SPECIAL REPAIR/REPLACEMENT OF EARTHING INFRASTRUCTURE AT AF STN NAL

Amount

Taking down copper strip of any size fixed on the wall on batten or recess or chases or burried in ground or drawn in conduit /pipe through wall /floor /roof etc complete all as specified and as directed .

Taking down old unserviceable Air termination copper rod of any lsize from the roof etc complete all as specified and as directad

Supply & Fixing Air termination single pointed copper rod 12mm dia, and 300 mm long complete all as specified and directed by Engineer in charge .

Material & labour for copper strip 20 x 3.15 mm with proceline insulator and fixing screws etc for roof conductors and down conductors above the ground all as specified and directed.

Material & labour test point terminal block made of gun metal or phosphorus bronze size 75x75x25mm drilled and screwed including 3 nos. 8mm dia 25mm long hex. head screw complete all as specified and directed .

Supply & Fix 20 x 3 mm copper strip as earth continuity conductor or main earthing lead fixed to wall on batten or recess or chases or buried in ground or drawn in conduit / pipe through wall /floor / roof or fixed to poles or any other indicated situation for loop earthing etc. as required complete all as specified and as directed Note:- (i) Excavation & earth work shall be measured and paid for separately. (ii) Cutting holes in the wall and making good with cement plaster / mortar alongwith distemper / white wash is deemed to be included in the rate quoted. (iii) Cost of Insulators required for fixing of strip including nuts and bolts is also included in the unit rate quoted)

Supply & Fix epoxy based insulator 40mm height for fixing GI strip/copper strip on wall / ceiling / floor / poles etc. complete all as specified and directed by Engineer in charge . Note:- This item is considered for replacement of insulators other than those catered for unit rate of serial item No. 5here-in-before.

Supply & Fix High density polyethylene pipes (HDPE) of pressure rating 6 kgf/cm2 laid in trenches external dia 40mm, exclusive of boxes (junction / terminal) but inclusive of all tees, bends, elbows, reducers, bell mouth tube ends and fixing accessories such as couplers, lock nuts, saddles, pipe hooks etc. complete all as specified and directed .

Taking up or down steel tubing 40 mmm dia including all connections and fittings , complete all as specified and as directed.

All as per Item no 09 above bit for size 20 mm.

All as per Item no 09 above bit for size 15 mm.

Supply & Fix galvanised steel tubes 40mm bore medium grade with all fittings, laid in trenches / fixed to walls/poles with suitable clamps, nuts, bolts etc for passing of earth continuity conductor including necessary welding where required complete all as specified and directed by Engineer in charge .

All as per Item no 12 above but of size 20 mm dia pipe.

All as per Item no 12 above but of size 15 mm dia pipe.

Supply & Fix Bib tap of 15 mm dia standard of PTMT any colour high pressure screwed for iron pipe and fixed complete all as specified and directed. Note :- Taking down cost is included in item no 11 herein-in-before.

Taking down / out existing copper / GI strip as earth continuity conductor fixed to wall on batten or recess or chases or buried in ground or drawn in conduit/pipe or fixed to poles etc, incl straightening the twisted / bent up portion of strip and re-fixing in position complete all as specified and directed directed by Engineer in charge . Note:- Welding / soldering of earth continuity conductor where required shall deemed to be included in the unit quoted rate .

Material & labour for copper earth plate electrode 600 mm x 600 mm x 3.15 mm thick, burried directly in ground in vertical position, 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 ground level. The earth plate to be connetced with copper earthing strip of size 20 mm x 3 mm thick by means of brazing between copper strip and earth plate min 45 cm in vertical length and copper strip also to be joined by brazing only. The copper earthing strip to be protected by galvanised iron pipe 40 mm bore (medium grade) up to ground level and there after with 40mm dia HDPE pipe up to test point. Earthing shall include provision of funnel with 20mm bore galvanised iron pipe (light grade), wire mesh, charcoal or coke and common salt in alternate layer of 15cm (compacted thickness) up to 90 cm all around earth plate further filled with 60 cm thick Tibba sand and 2nd layer with 30 cm of Magnesium sulphate powder (compact thickness ), 3rd layer with tibba sand up to ground level. Earthing shall also include concrete earth pit in PCC (1:3:6) type C-1 (with 20mm graded ,crushed stone aggregate), 50mm thick precast RCC (1:2:4) cover slab (re-inforced with 8mm dia TMT bar @ 15 cm C/C bothways and suitable handle made of 10mm dia) including necessary earth work in excavation, returning filling and removal of surplus earth upto a distance not exceeding 50 Mtr etc all as shown on electrical plate No. 3 of MES Schedule Part-I complete to obtain less than 2 Ohm earth resistance value, including taking out exhisting GI Earthing complete all as specified and as directed.

NOTE : (i) Cost of this items includes the scope of earth work, charcoal, salt, PCC, RCC pit cover of required size including reinforcement. (ii) Tibba sand shall be arranged by the contractor at his own and the cost thereof shall be deemed included in unit quoted rate of this item. (ii) Electrical Plate No. 3 refrred in the item above is mainly for earth chamber. (iii) Cost of this item includes the scope of making test point terminal block complete.

M&L as in repairs chemical earthing complete with copper earth plate electrode 900 mm x 600 mm x 5 mm thick buried directly in ground vertically in a pit of depth not less than 3.65 metre below normal ground level with top edge of the earth plate at a depth not less than 2.90 metre below normal ground level, earth plate connected to copper strip 32 x 6 mm as earthing lead by means of running gas welding / brazing for a length of 45cm, copper strip protected by galvanized steel pipe 50 mm bore medium grade upto ground level and there after by 50 mm dia HDPE pipe upto test point (maximum upto 7.5metre from earth plate), earth plate surrounded by charcoal or coke and common salt upto 90 cm in alternate layers of 15cm each, thereover a layer of 60cm tibba sand duly compacted, thereafter 30 layer of magnesium sulphate powder (compacted thickness) and finally filing the top of pit upto ground level with tibba sand, to achieve earth resistance value less than 1 Ohm including provision of 20mm bore galvanised steel pipe 20mm bore light grade with funnel & wire mesh for watering, earth pit chamber built in cement concrete 1:3:6 type C-1 using 20mm graded stone aggregate covered with 50mm thick pre-cast cover slab of RCC 1:2:4 type B-1 duly reinforced with 8mm dia MS TMT bars @ 15cm c/c both ways, with suitable handle made of 10mm dia MS round bar, including excavation & earthwork in any type of soil / strata, removal of surplus soil to a distance not exceeding 50 metre as shown in Electrical Plate No. 3 of MES Schedule Part-I complete all as specified and directed.

Note for above item No. :- (a) On testing after completion, if the desired earth value i.e. less than 01 Ohm is not obtained, the earthing shall be re-carried out by contractor at no extra cost to the Govt. (b) The quantity of backfill material and depth of earth pit shall be added by the contractor to acheive earth resistance less than 1 ohm on completion and testing without any extra cost to Govt. (c) The rate quoted shall also include the cost of following:- (i) bronze test point of size 75mm x 75mm x 25mm. (ii) Display board of size 20cm x 15 cm made of 3mm thick MS sheet with frame and supports of angle iron 40mm x 40mm x 4mm, legs embedded in and including PCC blocks 30cm x 30cm x 15cm in 1:3:6 type C-1 incl necessary form work, earth work, painting MS work with synthetic enamel paint and marked with earth pit No. as directed. (d) The work shall be executed at different locations of AF Stn Nal. Conractor shall keep this aspect while quoting his rates. The locations of earthing is kept with AGE E/M AF Nal.

M&L for earthing complete with GI earth plate electrode 600 mm x 600 mm x 6 mm thick, burried directly and preferably vertically in ground, earth pit not less than 2.25 Mtr deep below ground level with top edge of the plate not less than 1.50 Mtr below ground level. The earth plate to be connetced with earth lead of 25x4 mm GI strip all as shown in para no 4 the earthing test point all as specified and directd.The GI earthing strip to be protected by galvanised iron pipe 40 mm bore (medium grade) up to ground level and there after with 40mm dia HDPE pipe up to test point. Earthing shall be include with providing funnel with 20mm bore galvanised iron pipe (light grade), wire mesh, charcoal or coke and common salt in alternate layer of 15cm (compacted thickness) up to 90 cm all around earth plate further filled with 60 cm thick Tibba sand and 2nd layer with 30 cm of Magnesium sulphate powder (compact thickness ) , 3rd layer with tibba sand up to the ground level. Earthing shall also be include for providing concrete earth pit in PCC (1:3:6) type C-1 (with 20mm graded , crushed stone aggregate), 50mm thick precast RCC (1:2:4) cover slab (re-inforced with 8mm dia TMT bar @ 15 cm C/C bothways and suitable handle made of 10mm dia) including necessary earth work all as specified and directed.

Supply and fixing as in repairs PVC insulated multistranded copper conductor cable 10 sqmm single core 1100 volts grade including copper lugs/thimbles on both side fixed from common Earth point to neutral point at main switch / earth dolly including nuts, bolts, washers complete all as specified and directed.

Excavation in trenches in soft/loose soil not exceeding 1.5 mtr wide and not exceeding 1.5 Mtr deep and getting out, forming bottom surfaces to required gradient complete all as specified and directeddirected by Engineer in charge .

Returning, filling in trenches including spreading leveling watering and well ramming in layers n.exc 25 cm thick complete all as specified and directed directed by Engineer in charge .

Removal of surplus soil to a distance not exc. 50 metre and depositing where directed at a level not exc. 1.50mtr above the starting point complete all as specified and directed directed.

Supply and fix GI pipe medium grade 40 mm dia of length 1.2 m to fixed on top of building structure to support Air termination including PCC 1:2:4 TYPE B-1 ( 20 mm graded crushed stone aggregate ) foundation 30x30x25 cm size , complete all as specified and as directed.

M&L for PCC 1:3:6 type C2 ( 40mm graded , crushed stone aggreegate for supporting of copper strip complete all as specified and as directed . Note :- PCC blocks of size 20mm x 20mm x30 cm to be provided for copper strip to be laid on the roof / blast pen walls .

RAJENDER ENTERPRISES

SHREE GURU NANAK CONSTRUCTION COMPANY