SPECIAL REPAIRS AND RENOVATION OF EARTHING PITS AT 57 RPA DET AT KUMBHIRGRAM UNDER GE SILCHAR

Amount

Taking down old unserviceable earthing of any description at any location and position and disposing off complete all as specified and as directed

Taking down old unserviceable earthing strips of any description at any location and position and disposing off complete all as specified and as directed

S&F copper strip of size 25x3.15mm with saddles and fixing screws, FRP insulators, etc. for roof conductors, down conductors and wall conductors above the ground, etc. brazed /welded at each joint complete all as specified and as directed

S&F copper strip of size 32x6mm with saddles and fixing screws, FRP insulators, etc. for roof conductors, down conductors and wall conductors above the ground, etc. brazed/welded at each joint complete all as specified and as directed

Supply, installation, testing and commissioning of maintenance free tripod earthing system consisting of 3Nos. vertical copper pipe (inner dia 50mm and outer dia 80mm) electrodes of 250micron copper bonded low carbon steel core of 3m long, 17.2mm dia buried directly in ground and tapered at the bottom (150-175 dia digging or auguring of earth to the required depth as directed), with 32x6mm copper strip (ETP grade) interconnected with earth electrode of UL listed tested along with a 20mm dia perforated PVC/GI watering pipe and filled up in bottom with slurry 3kg plain bentonite for moisture and based earth enhancing compound (having chemical composition bentonite-40%, copper sulphate-20%, gypsum-5%, graphite-10%, alum-5%, zinc sulphate-10% and aluminium sulphate-10%) and arrangement for connection of copper strip (32x6mm) to rod by means clamp rod to flat clamp of copper of size 50x6mm to the electrode tested for minimum 76% IACS, copper earth strip connected by means clamp, including necessary excavation in any type of soil, returning, filling in, removal of surplus soil, the rest of the bore shall be filled with well compacted earth and top of the bore shall be finished with 40mm thick PCC in 1:2:4 type B1 over 75mm thick PCC in 1:4:8 and filling in highly conductive and anti-corrosive back fill/JAM compound with 40mm thick pit and cover in PCC 1:2:4 type B-1, using 20mm graded stone aggregate reinforced with 8mm dia MS bars 3Nos. both ways complete all as specified and as directed

Notes for serial item No. 5: (i) The earthing shall comply to IS 3043, UL 467, BS/EN50164-7 (ii) The earth resistance shall be less than 1Ohm. A guarantee for 3years of this criterion on a Rs. 100 stamp paper shall be given by the Contractor. The quoted rate shall be deemed to be inclusive of this aspect (iii) To obtain earth resistance less than 1Ohm, if a combination two or more earthings are to be inter-connected or the length of the electrode/s is/are to be increased it shall be measured and paid as one earthing only (iv) UL listed testing shall be submitted alongwith data sheet, MTC and type test reports (v) Testing of earth shall be carried out in presence of Departmental rep and requisite test reports shall be submitted (vi) Cost of all excavation & earthwork required shall be deemed to be included in the quoted rate

S&F in repairs steel water tubing, light grade, 40mm bore, galvanized with screwed and socketed joints, in any length, including supply and fixing all fittings, ISI marked conforming to IS -1239 and fixed to walls or laid in floors / trenches as in cable protection, earthing strips, etc. complete all as specified and as directed

M&L for test point terminal block made of gun metal phosphorus bronze, size 75x75x25mm, drilled and screwed with sheet metal enclosure of size 100x100x100mm fabricated out of steel sheet not less than 1.6mm thick and including 3Nos. 8mm dia 25mm long hexagonal head screws including taking down old terminal block and disposing off complete all as specified and as directed

M/S M P Sharma