SPL REPAIR REPLACEMENT OF VINTAGE TRANSFORMERS AGAINST BER AT SITE R AT AF STN THANE

Supply and install, testing and commisioning of outdoor transformer as per IS : 1180 Part-I, level-II step down, copper wound 22 KV/433 Volts (at no load) AC 3 Phase 50HZ 250KVA capacity, core type, oil immersed naturally air cooled, oil natural, air natural (ON/AN), with external cooling tubes, delta connected on primary side (HV) and star connected on secondary side (LV) in accorance with vector ground DYn-11 with neutral brought out on secondry sied (LV) and having taping at +5% to -10% in steps of 2.5% on HV side to be changed by means of hand operated off load tap chargege gear. The max temp rise should not exceded 40 degree celsius in oil and 45 degree celsius in HV/LV winding when measured by resistance method after continuous full load run on and ambient temp of 40 degree celsius. Transformer shall be of BOLTLESS core design. Transformer shall be double wound, core type with low loss, non ageing, high permeablity prime grade cargo with M4 grade or better, perfectly insulated and clamped to min noise and vibrations. The transformer shall be IS/IEC 60076 and as per IS-1180 Part -I of 2014 marked and shall comprise of the following:- (a) One cable box on HT side (Primary side consisting of three nos porcelain bushing with copper rods, complete with nuts and washer, with cable glands suitable for reception/taking out HT 22000 volts grade XLPE insulated and PVC sheathed, heavy duty, armoured cables including jointing materials complete.

Description of Srl Item No 1.00 Contd/- (b) One cable box on LT side (secondary side) consisting of four nos porcelain bushing with copper rods, complete with nuts and washers, with cable grands suitable for reception/taking out single core 400sqmm, LT 1100 volts, grade, XLPE insulated and PVC sheathed, heavy duty, armoured cables including jointing material complete. (c) Conservator with filter type drain valve and oil level gauge. (d) De-hydrating breather with first fill of dehydrating agent (Silica Gel).(e) Explosive vent, Thermometer pocket on tank cover, Oil level gauge, Oil drain filter valve, lifting ligs, oil filling hole with cap/plug iwht connection plate complete, air release valve plug and four nos plain solid cast steel detachable rollers. (f) One no 100mm diea, dial type thermometer, vapour pressure type, having range 0-120 degree celsius with metal gaurd having max perimeter temp rading indicator with re-setting device. (g) Two earthing terminals on tank cover to facilitate fixing of 20x3 copper earth strip for earting of body.(h) Rating plate and terminal making plate.(j) Extra bushing for neutral in the LT cable box for providing independent set of earthing for neutral.(k) First fill of new and unused transformer oil, IS-335 of 1986 marked, filtered and tested upto 50KV dielectric strenght at 2.5mm air gap between testing electrodes, specific resistance at 27 Degree celsius Ohm-m 1500x10 to the power 12, water content 50PPM, Dielectric dissipation factor (tan Deta at 90degree celsius) 0.005, Neutralisation value mg of KOH/gm of oil 0.03 Inter facial tension N/M at 27 degree celsius - 0.04, flash point 140 degree celsius and sluge 0.1% by weight.

Description of Srl Item No 1.00 Contd/- (l) Providing adequate size and nos of channels, embeded in floor, for movement of transformer. (m) Transformer losses hall not exceed the losses not exceed 5% of mentioned in Table 6 of IS : 1180 of 2014 Part-I. (n) Oil temperature indicator.

M& L for providing earthing complete with Copper earth plate electrode 600 mm x 600 mm x 3.15 mm thick buried directly in ground earth pit not less than 2.25 Mtr deep below ground level with top edge of the plate not less than 1.5 Mtr below normal ground level connected to copper earth strip 20 x 3 mm by means of bolts, nuts, checknuts & washers of copper and connecting to test point , providing charcoal and common salt ,all as shown in electrical plate No. 3 of SSR Part I of 2009 & as specified or indicated and testing on completion including excavation/earth work in any type of strata PCC ( 1:3:6 ) type C1 earthing chamber, pre cast slab 50 mm thick in cement concrete ( 1: 2 : 4 ) type B1 (reinforced with welded steel wire fabric (XPM) weight not less than 4 Kg / Sqm), funnel with wire mesh, watering pipe of 20 mm bore medium grade and lugs, including copper earth strip 20 x 3 mm with GI protection pipe of 25 mm medium grade 7.5 meter long, etc complete all as specified. Note-- (i) Vendors are bound to get earthing result less than 1 Ohm with single earthing, Any additional work and material required to achive the required result is included in the cost. (ii) Excavated material to be removed from the site and deposit at the distance not exceeding 50m distance and levelled. (iii) Refill the pit

M&L for providing earthing complete with Copper earth plate electrode 600 mm x 600 mm x 3.15 mm thick buried directly in ground earth pit not less than 2.25 Mtr deep below ground level with top edge of the plate not less than 1.5 Mtr below normal ground level connected to copper earth strip 32 x 6 mm by means of bolts, nuts, checknuts & washers of copper and connecting to test point , providing charcoal and common salt ,all as shown in electrical plate No. 3 of SSR Part I of 2009 & as specified or indicated and testing on completion including excavation/earth work in any type of strata PCC ( 1:3:6 ) type C1 earthing chamber, pre cast slab 50 mm thick in cement concrete ( 1: 2 : 4 ) type B1 (reinforced with welded steel wire fabric (XPM) weight not less than 4 Kg / Sqm), funnel with wire mesh, watering pipe of 20 mm bore medium grade and lugs, including copper earth strip 32 x 6 mm with GI protection pipe of 40 mm medium grade 7.5 meter long, etc complete all as specified. Note-- (i) Vendors are bound to get earthing result less than 1 Ohm with single earthing, Any additional work and material required to achive the required result is included in the cost. (ii) Excavated material to be removed from the site and deposit at the distance not exceeding 50m distance and levelled. (iii) Refill the pit ,complete all as specified and as directed by Engineer-in-Charge.

M&L for platform for transformer of size 2000mm x 1500mm x 1200mm with brick masonry construction in cement mortar 1:4 PCC (1:4:8) type D-2, 150mm thick as in foundation, PCC(1:2:4) type B-1, 40mm thick as in floor over sub base PCC (1:4:8) type D-2, 75mm thick, brick masonry step on one side to made access to the top of platform including excavation & earth work in any type of soil including 15mm plastering to brick masonry in 1:4 and applying two coatsof synthetic enamel paint over a coat of red oxide primer on steel surfces and two coats of white wash on plasterd surface ,complete all as specified and as directed by Engineer-in-Charge.

Excavation in Trenches not exc. 1.50m width and n. exc 10 Sqm on plan and n exc 1.50mdepth depth and getting out in Soft / Loose soil ,complete all as specified and as directed.

Returning, filling including spreading, leveling, watering and well ramming, in layers not exc 25 cm complete all as specified and as directed by the Engineer-in-Charge.

Removing excavated soil to a distance not exc. 50 meter and depositing where directed at a level not exc.1.5 metre above the starting point complete all as specified and as directed by the Engineer-in-Charge.

M&L for sand cushioning for underground cable using fine sand 8cm before laying cable and 15cm after laying and punned to 180mm after laying of cable complete all as specified.(Note: Punned thickness shall be considered for payment purpose)