, protected Creepage distance, tensile Strength, compressing strength, torsion strength and
cantileverstrength.
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39
Climatic condition:-
The A.B. Switch set shall be suitable for operation under the following climatic conditions
a. Maximumambientairtemperature 45 oC
b. Maximumdailyaverageairtemperature 35 oC
c. Maximumyearlyaverageambientairtemperature 30 oC
d. Maximum temperature attainably by abody
e. Exposed totheSum. 50 oC
f. Minimum ambientairtemperature 0 oC
g. Maximumrelativehumidity 100% h. Minimum number of rainy daysperannum 70
i. Average number of rainy daysperannum 120 j. Average annualrain fall 150cm.
k. Number of months of tropicalmonsoonconditions 4 l. Maximumwindpressure 260Kg./mm2 m. Degree of exposure toatmosphericpollution normally
n. Atmosphere. Polluted.
Other technical details: -
06.01 n General: - The 11KV A.B. Switch Set shall be the gang operated rotating single air break type having 2
post insulators per phase. The operating mechanism shall besuitable for manual operation from the
ground level and shall be so designed that all the three phases shall open or close simultaneous ly.
The Switches shall be robust in construction, easy in operation and shall be protected against over travel or
staining that might adversely affect any of its parts. The required base M.S. Channel (hot dip galvanized)
phase coupling rod, operation rod with intermediate guide braided with f lexible electrolytic copper, tail
piece of required current carrying capacity and operation mechanism with ‗ON‘ & ‗OFF‘ positions shall
be provided. The operation rod shall be medium gage of 32mm diameter nominal bore G.I. pipe single
length 6 meters. The phase coupling rod for gang operation shall be of medium gauge 25mm dia&2100
mm length nominal bore G.I. pipe. The Rating post insulators shall be provide with suitable bearing
mounted on a base channel with 8mm dia thrust collar and 6mm split pin made out of stainless steel. The
operating down rod shall be coupled to the spindle (minimum dia – 32mm) for gang operation through
another suitable bearing by two numbers 10mm dia stainless steel bolts with double nuts. All the
bearings shall be provided with grease nipple. All metal (ferrous) parts shall be galvanized an polished.
The pipe shall be galvanized in accordance with IS-4736/1968.The post insulators should be fixed with the
base channel using Galvanized Nuts andBolts.
Mounting:- The A.B. Switches shall be suitable for horizontal mounting in double pole sub-station structures. MS Galvanized base Channel &base support channel should be of min. size 75x40x6mm.
Switching Blades: - It shall be made out of electricity copper with silverplated. The approximate size shall be 220mm X 35X 6mm. The Switch shall have such a spring mechanism so as to
ensure that the speed of the opening of contact is independent of speed of manual operation.
Fixed Contacts: - The Fixed Jaw type female contacts o f s ize (70x35x6) mm shall be made of electrolytic copper (minimum 95%copper composition) duly silver coated controlled by phosphorous
bronze high pressure spring housed in robust G.I. Cover. It is essential that provision shall be made in
fixed female contracts to take the shock arising from the clos ing of move contract blade without the
same being transmitted to the post insulator. The arrangement made in this regard shall be specifically
shown in thedrawing.
Arcing Horn: - As the switches are generally meant for isolating transmission line and distribution
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40
transformers, suitable arcing horns shall be provided for breaking the charging current horn shall be
made of 8 mm dia G.I. Rod with spring assistedoperation.
Terminal Connectors: - Terminal connectors shall be robust in design. The size of fixed connector shall be
(65 X 35 X 6 mm) and size of movable connector shall be of (65 X 35) X (65 X 35) X 6mm of copper
casting with uniform machine finishing duly silver plated made out of minimum 95% copper composition
with 2nos.12mmdiaholesprovidedwithsuitablebrassboltsanddoublenuts,flatwashers&2nos.bimetallic solder less
sockets suitable up to 55 mm2 conductor.
Spacing:-Theminimumclearancebetweenphasestotheswitchshallbe
760mm. The operation down rod shall be at a transverse distance of 300mm from the outer limb of
the switch. The centre spacing between two post insulators of the same phase shall be 380 mm. In
the open position ofthe
A.B. switches the moving blade shall rotate through 90 o. This shall be exhibited in the drawing.
Sample, Drawing & Literatures: - A copy of drawings of 11KV 200Amps. A.B. Switch shall be furnished along with the tender.
The details of construction and materials of different parts of the A.B. Switch shall clearly be
indicate in the tender and illustrative pamphlet / literature for the same shall be submitted along with
thetender.
07.0 TEST & TEST CERTIFICATE:-
Type Test: - Certificate for the following type tests conducted on a prototype set of A.B. Switch in a NABL approved test house/CPRI shall have to be submitted along withoffer.
Dielectric Test (impulse and one minute were power frequency withstand voltage test.)
• Temperature rise test (for contracts andterminals)
• ShortsTimecurrentandpeakwithstandcurrenttest.
• Mainly active load breaking capacitytest.
• Transformer off-load breaking capacitytest.
• Line charging breaking capacitytest.
• Cable charging breakingtest.
• Operation and mechanical endurancetest.
• Mechanical strength test for post insulator, asper IS-2444/1937 shall be furnished.
• Testforgalvanizationofmetal(ferrous)parts.
Routine /Acceptance Test:- The inspection may be carried out by the Purchaser at any stage of manufacture. The successful
bidder shall grant free access to the Purchaser‘s representative at a reasonable time when the work is
in progress. The following routine tests shall have to be conducted on each set and results are to be
furnished for consideration of deputing inspecting officer for inspection and conduction testing of
the materials at the works of the manufacturer. the supplier shall give f ifteen days advance
intimation to the Purchaser to enable him to depute his representative for witnessing thetests.
1. Power frequency voltage drytest. 2. Measurement of resistance of maincircuit. 3. Tests to prove satisfactoryoperation. 4. DimensionCheck
5. Galvanizationtest. 6. Operationaltest. 08.00 Guaranteed Technical Particulars: -
The bidder shall furnish the guaranteed technical particular duly filled in the format along with the tender.
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41
09.0 Completeness of Equipment:-
All f ittings, accessories of apparatus which may not have been specifically mentioned in this
specification but which are usual or necessary in equipment of similar plat shall be deemed to be included
in the specification and shall be supplied by the Tender without extra charge. All plant and equipment
shall be completed in all details whether such details are mentioned in the specification ornot.
200 Am