Technical Specifications 11kv

Technical Specifications

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TECHNICAL

SPECIFICATIONS


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GENERAL CONSTRUCTION PRACTICES

CONSTRUCTION PRACTICES FOR 11 KV SUB-TRANSMISSION LINES 1. SURVEY AND MARKING: The preliminary survey of the line will be done jointly by CSEB and Contractors authorised representative. The survey done should be plotted on the map and submitted to CSEB Engineer-In-Charge of the work. During preliminary survey crossings/proximity to buildings and to all categories of power lines as well as telecom lines under P&T Deptt. should be clearly indicated in the route map. The detailed survey should be under taken only after the route alignment submitted is approved. The pit marking is then done at the locations. Any likely discrepancy in respect of ground/building clearance is sorted out first then the work shall be started. In case of erection to be carried out across power line, telegraph, telephone lines and public roads, the engineer in charge shall however furnish the required drawings of the crossings for the purpose. All necessary care should be taken by the contractor to avoid damage to crops and trees and properties while executing the work. 2. EXCAVATING PITS FOR ERECTION OF POLES: After the pit locations are located & peg marked on the ground, the pole pit of size 600x900x1500mm be dug. The base padding of 200mm thick with 1:3:6 cement concrete be done before erection of pole. The earthing coil should also be grounded 800mm below ground level by digging a separate pit & filling the pit with soil. The earthing coil is jointed with the earth wire provided in the base of the PCC pole and metallic fittings should be earthed with the embedded wire in the PCC pole at the top. The pole in the pole pit be erected in truly vertical position and the pit should be filled with boulders for line poles and PCC poles of DPS be concreted 0.3 Cmt. per pole. The pit is filled with 1:3:6 cement concrete mixture for size 450x600x1500mm. The poles should be erected with maximum span of 100 meters.

In case of Rail Pole/H Beam the earthing coil is bolted with the same. . The pole in the pole pit be erected in truly vertical position and the Rail Pole/H Beam and poles for DPs and tangent locations should be concreted 0.5 Cmt. per pole with 1:3:6 cement concrete mixture for size 450x600x1500mm. The poles should be erected with maximum span of 100 meters. 3. FIXING OF V CROSS ARM, TOP CLAMPS, DC CHANNELS etc. ON THE POLES: The fitting such as V cross arm, top clamps, D.C. channel etc. should be fixed on poles as per standard practice adopted in CSEB. The fabrication of above fittings should also be got done as per standard drawing available in the CSEB. The general specification of steel sections are given below:

i. V Cross arm should be made out of M.S. Angle of size 65x65x6mm. The weight of one V cross arm is approximately 10.45 Kg/Cross Arm.

ii. Top clamp should be made of M.S. Angle of size 65x65x6mm. The weight of clamp should be approximate 3.48 Kg/Top clamp.

iii. D.C. cross arm 4 centre should be made out of the M.S. channel of size 100x50x6 mm. The weight of one DC cross arm comes out 46.00 Kg D.C. and length 2370 mm.

iv. Other special fittings if required may be got fabricated as per the standard drawings of CSEB. The clamps for holdings the fittings should be fabricated out of M.S. flat 65x8 mm size as per the standard drawings of CSEB weight 3.5 Kg/Pair clamp.

All nuts & bolts used shall be of M.S. with combination of plain and spring washer and machine made.

4. FIXATION OF INSULATORS AND HARDWARE OF PINS: Insulator shall be handled carefully in all stages of loading and the individually checked for cracks, damages, loss of glaze etc. before assembling and erection of at site.

a) The 11KV galvanized steel pins made by process of forging suitable for 11KV pin insulators having maximum failing load of 5 K.N. with small steel head as per fig IB of IS 2486 (ii)/1974 shall be used. The dimension of pin shall conform to ref L-306N fig 69IS-2486 (ii)/1974. The pin shall be provided with nut (hot dip galvanized) one plain washer and one spring washer (electro galvanized).

b) The disc insulators should be fitted with 11KV Hardware for tensioning the conductor 11KV hardware should be fixed in the disc insulators as per the standard practice and in the correct position to bear the


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tension of conductor. The 11KV strain hardware fitting of aluminium alloy suitable for required size of Conductor (ACSR) should be used conforming to IS-2486 (Part-II) 1989.

The 4 feet centre DP are to be erected at the pre-decided location and six stays should be provided on

the DP. The location of pit for embedding the anchor plate and stay rod shall carefully be determined either in true alignment. The overhead line or at angle locations as per the requirement of the case. The pit 0.4x0.6x1.6 mtr. shall be excavated and anchor plate with stay rod shall be suitably aligned in such a manner that the stay wire when binded with anchor rod & stay clamp at pole, the same should make an angle of 30 degree to 45 degree from the pole in the tightened position. Cement concrete mix 1:3:6 shall be poured 0.2 cmt. in the pit, well packed with ramming adequately & cured properly. The stay clamp shall be located near and below the DC Cross arm to counter balance the tensile load of the line conductor. Stay wire shall be bound at both ends i.e. at the box and the stay rod. Fly guy/storm guy, as per the site conditions should be used after getting approval from CSEB. The stay set consisting of Anchor Rod, Anchor plate, turn buckle bow, thimble should be used at the tension locations.

The conductor shall be laid out in such a way that there is no damage to conductor. Reels of conductor should be handled carefully so that no damage to conductor strands occur. 5. STRINGING OF CONDUCTOR: Conductor should be laid out from a rotating wheel supported on jacks for easy unwinding of the conductor snatch blocks shall be used for stringing the conductor and shall have groves of a shape and size to allow early flow of conductor and ensure damage free operation. Come along clamps should be used to grip the conductor at the time of stringing. 6. SAGGING OF CONDUCTOR: All conductors sagging shall be preferred in accordance with the sag and tension tables. After the conductors have been pulled to the required sag, intermediate spans shall be checked to determine the correct sag. The conductor shall be installed on insulators secured to it by means of 6 SWG aluminium binding wire. The jumpers at the tension locations should also be bound by 6 SWG aluminium binding wire. Before fixing the conductor on insulator and strain hardware, aluminium tape should be wrapped on the conductor. 7. GUARDING: The 11KV guarding cross arm is to be fitted on the pole as per the drawing available in the CSEB for guarding the line with 8 SWG GI wire as guard wire and 10 SWG GI wire for lacing. Guarding cross arm made of 75x40x6 mm angle 5 feet long should be clamped at 300mm below the bottom arm of V cross arm. 8. ANTI-CLIMBING DEVICE: Barbed wire weighing 3.5 Kg per pole should be wrapped at a height of 3000 mm above ground level stretching in 900 mm length. Both ends of barbed should be clamped suitably to avoid coming down from its location. 9. DANGER BOARD: Danger Board for 11KV voltage and danger mark conforming to IS:2551-1963 should be fixed on each location. SPECIFICATION FOR LT LINE ON 140 Kg. 8 METER LONG PCC POLE

1. SCOPE: Planning, supply, installation, testing and commissioning of 415 Volt over-head low tension line on 140 Kg. 8 meter long PCC Pole and necessary iron fitting etc. complete. All relevant supports fittings and fixtures, conductors shall conform to their respective IS specifications. The physical layout of the work has to be got approved by the concerned competent office of CSEB before start of work. 2. POLE: The overhead LT line shall be supported on 140 Kg. 8 meter long PCC pole as specified in the schedule of item conforming to ISS. Normally one sixth of the pole length shall be buried in the ground. The supports shall suitable be spaced depending on the number and size of the conductors, number of in between plots, road crossings etc. in general, the spacing of supports shall be approximately 50-60 meters depending upon road crossing, telephone crossing etc, and in no case the inter-distance between two consecutive support shall exceed 65 meters as per rule 85 of the Indian Electricity Rules, 1956. For erection of pole, a pit size of 600x900x1500 mm should be done and base padding of 200mm thick should provided and back filling of pole pit with boulders. Suitable time of atleast seven days shall be allowed for


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setting the base concrete with proper curing etc. Then the pole shall be laid in the center of the pit and tied with ropes of adequate strength on four sides of the poles by means of suitable clamps each fixed at right angle to its other two adjacent side clamps. Loose ends of two sides of ropes forming a straight line shall be tied firmly with deep driver iron pigs located equi-distance from the corner of the pole pit. One of the two ends of remaining ropes shall be connected to turner and the opposite rope shall be kept loose and ready to be tied on deep driver iron pig when the pole attains vertical position. To avoid any chance of injury or damage to labours and technicians working at site the remaining portion of earth pit shall then be refilled with excavated soil and well consolidated. 3. CROSS ARMS AND BRACKETS: The LT cross arm shall be made up of M.S. Angle as follows:

i) LT 3 Pin Cross Arm: 50x50x6 mm size 4.5 Kg/meter, 680 mm long ii) LT 4 Pin Cross Arm: 50x50x6 mm size 4.5 Kg/meter, 980 mm long The minimum clearance between holes for U clamps shall be 300mm. A minimum space of 40mm along

the length of the bracket shall be kept spare from top hole and bottom hole of the bracket the length of cross arm and bracket shall be suitable for spacing of conductors earth wire and guarding in accordance with the minimum spacing specified in relevant ISS and in accordance to Indian Electricity Rules. The width of the bracket shall be not less than 50 Cms. 4. INSULATORS: L.T. Porcelain shackle insulators of size 90x75mm conforming to IS: 1445-1977 shall be provided and fixed in U clamps for holding the conductors. LT shackle hardware galvanizing shall conform to ISL 2633-1964 for 4 dip tests. For holding neutral conductor Aluminium bobbin insulators of size 60x50mm size with nuts bolts shall be provided. 5. CONDUCTORS: For single phase three wire line ACSR 20 Sqmm Cu.Eq. (Weasel) conductor will be used for phase and 13 Sqmm Cu.Eq. Squirrel for neutral. Similarly for three phase four wire line ACSR 20 Sqmm Cu.Eq. (Weasel) conductor will be used for phase and 13 Sqmm Cu.Eq. Squirrel for neutral. Also for three phase four wire line ACSR 30 Sqmm Cu.Eq. (Rabbitl) conductor will be used for phase and 20 Sqmm Cu.Eq Weasel for neutral in some of the locations. The conductors shall be laid out in such a manner that there is no damage to the conductors in any form. While stringing overhead conductors, there should not be any kinking. Reels of conductor should be handled carefully, so that there is no cutting, nicking or fraying of the conductor strands. Conductor should be laid out from a rotating wheel supported on jacks for easy unwinding of the conductor. The conductor shall be binded to its respective shackle insulator by means of binding wire at one of the terminal end of span. The nuts shall be unscrewed in such a manner that top of nut gets flushed with bolts surface, so as to enable the U clamp to be at maximum distance from the brackets. Aluminium sheaves fitted with ball bearing should be used at all points of conductor support for easy pulling and to ensure uniform tension throughout the conductor length. The conductor should be pulled with a proper come along clamps. Conductor shall be pulled upto a proper sag in span at or near the dead end section of the line and then binds with the shackle insulator by means of adequate size of binding wire. The tension should then be adjusted threading of nut of MS U clamp until correct sages chained in spacing near the pulling end. The conductor shall then be binded with the shackle insulators of mid span poles maintaining proper sag and tension. The overhead line shall be correctly aligned. Where there is any deviation more than 30-Degree from straight line the overhead conductor shall be shackled of at the support. Similarly terminal and function poles shall also be provided with shackle insulators. D loops shall be provided on each conductor on both sides of each LT pole and all jumpers of LT line and service line shall be done on these loops only. The size of D loop shall generally be 200mm wide, 100mm high with 150mm additional length on both sides for binding. The cross sectional area of conductor of D loop shall be the same as that of conductor to which it is being binded. Aluminium tape shall be used for each contact/jumpers on lines. Binding at all places shall be done neatly by Aluminium binding wire of size 8 SWG. 6. CLAMPS: Back clamps and stay clamps for LT line should be made up of 50x6mm MS flats. 7. GUARDING: Suitable guarding shall be provided as per provision of Rules 88 of Indian Electricity Rules. The spacing between the outermost conductor and the guard wires shall not be less than 30 Cm. both vertically and horizontally. Diamond guarding shall be provided at a distance of 4 feet min. from the pole on its each side.


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Any other type of guardings shall be done with the permission of the Engineer-In-Charge. The guard wire shall be GI and shall in no case be less than 8 SWG in size and shall have a breaking strength of not less than 635 Kg. 8. EARTHING OF PCC POLE:

i) 11KV Every pole should be earthed by earthing coil at the bottom and fittings at the top. ii) LT Every third pole should be earthed by earthing coil at the bottom and fittings at the top.

CONSTRUCTION PRACTICE OF ADDITIONAL BAY AT 33/11 KV

SUB-STATION 1. GANTRY:

a. A gantry shall mean a group of two RS joists /or H Beam of required equal sections and equal lengths joined together along their toe of both flanges, with webs of both joints facing each other, shim welded throughout the length on both sides of flange and re strengthening of joints by MS flats of 50 mm x 6 mm thick as desired and directed by Engineer-in-Charge. The RS joists shall be 175 mm x 85 mm corresponding to ISMB 175 of required length.and H Beam shall be 152x152 mm ,37.1 Kg /meter

b. Installation: The physical layout of entire sub-station with positions of equipment, bus bar structures

and outgoing feeders shall be marked at site and has to be got approved by the concerned competent officer of CSEB before start of works, support required to be erected shall be painted on 1/6th of its length with approved type of anticorrosive paint. For erection of bus bar structure supports, normally one sixth of the support shall be buried in ground. A pit of size 0.6 Mtr. x 0.9 Mtr. of required 1.5 Mtr. depth shall be excavated. A layer of 20 cm thick of 1:3:6 cement concrete poured for base pad concreting of post is to be done by 1:3:6 ratio cement concrete of size 0.45 M x 0.60 M x 1.5 M. Suitable time shall be allowed for setting the cement concrete before removal of holding ropes. Proper curing of cement concrete by means of wet gunny bag for at least seven days shall be done. All precautions shall be taken to avoid any chance of injury or damage to labors working at site.

c. Erection of structure & Equipments: After the columns/supporting structures are erected respective

equipments of 33/11 KV are to be erected carefully by suitable crane. The breaker and isolators are to be erected as 3 phase unit basis and other item like 11 KV CT, PT, LA PI etc. are to be erected on I-phase unit basis and rigidly mounted on the supporting structures.

Control relay panels are to be mounted inside the control room in the same order as in the switchyard.

After the earth mat design is finalized, the earth mat with 50x6 mm GI flat are to be put for each equipment. Then flats are to be interconnected with each other. The bus bars are to be strung after all the columns and beams are fitted. Both the bus shall be of single bus type with suitable tension insulators and 11 KV Auxiliary bus are also to be strung.

Control and power cables should be laid in consultation with Engineer-in-Charge for safe and easy maintenance. All the equipments of each 33/11 KV bays are to be connected by suitable jumpers and clamps.

d. Muffing: A layer of 1:3:6 mix cement concrete 45 cm x 45 cm on all sides of the pole upto a height of

45 cm and tapered on top shall be coasted and adequately cured for seven days. One finishing coat of cement paste shall be applied on outer surfaces of the muffing.

e. MS Iron Fittings: All channels used shall not be less than 100x50x 6 mm. All angle used shall not be

less than 65 x 65 x 8 mm corresponding to ISI 6565. MS flats used shall be of sections as directed by Engineer-in-Charge.All nut-bolts used shall be MS with a combination of plain and spring washer. Wherever required use of lock nuts shall be made without any extra cost.

2. CONDUCTORS:

Aluminum conductor steel reinforced of size 100 Sqmm having approximate ultimate tensile strength of 3299 Kg. and 0.27450 Ohm/Km resistance at 20 deg. C. conforming to IS: 398-1961 as specified in the schedule of item and directed by Engineer-in-Charge shall be used for 3 phase 3 wire 33 KV or 11 KV over head bus bars. The conductors shall be laid down in such a manner that there is no damage to


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the conductor in any form. While stringing of conductors there should not be any kinking. Conductor should be pulled upto a proper sag as directed by Engineer-in-Charge. Tension should then be adjusted until correct sag is obtained in spacing near the pulling end. Stringing chart should be used for proper stretching of conductor. The sag shall then be checked either by sighting method or by stopwatch reflected method. The conductor shall be installed on insulators secured to it by means of 6 SWG aluminium binding wire and aluminum tape on it maintaining proper tension and sag.

3. PAINTING OF POLE: - All steel poles, brackets, cross arms and all steel fittings shall be first painted with

two coat of red oxide paint. The portion of the pole to be buried inside the ground shall be painted with two coats of bitumen tar. After erection of pole, the external surface of pole and all steel items shall be painted with two coats of aluminium paint in an approved manner.

4. GUYS AND STRUTS:

a. GUYS: The guys shall consist of anchor plate, stay rod with bow and ratchet assembly, thimbles stay wires, stay grips and stay clamps. All iron fittings of stay shall be painted with Red Oxide paint. The minimum size of stay wire shall be 7/4.0 mm with and ultimate breaking strength of 6450 Kg. The stay rod shall be 20 mm dia 2 meters long fitted with bow and ratchets assembly having ultimate tensile strength of 8000 Kg. The anchor plate shall not be less than 300 x 300 x 6 mm size made up of mild steel. Turnbuckles with 20 mm dia. screw shall have ultimate breaking strength of 8000 kg.

b. CHAIN LINK FENCING: The outdoor switchyard shall be enclosed by GI wire mesh chain link fencing.

The fencing shall be supported by adequate angle iron frame work of minimum size 50 x 50 x 6 mm and shall have iron bracings of the angle iron frames. The upper parts shall be bent to the required degree and shall have four lines GI barbed wires. Framework of gates of the switchyard shall be made up of M.S. flate and (n.b) M.S. bars. The gates shall have a locking arrangement with providing 7 layers "Godrej" make lock. The gate is to be fabricated as per drawing & design provided by the Engineer-in-Charge. The minimum height of fencing post is 2.4 meters above level and 0.5 meter below ground level. The distance between angle iron supports is minimum 2.0 meter and one angle iron should be provided on top of chain link fencing around the switchyard and one angle iron (50x50x6mm) just touching the ground level around the switchyard. The complete chain link fencing work shall be painted with two coats of primer and two coats of suitable weatherproof paint.

5. CABLE AND EARTHING:

a. Cables: The cables shall be supplied, inspected, laid tested and commissioned in accordance with drawings, specifications relevant standard specifications and cable manufacturer's instructions. The MV cable shall be PVC insulated PVC sheathed alluminium conductor armoured cable of 1100 volts grade. All cable shall be inspected upon receipt at site and checked for any damage during transit by the Engineer-in-Charge before it laid down to trenches, walls etc.

b. Laying of Cables: Cables shall be laid by skilled and experienced workman using adequate rollers to

minimise stretching of the cable. Great care shall be exercised in laying cables to avoid forming kinks. The relative position of cables shall be first marked to avoid the cables crossing each other. At all points of changes in direction in horizontal as well as in and vertical planes, the cables shall be bent smooth with a radius of bend not less than 12 times the diameter of the cables. For laying cables under-ground a trench of atleast 750 mm deep of required width shall be excavated for entire length of cable route. The trench shall be brick masonry made. A bed of fine sand of 100mm thickness shall be dressed and well dressed. The cable shall be laid on the bed of sand with full precautions to avoid any kinking, twisting and damage of cable. Fine sand shall be spread over the cable and shall be flushed with top surface RCC Slab are to be placed at suitable size to cover cable trenches.

For cables to run along the wall proper and accurate verticality shall be maintained. Before

fixing the cables on walls vertical plumbed arcing shall first be made. Parallel cables shall be spaced atleast 50 mm apart maintaining their relative position over the entire length. Saddles for gripping the


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cables shall be spaced not more than 1 meter apart in order to avoid undue stress on the cables due to its own weight.

c. Earthing: All the non-current carrying metal parts of electrical installation shall be earthed

properly. All metal conduits trucking, cable sheaths, switch gear, distribution fuse boards, light fittings and all other parts made of metal shall be banded together and connected by means of specified earthing conductors to an efficient earthing system. All earthing shall be in conformity with the Indian Electricity Rules and in accordance to IS: 3043-1987.

d. Earthing Conductors: All earthing conductors shall be of GI plate, GI pipe or earthing coil of specified

size and shall be protected against mechanical injury or corrosion.

e. Sizing of Earthing Conductor: Under no circumstances the cross sectional area of earthing conductor shall be less than half of the largest current carrying conductor subject to an upper limit of 80 Sqmm. If the area of the largest current carrying conductor or bus bar exceeds 160 Sqmm. then two or more earthing conductor shall be used in parallel to provide at least half one cross sectional area of the largest current carrying conductor.

6. TYPE OF EARTH ELECTRODE:

a. Plate Electrode: Plate electrode forming a grid shall be used for earthing stations around substations. Required numbers of earth electrodes directed by Engineer-in-Charge should be provided for substation earthing. All electrodes shall be inter connected to form a grid. The substation equipments the structures shall be earthed in manner as approved and directed by Engineer-in-Charge.

b. Connections to Earth: All sub station equipment shall be earthed on a grid system. The grid around the

substation connecting earthing stations shall be of bare GI conductor of size not less than 7/3.15mm. The transformer neutral shall be connected. To the grid with two separate and independent bare GI conductor. All other sub station equipment shall be earthed with separate and independent GI strip of required section or bare GI conductor of size 6 SWG connected to grid. The earthing conductors inside the buildings shall be properly supported with clamps and brass screws. GI strips outside the building shall be laid atleast 450 mm below the finished ground level.

Over lapping in strips at joints where required shall be minimum 75 mm. The joints shall be reverted with rivets and brazed in approved manner. Sheathed lugs of adequate capacity and size shall be used for all termination of connection. Lugs shall be fitted to the equipment body to be earthed after the metal is cleaned of paint and other oily substance and properly tinned.

7. SITE TESTING AND PRE-COMMISSIONING CHECKS:

An indicative list of tests is given below. Contractor shall perform any additional test based on specialties of the items as per the Field Quality Plan / instructions of the equipments manufacturer or owner without any extra cost to the Owner. The Contractor shall arrange all instruments required for conducting these tests alongwith calibration certificates and shall furnish the list of instruments to the Owner for approval. Detailed test certificates duly signed by CSEB representative & agency representative of tests jointly carried out at site before putting the equipments in use, shall be submitted by the contractor in three copies as per following distribution:

A. o/o the Executive Engineer, B. Officer in Charge 8. GENERAL CHECKS: Check for physical damages. Visual examination of zinc coating/ painting. Check from name plate that all items are as per order/ specification. Check tightness of all bolts, clamps and connecting terminals using toque wrenches. For oil filled equipments check for oil leakage, if any. Also check oil level and top up. Check ground connections for quality of weld and application of zinc rich paint over welded joints of galvanized

surfaces. Check cleanliness of insulator and bushings.


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All checks and tests specified by the manufacturers in their drawings and manuals as well as tests specified in the relevant code of erection.

SPECIFICATION FOR 11/0.4KV 63/100 KVA TRANSFORMER DP

STRUCTURE 1. SCOPE: Design, planning, supply, installation, testing for commissioning of double pole structure (D.P. structure) for pole mounting transformer Sub-station with all allied equipments etc. complete. The Sub-station plan shall be got approved by the concerned competent office of Chief Engineer (Electrical Safety) cum Chief Electrical Advisor to Government of C.G. and concerned competent office of C.G. Electricity Board prior to erection work. 2. SUPPORTS: The D.P. structure shall have two numbers 140 Kg. 8 meter long PCC Pole for 63 & 100 KVA Sub-station as specified in the schedule of items. Normally one sixth of the pole shall be buried in the ground. The support shall be placed at a distance of 2400 mm. For erection of pole, a pit digging of size 600x900x1500 mm should be done and base padding of 200 mm thick should be provided and concreting with 0.3 Cmt per pole with 1:3:6 cement concrete mixture for size 450x600x1500 mm. Suitable time for atleast seven days shall be allowed for setting the base concrete with proper curing etc. the pole shall than be laid in the center of the pit and tied with ropes of adequate strength of four side of the pole by means of suitable clamps fixed at right angles to each other. Loose ends of two sides of ropes forming a straight line shall be tied firmly with deep driven iron pigs located equidistant from the center of the pole pit. One of the remaining two ends of remaining ropes shall be connected to turfer and the end of opposite rope shall be kept loose and ready to be tied with deep driven iron pigs shall be manned by skilled worker to control the unwanted deflection of pole while pulling it by turfer. The pole shall then be pulled by turfer and correctly aligned to its truly vertical position and then set in 1:3:6 cement concrete poured upto ground level. Suitable time shall be allowed for setting the cement concrete before removing the ropes. Proper curing of cement concrete for atleast seven days shall be done. All precautions shall be taken to avoid any chance of injury or damage to labour and technicians working at site. 3. FITTINGS: 11KV V cross arms shall be made up of MS Channel 65x65x6 mm size having phase to phase clearance of 1070 mm. 11KV top clamps shall be made up of MS angle 65x65x6 mm size 405 mm long. DC cross arms, single pole cut point DC, transformer mounting DC, AB Switch mounting DC, DO and LA mounting channel shall be made up of MS Channel 100x50x6 mm size of required length. Back clamps and stay clamps shall be made up of 65x8 mm size. MS Nut and Bolts conforming to IS: 1363-1902 shall be used of 5/8 (16mm) for fitting works and for earthing arrangements GI nut-bolts must be used. 4. AB Switch : AB switches and DO Fuses should be supplied with base steel structure, terminal bi-metallic connectors / PG clamps / earth connector. They should be checked for proper alignment and free & smooth operation. The insulators should be cleaned before commissioning. The linkage of contacts should be checked for free and adequate grip. The AB switch should be checked for fully OPEN/CLOSED positions. Contact between two movable points should be checked and recorded. The contacts should be adequately lubricated before commissioning. Connection of terminal connectors shall be checked for proper tightness. Operating handle should be separately grounded. Equipments should be supplied with detail technical specifications enclosed. The associated mounting / connection accessories items shall not be considered for measurement under any head of Price Schedule even if they happen to be appearing in Price Schedule.


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4. LIGHTENING ARRESTOR: The 11KV lightening arrestor shall be valve type arrestor consisting of an outer ceramic body containing 9 Set of resistance (Valves) and spark gaps in series. The resistance shall be made of special silicon carbide ceramic, which offer high resistance to power frequency voltages and low resistance to surge voltages. Arrestor should be installed as close as possible, to the HT line. The arrestor should be solidly earthed. The lightening arrestor shall be mounted on 100x50x6 mm MS Channel fixed approximately 1500mm below the 11KV tapping point. 5. D.O. FUSE UNIT: The 11KV drop out fuse unit shall have current carrying capacity of 200 Amps having 2 Nos 11KV post insulators fitted on bakelite base with fuse barrel as per BSS-1314. The DO fuse should be got checked and test certificate from CPRI Bangalore/Bhopal as per IS: 5792-1970 should be obtained and produced. 6. TRANSFORMERS: The 11/0.4KVstep-down distribution transformer shall be supplied and installed as per the specifications mentioned in the Transformer Section. 7. DISTRIBUTION BOX: The distribution box suitable for 63/100 KVA transformer with isolator on incoming side and SPMCCB on out going side will be used. All sheet steel work shall undergo a process of digressing, pickling in acid, cold rinsing, phosphating, possivating and then sprayed with a high corrosive resistant primer and then backed in oven. The finishing treatment shall be by application of two coats of synthetic enamel gray paint in an approved manner. 8. DANGER CAUTION BOARDS: The danger of caution boards shall have to be displayed on pole, Transformer and LT distribution panel. The danger signboards should conform to IS: 2551-1963. 9. ANTI-CLIMBING DEVICE: Anti-climbing device consisting of barbed wire extending to a minimum length of 900mm shall be provided on poles. Both ends of the barbed wire shall be secured to poles by means of suitable iron clamps as per the direction of Engineer-In-Charge. 10. PAINTING OF DP STRUCTURES: All metallic parts except transformer and LT distribution box of D.P. structure and PCC Pole shall be painted in an approved manner. 11. EARTHING OF SUB-STATION: Three numbers pipe earthing with 2.5 meter long GI Pipe 40mm dia used connecting pipe earthing with 4mm GI wire with LA transformer neutral, transformer body, DO earthing, Channel earthing. Pole pit is filled with soil.

EQUIPMENT ERECTION NOTES All support insulators; circuit breaker and other fragile equipment shall preferably be handled with cranes with suitable booms and handling capacity. The slings shall be of sufficient length to avoid any damage to insulator due to excessive swing, scratching by sling ropes etc. For cleaning the inside and outside of Hollow insulators only muslin of leather cloth shall be used. Handling equipment, sling ropes etc. Should be tested before erection and periodically for strength. Bending of compressed air piping should be done by a bending machine and through clod bending only. Bending shall be such that inner diameter of pipe is not reduced. Cutting of the pipes wherever required shall be such as-to avoid flaring of the ends, and only a proper pipe-cutting tool shall be used. Hacksaw shall be used. Hacksaw shall not be used. The Contractor shall arrange at site all the equipments, instruments and auxiliaries required for testing and commissioning of equipment.


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STORAGE OF EQUIPMENTS The Contractor shall provide and construct adequate storage shed for proper storage of equipments. Weather sensitive equipment shall be stored indoor. All equipments during storage shall be protected against damage due to acts of nature of accidents. The storage instruction of the equipment manufacturer/Owner shall be strictly adhered to. HELICALLY FORMED FITTINGS:

1 Pin insulator ties: Helically formed insulator ties shall be suitable for specified conductor size, Helically formed ties used for holding the conductor on the pin insulator shall be made of aluminum allow or aluminized steel or aluminum-clad steel wire and shall conform to the requirement of IS: 12048-1987. The ties shall be suitably for pin insulator dimensions and conductor sizes to be specified by specified by the owner. Elastomer pad for insulator shall be used with the ties to avoid abrasion of the conductor coming into direct contact with the insulator. Test : The ties shall be subjected to the tests specified in IS: 12048-1987. 2 Fittings for Strain Insulators:

The Fittings shall consist of the following components: . Cross arm strap conforming to IS:2486(Part-II)-1989. . Aluminum alloy die cast thimble-clevis for attaching to the tongue of Strain insulator on one end for accommodating the loop of the helically formed dead-end fitting at the other end in its smooth internal contour. The thimble shall be suitable for all sizes of conduct ors ranging from 7/2. 11mm to 7/3.35 mm AAAC. The thimble clevis shall be attached to the insulator by a steel cutter pin used with a non-ferrous split pin of brass or stainless steel. The thimble shall have clevis dimensions as per IS:2486(Part-II)-1989. .Helically formed dead-end grip having a prefabricated loop to fir into the grooved contour of the thimble on one end for application over the conductor at the other end. The formed fitting shall conform to the requirement of IS:12048-1987. Tests: The helically formed fittings for strain insulators shall be subjected to tests as per IS:12048-1987. The other hardware fittings shall be tested as per IS: 2486(Part-I).

The scope of work is as under:- Erection and commissioning of following :- (I) single circuit 11 KV line on PCC poles 140 Kg/8.0 meter long with maximum span 100 mtr. using Rabbit/Weasel ACSR conductor, (II) 11KV line on 60 Kg / meter 9 meter long Rail Pole or 37.1 Kg / meter 9 meter long H Beam with Rabbit conductor, (III) LT line single phase three wire & 3 phase 4 wire using weasel & squirrel ACSR conductor for phase & neutral respectively on 140 Kg. 8.0 meter long PCC pole, (IV) LT line single phase three wire & 3 phase 4 wire using Rabbit and weasel ACSR conductor for phase & neutral respectively on 140 Kg. 8.0 meter long PCC pole, (V) 11/0.4 KV pole mounted Sub-station on 140 Kg 8.0 meter long PCC pole alongwith steel structure with Transformer/without Transformer including supplying, installation & commissioning of 11 KV line/LT line and pole mounted Sub-station in the Rural area anywhere in Chhattisgarh State on turnkey basis. a) DPs on PCC poles 140 Kg/8.0 meter long shall be erected with every 1.6 Km of line in the rural area of

Chhattisgarh State. b) Survey & approach clearance.


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c) Pits digging for supports and stays & supply and erection of PCC poles /Rail Pole/ H Beam and grouting

of stays. d) i. Supply and fixing of top clamp, V Cross Arms, D.C. channels, Disc & Hardware, Pin & Pin Insulator. ii. Supply & fixing of LT 3 Pin cross arm, LT hardware nut bolt shackle insulator & earth knob. iii. Supply & fixing of LT 4 Pin cross arm, LT hardware nut bolt shackle insulator & earth knob. iv. Supply & fixing of DC cross arm, transformer mounting channel, DO and LA mounting channel, DO set, lightening arrestor, distribution box, cable & transformer. e) i. Supply and stringing of 11 KV lines with Rabbit/Weasel ACSR conductor.

ii) Supply and stringing of LT line single phase three wire using weasel (20 Sqmm Cu Eq) & Squirrel

(13 Sqmm Cu Eq) ACSR conductor for phase and neutral. iv). Supply and stringing of LT line three phase four wire using weasel (20 Sqmm Cu Eq) & Squirrel

(13 Sqmm Cu Eq) ACSR conductor for phase and neutral. v). Supply and stringing of LT line three phase four wire using Rabbit (30 Sqmm Cu Eq) & Weasel

(20 Sqmm Cu Eq) ACSR conductor for phase and neutral f) Supply and providing guarding on the line. g) i. Testing & energisation of single circuit 11 KV line.

ii. Testing & energisation of single circuit LT line. iii. Testing & energisation of pole mounted Sub-station.

h) The minimum length of 11 KV line, which will be given for execution on contract or turnkey basis shall be about 1.0 Km combine together 11KV and LT line as one job. However, if the contractor agrees, the smaller work may also be awarded. i) There are some works where PCC poles are erected. If contractors agrees, these incomplete works may also be awarded for completion of balance works.

Detailed drawing of fabricated materials may be seen at the office, if required.

SPECIFICATION FOR CONSTRUCTION OF 33 KV LINE

1. SURVEY AND MARKING: The preliminary survey of the line should be done and plotted on the map and submitted to CSEB Engineer in charge of the work. During preliminary survey crossings/proximity to buildings and to all categories of power lines as well as telecom lines under P&T Deptt. Should be clearly indicated in the route map. The detailed survey should be under taken only after the route alignment submitted is approved. The pit marking is then done at the locations. Any likely discrepancy in respect of ground/building clearance is sorted out first then the work shall be started. In case of erection to be carried out across power line, telegraph, telephone lines and public roads, the engineer in charge shall however furnish the required drawings of the crossings for the purpose. All necessary care should be taken by the contractor to avoid damage to crops and trees and properties while executing the work. 2. EXCAVATING PITS FOR ERECTION OF POLES: After the pit locations are located & peg marked on the ground, the pole pit of size 600x900x1500mm be dug. The base padding of 200mm thick with 1:3:6 cement concrete be done before erection of pole. The earthing coil should also be grounded 800mm below ground level by digging a separate pit & filling the pit with soil. The earthing coil is jointed with the earth wire provided in the base of the PCC pole and metallic fittings should be earthed with the embedded wire in the PCC pole at the top. In case of Rail Pole/H Beam the earthing coil is bolted with the same. The pole in the pole pit be erected in truly


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vertical position and the PCC pole should be filled with boulders and PCC poles of DPS be concreted 0.5 Cmt. per pole. The pit is filled with 1:3:6 cement concrete mixture for size 450x600x1500mm. The poles should be erected with maximum span of 100 meters. 3. FIXING OF V CROSS ARM, TOP CLAMPS, DC CHANNELS etc. ON THE POLES: The fitting such as V cross arm, top clamps, D.C. channel etc. should be fixed on poles as per standard practice adopted in CSEB. The fabrication of above fittings should also be got done as per standard drawing available in the CSEB. The general specification of steel sections is given below:

v. V Cross arm should be made out 9 M.S. Angle of size 75x75x6mm. The weight of one V cross arm is approximately 25.70 Kg/Cross Arm.

vi. Top clamp should be made of M.S. Angle of size 75x75x6mm. The weight of clamp should be approximate 4.08 Kg/Top clamp.

vii. D.C. cross arm 5 centre should be made out of the M.S. channel of size 100x50x6.0 mm. The weight of one DC cross arm comes out 62.3 Kg D.C. and length 3245 mm.

viii. Other special fittings if required may be got fabricated as per the standard drawings of CSEB. The clamps for holdings the fittings should be fabricated out of M.S. flat 65x8 mm size as per the standard drawings of CSEB weight 3.5 Kg/Pair clamp.

All nuts & bolts used shall be of M.S. with combination of plain and spring washer and machine made.

4. FIXATION OF INSULATORS AND HARDWARE OF PINS: Insulator shall be handled carefully in all stages of loading and the individually checked for cracks, damages, loss of glaze etc. before assembling and erection of at site.

c) The 33KV galvanized steel pins made by process of forging suitable for 33KV pin insulators having maximum failing load of 10 K.N. with small steel head as per fig IB of IS 2486 (ii)/1974 shall be used. The dimension of pin shall conform to ref L-306N fig 69IS-2486 (ii)/1974. The pin shall be provided with nut (hot dip galvanized) one plain washer and one spring washer (electro galvanized).

d) The disc insulators should be fitted with 33KV Hardware for tensioning the conductor 33KV hardware should be fixed in the disc insulators as per the standard practice and in the correct position to bear the tension of conductor. The 33KV strain hardware fitting of aluminium alloy suitable for Dog Conductor (ACSR) should be used conforming to IS-2486 (Part-II) 1989.

The 5 feet centre DP are to be erected at the pre-decided location and six stays should be provided on

the DP. The location of pit for embedding the anchor plate and stay rod shall carefully be determined either in true alignment. The overhead line or at angle locations as per the requirement of the case. The pit 0.4x0.6x1.6 mtr. shall be excavated and anchor plate with stay rod shall be suitably aligned in such a manner that the stay wire when binded with anchor rod & stay clamp at pole, the same should make an angle of 30 degree to 45 degree from the pole in the tightened position. Cement concrete mix 1:3:6 shall be poured 0.3 cmt. in the pit, well packed with ramming adequately & cured properly. The stay clamp shall be located near and below the DC Cross arm to counter balance the tensile load of the line conductor. Stay wire shall be bound at both ends i.e. at the box and the stay rod. Fly guy/storm guy, as per the site conditions should be used after getting approval from CSEB. The stay set consisting of Anchor Rod, Anchor plate, turn buckle bow, thimble should be used at the tension locations.

The conductor shall be laid out in such a way that there is no damage to conductor. Reels of conductor

should be handled carefully so that no damage to conductor strands occur. 5. STRINGING OF CONDUCTOR: Conductor should be laid out from a rotating wheel supported on jacks for easy unwinding of the conductor snatch blocks shall be used for stringing the conductor and shall have groves of a shape and size to allow early flow of conductor and ensure damage free operation. Come along clamps should be used to grip the conductor at the time of stringing. 6. SAGGING OF CONDUCTOR: All conductors sagging shall be preferred in accordance with the sag and tension tables. After the conductors have been pulled to the required sag, intermediate spans shall be checked to determine the correct sag. The conductor shall be installed on insulators secured to it by means of 6 SWG aluminium binding wire. The jumpers at the tension locations should also be bound by 6 SWG aluminium binding wire. Before fixing the conductor on insulator and strain hardware, aluminium tape should be wrapped on the conductor.


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7. GUARDING: The 33KV guarding cross arm is to be fitted on the pole as per the drawing available in the CSEB for guarding the line with 6 SWG GI wire as guard wire and 8 SWG GI wire for lacing. Guarding cross arm made of 75x75x6 mm angle 8 feet long should be clamped at 300mm below the bottom arm of V cross arm. 8. ANTI-CLIMBING DEVICE: Barbed wire weighing 35 Kg per pole should be wrapped at a height of 3000 mm above ground level stretching in 900 mm length. Both ends of barbed should be clamped suitably to avoid coming down from its location. 9. DANGER BOARD: Danger Board for 33KV voltage and danger mark conforming to IS: 2551-1963 should be fixed on each location.

IMPORTANT INSTRUCTIONS BEFORE FILLING UP THE PRICE BID

Rates entered against each items shall deemed to have included the following works:

1. All nuts, bolts and screw etc. of required size. Measurement and payment of nut bolts screw etc.

shall not be made with the items of iron/steel hardware. Nuts and bolts should be machine made only of renamed makes.

2. All mechanical works e.g. fabrication, cutting, drilling, welding, grinding, painting and blacksmith works etc.

3. Cable and overhead conductors terminations, crimping of lugs with crimping tools and cost of appropriate size of lugs, cable glands etc.

4. Providing and applying sealing compounds, insulating toughness compound wherever required and directed.

5. Touching up all damaged paint with one coat of red oxide primer and two finishing coats of approved synthetic enamel paint.

6. All fixing accessories such as saddles, brass screws, lug plugs etc. 7. Cutting chases, holes and making good the same wherever required. 8. All lead and lift, transportation of materials at site, loading unloading and all labour required

completing the job. 9. The items are complete in itself and any allied work or equipments not mentioned in the

nomenclature of item but forming part of the system shall in all respect deemed to be included within the meaning of the execution of the said item and shall not be paid extra than the tendered rates until and unless specified. The tenderer are therefore advised to have clear under-standing of the 33 KV sub station and 33 & 11 KV & LT KV line work before filling in the rates.

10. Each and every item shall be reading continuation with its respective specification for work and specific requirements of relevant Indian Standard Specification and local Electricity Authority before filling up the rates.

11. Drilling and cutting holes in brick/RCC walls for clamping cables, earth leads, earth strips, GI pipes or whatever it may be including cost of clamping device.


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Technical

Specification

of Items

TECHNICAL SPECIFICATION OF 11 & 33 KV PIN INSULATOR


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1. SCOPE:- This specification covers the design, manufacture, testing, supply and delivery of 11 KV and 33 KV Porcelain Pin Insulators for use on 11 KV and 33 KV overhead Power Lines. 2. STANDAND:- Except where they conflict with specific requirement in the specification, the Pin Insulators shall comply with the Indian Standard Specification IS:731-1971 and its amendments from time to time. The insulator conforming to any other internationally accepted standard which ensures equal or better quality than the standard mentioned above would also be acceptable. Where the material is offered according to the international standards, an English version of the specifications shall be attached with the tender. 3. ATMOSPHERIC CONDITIONS:- 3.1 The material offered shall be suitable for operation under the climatic conditions indicated in Clause 31 of Annexure II General Terms and Conditions of purchase appended with this Tender Specification. 3.2 Reference atmospheric conditions at which insulators characteristics shall be expressed for the purpose of comparison shall:- Ambient Temperature -20 Degree Centigrade Barometric Pressure - 1013 Milli bars Absolute Humidity -11 gms of water per cubic meter corresponding to 63 percent

relative humidity at 20 Degree Centrigrade Note:- A pressure of 1013 millibars is equivalent to a pressure of 750 mm of Mercury at 0 degree centigrade. 3.3 Tests for the purpose of this standard shall preferably be carried out under conditions of temperature and humidity specified in IS:196-1966(i.e. at a temperature of 27+ 2 degree centigrade and relative humidity of 66+2 percent) and at the prevailing atmospheric pressure. When this is not possible, test may be carried out under conditions naturally obtained at the time of the test. The barometric pressure, air temperature and humidity shall be recorded for the purpose of correction. Corrections of test voltage for atmospheric conditions is given in Appendix A of IS:731-1971. 4. The Thimble for 11 KV Pin Insulator should be suitable for use with Galvanised Steel Pins conforming to reference S-165 of IS:2486 (Part-II) of 1974 with shank length 150 mm which is provided with a small steel head. Similarly, the thimble of 33 KVPin Insulator should be suitable for use with 33 KV Galvanised steel Pins conforming to reference I-300-N of fig. 6 with shank length of 150 mm and with large head of ISS-2486 (Part-II) of 1974. 5. INSULATOR CHARACTERISTICS:- The insulator shall have the electrical and mechanical characteristics which are given below:- The test voltage of insulator shall be as under:- 11KV PIN 33KV PIN INSULATOR INSULATOR 1. Highest system voltage 12KV (rms) 36 KV (rms) 2. Wet Power frequency 35 KV (rms) 75 KV(rms) withstand voltage test for one minute 3. Visible discharge voltage 9 KV (rms) 27 KV (rms) 4. Power frequency puncture 105 KV (rms) 180 KV (rms) withstand voltage 5. Impulse withstand voltage 75 KV(peak) 170 KV (peak)


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(In the above standards, power frequency voltage is expressed as peak values divided by 2 and impulse voltage is expressed as peak value) 6. The withstand and flash over voltage are referred to the reference atmospheric conditions. 7. Mechanical Loads Minimum Failing Loads i. 11 KV Pin Insulator 5 KN ii. 33 KV Pin Insulator 10 KN 8. DIMENSIONS AND CREEPAGE DISTANCE:- The insulators shall have the following dimensions and minimum creepage distance for a moderately polluted atmosphere:- Particulars 11 KV Pin Insulator 33 KV Pin Insulator (A) Dimensions i. Height 130 MM 210 MM ii. Diameter 125 MM 275 MM (B) Creepage Distance 230 MM 580 MM 9. TESTS:- The insulator shall comply with the following tests as per IS-731-1971. 9.1 TYPE TESTS:- The following constitute the type tests :- a. Visual examination b. Verification of dimensions c. Visible discharge test d. Impulse withstand voltage test e. Wet power frequency withstand voltage test f. Temperature cycle test g. Mechanical failing load test h. Puncture test i. Porosity test j. Galvanising test. Type test certificate from recognized Govt. lab for the tests carried out on prototype of same specifications shall be enclosed with the tender. The type test certificates shall not be more then 5 years old from the date of opening of tender. 9.2 ROUTINE TESTS:- The following shall be carried out as the routine tests:- a. Visual examination b. Electrical Routine tests c. Mechanical Routine tests 9.3 ACCEPTANCE TESTS:- The test samples after having withstood the routine tests shall be subjected to the following acceptance tests in the order indicated below:- a. Verification of dimensions b. Temperature cycle test c. Mechanical failing load test d. Puncture test e. Porosity test f. Galvanising test 9.4 Tolerance in insulator dimensions shall be as per the relevant Indian Standard i.e. (0.04d+1.5) mm when d 300 mm and where d is the dimension in mm. 10. MARKING:- Each insulator shall be legibly and indelibly marked to show the followings:- a. Name and trade mark of manufacturer b. Month and year of manufacture c. Minimum failing load in newtons d. Country of manufacture


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Marking on porcelain shall be printed/engraved and shall be applied before firing. 11. PACKING:- All insulators shall be packed in wooden crates suitable for easy but rough handling and acceptable for rail and road transport.

12. STANDARDISATION OF DIMENSIONS OF TOP AND NECK OF 11 KV PIN INSULATOR Please note that now-a-days Board is using preformed ties for binding conductor with the Pin

Insulator instead of conventional method of binding by aluminium binding wire and tape. The design of the preformed ties depends upon the dimensions of top and neck of 11 KV Pin Insulator. For proper gripping of the conductor with the help of preformed fittings it has become necessary to standardise the dimensions of the insulator top and neck. Accordingly, a drawing 051-32/CSEB/1 dt.1.9.2001, which indicates the standardised dimensions of top and neck of 11 KV Pin Insulator is enclosed with Tender Specification. This drawing has been approved by REC, New Delhi, therefore, the tenderers are advised to offer material based on this drawing.

TECHNICAL PARTICULARS FOR 11KV PIN INSULATORS --------------------------------------------------------------------------------------------------------------. Sno. Particulars 11KV Pin Insulator --------------------------------------------------------------------------------------------------------------. 1. Makers name & Country 2. Electrical Characteristics

a. Nominal system voltage 11 KV (rms) b. Highest system voltage 12 KV (rms) c. Visible discharge voltage 9 KV (rms) d. Dry one minute power frequency 55 KV (rms) withstand voltage e. Wet one minute power frequency 35 KV (rms) withstand voltage f. Power frequency puncture 105 KV (rms) g. Impulse (1/50 micro second 75 KVP wave) Voltage h. Impulse flashover (1/50 micro 108 KVP second wave) voltage negative i. Impulse flashover (1/50 micro 124 KVP second wave) voltage negative j. Dry flashover voltage 60 KV k. Wet flashover voltage 40 KV 3. Mechanical characteristics: a. Minimum falling load 5 KN b. Minimum creepage distance 230 mm 4. Colour of glaze Brown 5. Size of insulators: a. Height 130 mm b. Diameter 125 mm 6. Standard according to which As per IS:


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porcelain insulator shall be 731/1971 manufactured and tested 7. Tolerance in dimensions if any As per ISS 8. Weight per unit of a. Porcelain Part To be indicated b. Thimble To be indicated ----------------------------------------------------------------------------------------------------------------.

TECHNICAL SPECIFICATION OF 33 KV GS PINS

1. SCOPE : The specification provides for manufacture & testing of 33 KV GS Pins suitable for Pin Insulators, complying with Indian Standard Specification No.IS:2486 (Part-I) 1971, IS:2486 (Part-II & III) 1974 and the latest version thereof. 2. GENERAL REQUIREMENTS FOR 33 KV GS PINS :- 2.1 The Pins shall be a single piece obtained by the process of forging. They shall not be made by jointing / welding / Shrink fitting of any other process from more than one piece of materials. They shall be of good finish free from flaws and other defects. The finish of the collar shall be such that a sharp angle / edges between the collar and the shank is avoided and the collar or the seating surface shall be down correctly on to the cross arm when fixed to that through a hole the diameter of which is 2 mm greater than the diameter of the shank. 2.2 All ferrous pins & nuts shall be galvanized by the hot dip process. Other fittings i.e. flat washers and spring washers may be electro galvanized as per Clause.5.2.3 of IS: 2486 (Part-I) & subsequent amendments, if any, and should satisfy the tests as per IS: 1573 of 1986 and subsequent amendments (if any). The threads of nuts and taped holes when cut after galvanizing shall be well oiled or greased. 2.3 The Pins shall be as per relevant figure indicated in IS: 2486 (Part-II) with small / large steel heads and shall match with the Pin type insulators with cemented zinc thimble having similar threads. 3. MARKING :

Each and every material shall be legibly and indelibly and marked with NAME OR TRADE MARK of the manufacturer and suitable identification mark like property marking CSEB should be engraved / embossed. 4. TEST & TEST CERTIFICATES: TYPE TEST CERTIFICATE: Notarized type test certificate giving the results of samples tested for the tests, as per Clause-4.3.1 of IS:2486 (Part-I) 1971 for the item quoted, shall compulsorily be enclosed by the tenderer alongwith their offer in support of evidence of compliance of the specifications and guaranteed particulars.

TYPE TEST : a) Freedom from defects, b) Verification of dimensions, c) Galvanising test (both uniformity of Zn.coating and Wt.of Zn.coating). d) Mechanical tests, e) Chemical composition test, Type test shall be made and certified by any Govt. recognized authority.

5. ROUTINE TEST: The test certificate of the lot giving the results of routine tests as per requirement of Clause-4.3.3 of IS:2486 (Part-I) 1971 shall have to be submitted invariably by the firms alongwith the offers of materials being made by them for pre-despatch inspection of the materials.


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6. ACCEPTANCE TEST: (Test to be carried-out during pre-dispatch inspection)

(i) The dimensional requirement of 33 KV GS Pins offered for pre-despatch inspection shall be checked and verified as per IS:2486 (Part-II)/1974 and the following tests shall be carried-out and witnessed by the Inspecting Officer during inspection of the material as per requirement of the IS:2486 (Part-I) 1974.

(ii) Checking of threads on heads: The dimensions of the threads on the heads of Pins shall be checked and verified by means of gauges (Ref.IS:2486 (Part-II)/1974.

(iii) Galvanizing Test: The uniformity of Zinc coating and Wt. of Zinc coating for Pins and Nuts shall be verified as per requirements of IS:2633/1972.

(iv) Mechanical test: This test shall be conducted in accordance with the Clause-4.6 of IS:2486 (Part-I) 1971.

(v) Visual Examination Test:- All the pins shall be checked visually for its good workmanship and finishing.

All the relevant Indian Standard Specifications (ISS) shall be made available by the firms invariably to the inspecting officer for reference while carrying out the pre-despatch inspection of the lot.

The Technical Particulars of 33 KV GS Pins are indicated in the Schedule-I B enclosed and these shall be required to be met out on inspection of the material.

7. LOT :-

All the GS Pins of same type and design manufactured under similar conditions of production offered for acceptance, a lot may consist of whole or part of the quantity offered.

A lot shall consist of only one type of fittings manufactured essentially from the same raw

material and under identical conditions. 8. PACKING :

The materials are to be packed in gunny bags, each bag containing 25 nos. of 33 KV Pins. 9. DRAWING :-

Two sets of detailed drawing (s) of the products(s) shall have to be submitted along with offer and again two sets along with acceptance letter on issue of LOI for approval before issue of detailed order.

10. TOLERANCE: All applicable as per latest edition / amendments of IS:2486 (Part-I).

TECHNICAL REQUIREMENTS S.N. PARTICULARS REQUIREMENT OF 33 KV GS PINS 1. I Dimensions Shall conform strictly to reference L-300-N of Figure-6 of

IS:2486 (Part-II) 1974. II Pins & Studs The forged pins & studs shall be of steel complying with

class:2 of IS:2004/1962. III Nuts The nuts shall be made of material conforming to property

class 4.8 of IS:1367/1983(Part-xiii) with regard to its mechanical properties.


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IV Steel Head This shall be as per Fig.1-B (large steel head) of IS:2486 (Part-II/1974 suitable for use with indigenous 33 KV Pin Insulators

V Nuts, Flat & spring washers a) Nuts shall be hot dip galvanized, b) One flat washer & spring washer shall be provided with each pin. Both these washers shall be electro galv. as per Clause- 5.2.3 of IS:2486 (Part-I).

VI Failing load Minimum 1080 kg.(10 KN) VII Drawing ref.of IS:2486 (Part-II) i) Fig.No.6,

ref. No. L-300N ii) Fig.No.1 (B)

2 Dimensional Requirements 33 KV GS Pins I Length of stalk 300 mm II. Bottom diameter of stalk 44 mm III Top diameter of stalk 27 mm IV Length of shank 150 mm V. Diameter of shank 24 mm VI Length of threaded portion in

the shank 100 mm

VII Length of threaded portion of stalk

47 mm

VIII Thickness of collar 6.00 mm IX Diameter of collar 67 mm X Tolerance i. No negative tolerance is permissible for Dip test & Mass

of Zinc coating, ii. +/- 5% (Plus Minus five percent) shall be allowed in all the dimensions except in thickness of collar and threaded portion of stalk.

3 Method of Galvanizing As per IS:2633/1972 (Hot dip for both 11 KV & 33 KV Galvanizing GS Pins)

TESTS FOR GS PINS FOR GI NUTS I Dip test 4 dips of 1 minute each 4 dips of 1 minute each ii. Mass of zinc coating 300 gms/m2 (Minimum) 300 gms/m2 (minimum) The mass of zinc coating on Pins shall be as per Clause-4

of IS:4759-1979 and in case of Nuts shall be as per Clause No.4 of IS:1367 (Part-XIII)-1983. The above tests shall invariably be conducted during all routine inspection of material (S.No.I,II & III).

4 Applicable specifications: (with latest amendments, if any)

IS:2486 (Part-II) of 1974. IS:2486 (Part-I) of 1971, IS:4759-1979 and IS:1367 (Part-XIII)-1983 IS:2633-1972 IS:2004-1962

TECHNICAL PARTICULARS FOR GS PINS Sno. Particulars Requirement of 11 KV GS Pins 1. Dimensions Shall conform strictly to reference S-165-P of Figure-5 of IS: 2486

(Part-II) of 1974. 2. Pins & Studs The forged pins and studs shall be of steel complying with clause: 2

of IS: 2004/1962. 3. Nuts The nuts shall be made of material conforming to property clause

4.8 of IS: 1367/1983 (Part-xiii) with regard to its mechanical properties.

4. Steel Head This shall be as per Figure 1-A (small steel head) of IS: 2486 (Part-


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II) 1974 suitable for use with indigenous 11KV pin insulator. 5. Nuts, Flat & Spring Washers a) Nuts shall be not dip galvanised.

b) One flat washer & spring washer shall be provided with each pin. Both these washers shall be electro galvanised as per clause-5.2.3 of IS: 2486(Part-I)

6 Mounting arrangements Shall be suitable for mounting on 75x100mm M.S.Channel 7. Falling load Minimum 540 Kg. (5 KN) 8. Dimensional Requirements 11 KV GS Pins

I. Length of stalk 165 mm II. Bottom diameter of stalk 25 mm III. Top diameter of stalk 24 mm IV. Length of shank 150 mm V. Diameter of shank 20 mm VI. Length of threaded portion in

the shank 100 mm

VII. Length of threaded portion of stalk

44 mm

VIII. Thickness of collar 5.00 mm IX. Diameter of collar 40 mm 67 mm X. Tolerance i) No negative tolerance is permissible for Dip test & Mass of Zinc

coating. ii) 5% (Plus minus five percent) shall be allowed in all the dimensions except in thickness of collar and threaded portion of stalk.

9. Method of Galvanising As per IS: 2633/1972 (Hot dip for both 11KV Galvanising GS Pins) TESTS FOR GS PINS FOR GI NUTS

I. Dip Test 4 dips of 1 minute each 4 dips of 1 minute each 300 gms/m2 (Minimum) 300 gms/m2 (Minimum) II. Mass of zinc coating The mass of zinc coating on Pins shall be as per Clause-4 of IS:4759-1979 and in case of Nuts shall be as per Clause No. 4 of IS: 1367 (Part-XIII)-1983. The above tests shall invariably be conducted during all routine inspection of material (S.No. I, II & III).

10. Applicable specifications: (with latest amendments, if any).

IS: 2486 (Part-II) of 1974 IS: 2486 (Part-I) of 1971, IS: 4759 1979 and IS: 1367 (Part-XIII) 1983. IS: 2633 1972 IS: 2004 - 1962

TECHICAL SPECIFICATION OF11KV DISC INSULATOR

1. SCOPE:- This specification covers the design, manufacture, testing, supply and delivery of porcelain Disc Insulator for use on 11 KV and 33 KV overhead power lines. 2. STANDARD:- Except where they conflict with specific requirement in the specification, the Disc Insulator shall comply with the Indian Standard Specification IS:731/1971 and its amendment from time to time. The insulator conforming to any other internationally accepted standard which ensures equal or better quality than the above standard would also be acceptable. Where the material is offered according to the international standards, an English version of the specification shall be attached with the tender. 3. ATMOSPHERIC CONDITIONS:- 3.1 The material offered shall be suitable for operation under the climatic conditions indicated in Clause 31 of Annexure-II General Terms and Conditions of purchase appended with this tender specification.


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3.2 Reference atmospheric conditions at which insulator characteristics shall be expressed for the purpose of comparison shall be:- Ambient Temperature - 20 Degree Centigrade Barometric Pressure - 1013 millibars Absolute Humidity - 11 gms of water per cubic Meter corresponding to 63% Relative humidity at 20 Degree Centigrade Note:- A pressure of 1013 millibars is equivalent to a pressure of 750 mm of Mercury at 0 degree centigrade. 3.3 Tests for the purpose of this standard shall preferably be carried out under conditions of temperature and humidity specified in IS:196-1966 (i.e. at a temperature of 27+2 degree centigrade and relative humidity of 66+2 percent) and at the prevailing atmospheric pressure. When this is not possible, test may be carried out under conditions naturally obtained at the time of the test. The barometric pressure, air temperature and humidity shall be recorded for the purpose of correction. Corrections of test voltage for atmospheric conditions is given in Appendix A of IS:731-1971. 4. GENERAL REQUIREMENTS:- The porcelain shall be sound free from defects, thoroughly vitrified and smoothly glazed. 4.1 Unless otherwise specified, the glaze shall be brown in colour. The glaze shall cover all the porcelain parts of the insulator except those areas which serve as supports during firing or are left unglazed for the purpose of assembly. 4.2 The design of insulator shall be such that stresses due to expansion and contraction in any part of the insulator shall not lead to deterioration. The porcelain shall not engage directly with hard metal. 4.3 Cement used in the construction of the insulator shall not cause fracture by expansion or lossening by contraction and proper care shall be taken to locate the individual parts correctly during cementing. The cement shall not give rise to chemical reaction with metal fittings and its thickness shall be as unifom as possible. 5. TYPE OF INSULATOR:- The insulator shall be of type B according to its construction which is defined hereunder:- Type B:-An insulator or an insulator unit in which the length of the shortest puncture path through solid insulating material is less than half the length of the shortest flash over path through air outside the insulator. 6. INSULATOR CHARACTERISTICS:- 6.1 The insulator shall have the electrical and mechanical characteristics which are given below:- The test voltage of insulator shall be as under:- Disc Insulator 1. Highest system voltage 12 KV (rms) 2. Wet power frequency withstand 35 KV (rms) voltage for one minute 3. Visible discharge voltage 9 KV(rms) 4. Power frequency puncture withstand voltage 105 KV (rms) 5. Impulse withstand voltage 75 KV(peak) 6.2 In this standard, power frequency voltage are expressed as peak values divided by 2 and impulse

voltage are expressed as peak value. 6.3 The withstand and flash over voltage are referred to the reference atmospheric conditions. 6.4 Minimum Failing Load 45 KN 7. DIMENSIONS:- 7.1 The insulator shall have the following dimensions:-

Diameter - 254 mm Height -146 mm (Hole to Hole)


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7.2 CREEPAGE DISTANCE:- The insulator shall have minimum 320 mm creepage distance for a heavily polluted atmosphere. 8. TESTS:- The insulators shall comply with the following tests as per IS:731-1971 with its latest amendments. 8.1 TYPE TESTS:- The following constitute the type tests : a. Visual examination b. Verification of dimensions c. Visible discharge test d. Impulse voltage withstand test e. Wet power frequency withstand voltage test f. Temperature cycle test

g. Electro-Mechanical failing load test h. Puncture test i. Porosity test j. Galvanizing test. Type test certificate from recognized Govt. lab for the tests carried out on prototype of same specifications shall be enclosed with the tender for each type test failing which the tenders are liable for rejection. The type test certificates shall not be more than 5 years old from the date of opening of tender.

8.2 ROUTINE TESTS:- The following shall be carried out as the routine tests:- a. Visual examination b. Electrical Routine tests c. Mechanical Routine tests 8.3 ACCEPTANCE TESTS:- Acceptance of samples after having withstood the routine tests shall be subjected to the following acceptance tests in the order indicated below:- a. Verification of dimensions b. Temperature cycle test c. Electro Mechanical failing load test d. Puncture test e. Porosity test f. Galvanizing test 8.4 Tolerance in insulator dimensions shall be as per the relevant Indian Standard, i.e. (o.04d+1.5)mm when d300 mm and where d is the dimension in mm. 9. MARKING:-

Each insulator shall be legibly and indelibly marked to show the followings:- a. Name and trade mark of manufacturer b. Month and year of manufacture c. Minimum failing load in new tons d. Country of manufacture

Marking of porcelain shall be printed/engraved and shall be applied before firing. 10. PACKING:- All insulator shall be packed in wooden crates suitable for easy but rough handling and acceptable for rail and road transport. TECHNICAL PARTICULARS OF 11 KV DISC INSULATORS


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1. Makers name & country : 2. Type of Insulator : 3. Electrical Characteristics: a. Nominal system voltage : 11 KV (RMS) b. Highest system voltage : 12 KV (RMS) c. Visible discharge voltage : 9 KV (RMS) d. Dry one minute power frequency : 70 KV (RMS) withstand voltage e. Wet one minute power frequency : 40 KV (RMS) withstand voltage f. Power frequency juncture : 110 KV (RMS) withstand voltage g. Impulse withstand (1.2/50 : 100 KVP microsecond wave) voltage positive h. Impulse withstand (1.2/50 : 100 KVP microsecond wave)voltage negative i. Impulse flash over (1.2/50 : 105 KVP microsecond wave)voltage positive j. Impulse flash over (1.2/50 : 110 KVP microsecond wave)voltage negative k. Dry flash over voltage : 75 KV (RMS) l. Wet flash over voltage : 45 KV (RMS) 4. a. Minimum creepage distance : 320 mm b. Minimum failing load : 45 KNK 5. Colour of glaze : Brown 6. Size of Insulator a. Outer diameter : 255 mm b. Spacing : 145 mm 7. Net weight : 4.5 Kg. (Approx) 8. Standard according to which : IS 731/1971 porcelain insulator shall be manufactured and tested 9. Tolerance in dimensions, if any : As per ISS TECHNICAL SPECIFICATION FOR STRAIN HARDWARE FITTINGS FOR 11 KV &

33 KV LINES SUITABLE FOR USE WITH TONGUE AND CLEVIS DISC

INSULATORS (CONVENTIONAL TYPE FITTINGS)

1. SCOPE : This specification provides for manufacturers, testing before dispatch and delivery of materials listed in Schedule-I at the specified destination. 2. TEST CERTIFICATE: The following shall constitute the type tests for clamps:

(a) Visual examination, (b) Verification of dimensions, (c) Slip strength tests, (d) Ultimate strength tests, (e) Galvanizing / Electroplating tests.


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The type tests are intended to prove the general qualities and design of a given type of 33 KV & 11 KV Hardware fittings. These tests should not have been conducted earlier, than 5 years from the date of opening of tender. One copy of same should be submitted alongwith the offer otherwise the offer is liable to be rejected.

ii) ACCEPTANCE TESTS: The following shall constitute the acceptance tests : a) Visual examination tests, b) Verification of dimensions, c) Galvanizing / electroplating test, d) Mechanical tests, e) Ultimate strength test, The acceptance tests shall be carried out on all the samples taken from a lot for the purpose of acceptance of lot. iii) ROUTINE TESTS: The following shall constitute the routine test, a) Visual examination tests, b) Mechanical routine tests on Conductor Tension clamp only. The routine tests will be carried out on each of insulator fittings to check requirement, which are likely to vary

during production. All the above three tests have been described in IS:2486 (Part-I) 1993. Galvanizing tests

for Hot Dip Ferrous material shall be carried-out in accordance with IS-2633/1986 and satisfy the requirements in IS:4759/1984. Electro-galvanized ferrous fittings shall be

checked in accordance with IS:1573/1986. However, one sample from each lot will be tested as per IS:4759/1984.

11 KV STRAIN HARDWARE FITTINGS (T&C) TYPE : Each Hardware fittings of the Strain Insulators shall comprise of :- i) Hot dip galvanized cross arms and straps properly profiled suitable for use on 75/100 mm channel cross

arms with 16 mm dia, hot dip galvanized Bolts, Nuts spring washers, Plain washer and 4 mm dia split pin as per figures 26 of IS:2486 (Part-II) 1989 and its latest amendments:

ii) Snail type clamp with clevis eye suitable for 11 KV System for following sizes of Conductors :- (A) ACSR:- S.N. Item Stranding & Wire dia

meter (Aluminum + Steel)

Nominal Aluminum Area

i. ACSR Conductor (Squirrel) (6+1/2. 11 mm) 20 mm2 ii. ACSR Conductor (Weasel) (6+1/2.509 mm) 30 mm2 iii. ACSR Conductor(Rabbit) (6+1/3.35 mm) 50 mm2 (B) AAAC:- S.N. Item Stranding & wire dia of

AA Alloy Actual Area


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i. AAA Conductor (Squirrel) (7/2.00 mm) 22 mm2 ii. AAA Conductor (Weasel) (7/2.50 mm) 34 mm2 iii. AAA Conductor (Rabbi) (7/3.15 mm) 55 mm2 The ultimate strength of the clamp should not be less than 3000 kg. The clamp shall be made by

process of Die casting. The clamp with process of sand casting shall not be accepted. All dimensions of clevis and tongue connections shall be as per figure-25 of the IS:2486 (Part-II) 1989 and its

latest amendments. 5. GENERAL REQUIREMENTS: (A) All fittings of same type and design manufactured under similar conditions of productions. (B) All forging and castings shall be of good finish and free from f laws and other defects. The edges on the outside of fittings, such as the eye, clevis and holes , Shall be rounded.. The clamp shall be manufactured by the process of die casting or pressure die casting and

shall be free from blow holes and other defects. (C) All ferrous fittings and the part other than those of stainless steel shall be galvanized by the Hot Dip process. Only small fittings like, plain & spring washers, nuts may be electroplated galvanized. (D) The nuts shall conform to property 4.8 of IS:1367 (Part-6) 1980. (E) The cotter pins shall be provided with Galvanized Mild Steel Flat Washers in addition to split pins. (F) The split pin to be used on the cotter Pin shall be of phosphor bronze conforming to IS:7814/ 1975 or Stainless Steel conforming to IS:5577/1992 or brass conforming to IS:410/1977 with a minimum hardness of 160 HV. 6. MARKING ON CLAMPS : The clamps shall have the following markings for their identification as per IS: i) Trade Mark of manufacturer. Please note that the marking should be legible and permanent (preferable die casted). 7. PACKING :

Strain clamps and related hardware shall be packed in double gunny bags or wooden cases if deemed

necessary. The gross weight of the packing shall not exceed 50 kg. Different fittings shall be packed in different bags or cases and shall be complete with minor accessories fitted in place. All the nuts shall be hand tightened over the bolt and screwed up to the farthest point with split pin in position. The packing shall be fit to withstand rough handling during transit and storage at destination.

TECHNICAL SPECIFICATION FOR MS STAY SETS 16mm DIA

16 MM DIA BLACK STAY SETS FOR LT LINES (NON GALVANIZED, NOT-PAINTED): 1. The stay sets (Line Guy set) will consist of the following components:- i) Anchor rod with one washer and nuts: Overall length of rod should be 1800mm to be made out of 16mm MS rod, one end threaded upto 40mm length with pitch of 5 threads per cm and provided with one square MS washer of size 40x40x1.6mm and one MS Hexagonal nut conforming to IS:1367/1967 and IS:1363/1967. Both washer and nut to suit the threaded rod of 16mm dia. The other end of rod to be made into a round are having an inner dia of 40mm with best quality welding. Dimensional and other details are indicated in the enclosed drawing No.1 and details of welding are indicated below and also shown in the enclosed drawing No.4.


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ii) Anchor Plate Size 200x200x6mm: To be made out of MS plate of 6mm thickness. The Anchor plate should have at its center 18mm dia hole. iii) Turn Buckle : (a) Eye bolt with 2 nuts: To be made of 16mm dia MS Rod having an overall length of 450mm. One end of rod to be threaded upto 300mm length of pitch of 5 threads per cm and provided with two MS Hexagonal nuts of suitable size conforming to IS:1637/1967 & IS:1363/1967. The other end of rod shall be rounded into a circular eye of 40 mm inner dia with proper and good quality welding as described below and also shown in enclosed drawing No.4. (b) Bow with welded angle: To be made out of 16mm dia MS Rod. The finished bow shall have an overall length of 995mm and height of 450mm as shown in the enclosed drawing No.1. The apex or top of the bow shall be bent at an angle of 10 R. The other end shall be welded with proper and good quality welding to a MS angle 130mm long having a dimension of 50x50x6mm. The angle shall have 3 holes of 18mm dia each as per drawing No.1 enclosed herewith. Details of welding are indicated below and also shown in the enclosed drawing No.4. iv) Thimble: To be made on 1.5mm thick MS sheet into a size of 75x22x40mm and shape as per details given in attached drawing No.1. 2. WELDING: The minimum strength of welding provided on various components of 16mm dia stay sets shall be 3100Kgs. Minimum 6mm fillet weld or its equivalent weld area should be deposited in all positions of the job i.e. at any point of the weld length. The welding shall be conforming to relevant IS:823/1964 or its latest amendment. Minimum length of weld to be provided at various places in the stay sets shall be as shown in the enclosed drawing No.4. Welding if found short in lengths or not done properly as required shall be rejected. 3. THREADING: The threads on the Anchor Rod, Eye Bolt and Nuts shall be as per specifications IS:4218/1967 (ISO Metric Screw Threads). The nuts shall be conforming to the requirement of IS:1367/1967 & have dimensions as per IS:1363/1967. The mechanical property requirement of fasteners shall conform to property clause 4.6 each for Anchor Rod & Eye Bolt and property clause 4 for nuts as per IS:1367/1967. AVERAGE WEIGHT OF FINISHED STAY SETS: 7.702 Kg. (Minimum) (EXCLUDING NUTS, THIMBLES & WASHERS): 8.445 Kg. (Maximum) i) Anchor rod with one washer and nuts: Overall length of rod should be 1800mm to be made out of 16mm MS rod one end threaded upto 40mm length with pitch of 5 threads per cm and provided with one square MS washer of size 40x40x1.6mm and one MS Hexagonal nut conforming to IS:1367/1967 and IS:1363/1967. Both washer and nut to suit the threaded rod of 16mm dia. The other end of rod to be made into a round are having an inner dia of 40mm with best quality welding. Dimensional and other details are indicated in the enclosed drawing No.2 and details of welding are indicated below and also shown in the enclosed drawing No.4. ii) Anchor Plate Size 200x200x6mm: To be made out of MS plate of 6mm thickness. The Anchor plate should have at its center 18mm dia hole. iii) Turn Buckle : (a) Eye bolt with 2 nuts: To be made of 16mm dia MS Rod having an overall length of 450mm. One end of rod to be threaded upto 300mm length of pitch of 5 threads per cm and provided with two MS Hexagonal nuts of suitable size conforming to IS:1637/1967 & IS:1363/1967. The other end of rod shall be rounded into a circular eye of 40 mm inner dia with proper and good quality welding. Welding details are specified below and also shown in enclosed drawing No.4. (b) Bow with welded angle: To be made out of 16mm dia MS Rod. The finished bow shall have an overall length of 995mm and height of 450mm as shown in the enclosed drawing No.2. The apex or top of the bow shall be bent at an angle of 10 R. The other end shall be welded with proper and good quality welding to a MS angle 180mm long having a dimension of 65x65x6mm. The angle shall have 3 holes of 18mm dia each as per drawing No.2 enclosed herewith. Details of welding are indicated below and also shown in the enclosed drawing No.4. iv) Thimble: To be made on 1.5mm thick MS sheet into a size of 75x22x40mm and shape as per details given in attached drawing No.2.


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II. TOLERANCES: The tolerances for various components of the stay sets are indicated below subject to the condition that the average weight of finished stay sets of 16 mm and 20mm dia excluding nuts & thimbles and washers shall not be less than the weight specified above:- -----------------------------------------------------------------------------------------------------------------------------. SNo. Item Section Fabrication Material Tolerances Tolerances ----------------------------------------------------------------------------------------------------------------------------. 1. Anchor Plate 6mm thick +12.5% 200x200 mm MS plate 6mm - 5% + 1% Thick 8mm thick +12.5% 300x300 mm MS plate 8mm - 5% + 1% Thick 2. Anchor Rod 16mm dia + 5% Length 1800mm MS Round 16mm - 3% + 0.5% dia Round Eye 40mm MS Round 16mm inside dia + 3% dia Threading 40 mm

+ 11% - 5% 20mm dia + 3% Length 1800mm MS Round 20mm - 2% + 0.5% dia Round Eye 40mm inside dia + 3% Threading 40mm

+ 11% - 5% 3. Turn Buckle 16mm dia + 5% Length 995mm MS Round 16mm Bow - 3% +1% 16mm dia dia Length 180mm MS angle +1% 50x50x6mm Length 180mm MS Angle +1% 65x65x6mm Channel length MS Channel 200 mm + 1% 100x50x4.7mm 4. Eye Bolt Rod 16mm dia + 5% Length 450mm MS Round 16mm - 3% +1% dia Threading 300mm +1% Round Eye 40mm inside dia +3%.

20mm dia + 3% Length 450mm MS Round 20mm - 2% +1% dia Threading 300mm +1% Round Eye 40mm inside dia +3%. ---------------------------------------------------------------------------------------------------------------------------. TECHNICAL SPECIFICATION: 20 MM DIA BLACK STAY SETS FOR 33 KV LINES

(NON GALVANIZED, NOT-PAINTED):

AVERAGE WEIGHT OF FINISHED STAY SETS: 7.922 Kg. (Minimum

Documents

Technical Specifications 11kv