NIT No-22 EE (SDW) II/ (19-20) Item No. 10

Renovation of Primary Settling Tank of 12MGD STP Okhla by carrying out following works:- Isolating the PST by operating sluice gate and providing gunny bags to ensure no flow in the PST. Dewatering the PST with the help of sump pumps etc. Cleaning the PST with the help of machines/manually for execution of work.

Dismantling of electric motor, primary gear box and other mechanical accessories from the top of centres mechanism and shifting to workable place.

Making temporary platform as safety measures on the side of the central cage as per site requirement for dismantling of derive head.

Dismantling of central cage & turn table, lifting & taking out from the PST & shifting to ground level etc.

Dismantling the damaged structure of the both side scrapper arm structure by cutting the nut-bolts with gas cutter and shifting the same to a workable place with the help of mobile crane & heavy Labour tec.

Renovation of centre drum i/c replacement of the damaged stiffeners of the drum and making required patch work with 6 mm thick M.S. sheet (approx. 15 sqm) with the help of electric welding , gas cutter etc as per site requirement.

Overhauling/Servicing of the primary reduction gear box fixed on the top and central mechanism i/c replacement of damaged spares of the gear box and central mechanism, the job also include replacement of bearings (roller/ball) & gear oil etc. for the same.

Renovation and strengthening of scrapper arms structure by way of providing / fixing new elements of the structure made out of M.S. angle iron of size 65x65x8 mm & 50x50x8 mm by using new fasteners and homogenous electric arc welding and balancing the both side arm with the help of tie rod and with adjustment bolts.

Replacement / Renovation of the bottom scrapper made out from 8 mm thick M.S. sheet of size 200x1700 mm approx. i/c replacement of the rubber squeezers with M.S. flat after making holes at equal distance and fastening through the nut bolts.

Dismantling the v-notch of the PST and refixing the same by replacement of damaged nut bolts(approx. 165 nos.) with the help of gas cutter, drilling holes etc. in the RCC wall of PST and making proper leveling and alignments.

Fabrication the scum box (size 1800x1500 mm approx) made out of 6 mm thick M.S. sheet i/c providing the heavy duty out let pipe of 200 mm dia and 8 mm thick, including flange with nut bolts &gasket. Fixing the box at site with the help of angle / channel after alignment the scum box with the help of all tools and tackles and loading, unloading

Providing/ fixing of MS chequered sheet, 8 mm thick, 0.950 Mtr. Wide in a length of 20 Mtr. Apprx by cutting of old rusted / corroded sheet & fixing of new sheet with welding work.

Painting the complete structure by carrying out following works:- Providing the metal primer red oxide (in 20 Ltrs. Packing)

Providing the synthetic enamel paint Tractor Orange (in 20 Ltrs. Packing) Make:- Asian/Nerolec/Berger

Providing of thinner (General propose) for diluting the paint (in 20 Ltrs. Packing)

Painting the complete structure with one coat of epoxy primer and two or more coat of enamelled paint as per requirements.

Assembling, testing & commissioning of complete unit on NO load / full load after removing gunny bags and temporary plate form. The job also includes fixing up the new belt to motor-gearbox and varnishing of the motor with Dr. Beck Varnish.

MITTAL TRADING COMPANY