Fabrication and Replacement of Attack Scrubber Stack Bottom Course in PA Plant

Fabrication and Replacement of Attack Scrubber Stack Bottom Course in PA Plant

Prefabrication of Attack Scrubber Stack Bottom Course: Collect and transport required materials,tools and tackles for the work. Make necessary site arrangements. Fabricate bottom course of stack, ID 1110, approx height 7.0m by marking, cutting and rolling and welding 10 mm MS plate as per available drawing and exsting stack at site. The ends shall be prepared with single bevel for welding. All required flanges including foundation shall be fabricated out of 25mm MS plate, drilling to suit existing mating flanges at site and stack foundation at scrubber floor.Flanges shall be set on the stack as per existing design and full welded. Stiffners for flanges shall be fabricated out of 16mm MS plate (approx: 100 nos ) and full welded on the flange to stack area as per instructions from engineer in charge . The square flange and spool piece at the suction end shall be fabricated out of 16mm/10mm MS plate taking dimensions from exisiting stack and full welded to the stack. The flange drilling shall be as per mating flange at scrubber fan outlet at site. All the flanges shall be properly set without any tilts and levelled before welding. Any repair/replacement of mating flange on scrubber fan discharge at site shall be in contractor's scope. All welding shall be full welding only and 100% DP tetsed. All welding joints inside and outside shall be properly ground and made smooth to facilitate rubberlining. Erection hooks shall be fabricated and welded to stack with proper pad plates. Pad plates for welding monkey ladder is to be provided After the fabrication is complete transport the stack to earmarked area for rubberlining. Transportation of flanges to and fro workshop to drilling is under contractor's scope. Transportation and movement of stack for rubberlining/hotbonding as many as required will be under contractor's scope. Rubberlining of stack is not under the scope of this contract. Site shall be cleared after fabrication is complete and transport the scrap to scrapyard.

Dismantling and Erection of Attack Scrubber Stack Bottom Course : Collect the required materials,tools and tackles etc from store/workshop and transport to site. Make necessary site arrangements for the work. Hooks for dismantling shall be welded to bottom course of stack as per instructions.Dismantle the ladder and platforms on the stack. Dismanlte the flange joint on stack inlet.Unbolt the stack foundation bolts. Dismantle the entire stack course by course and transport it to the area earmarked. Reapair the ladder and platform as per instructions from engineer in charge. Any repair/patchwork of stack course pieces shall be done. Flanges (upto 6 no) shall be fabricated from 25mm plates and replaced if required. Stiffeners shall be fabricated from 16mm MS plate and welded on stack courses other than bottom course as per instructions from engineer in charge. Any mechanical repair on the foundation like replacement of base plates,foundation/base bolts etc shall be done. After complete dismantling and repairs of stack foundation, transport the new bottom course of stack to worksite. Erect the bottom course on the foundation. Align the foundation flange to existing base without any strain. Full tignten the foundation bolts.Align and match the suction square flange to scrubber fan outlet flange. Provide bolts and full tighten the bolts without any starin and with proper gasketting. After erection of bottom course of stack is complete and mating flanges are full tightned erect the subsequent pieces of stack one by one.The flanges shall be properly aligned and mated on each piece. Provide bolts and full tignten the flange joints. Ensure that the flange faces are properly seated without any strain and all bolts full tightned. Erect the monkey ladder and platform as per existing design and full weld on the pad plates. Any rework on the flanges, structurals etc during erection shall be done. After the erection is complete clear the site and transport the scrap to scrapyard. Main crane for dismantling of stack pieces and erecting back shall be under contractor scope. Other supporting crane and heavy equipments will be under FACT Scope, subject to availability.

VIKRAMAN NAIR S (BID ID -3258011)

AMMA CONSTRUCTION CORPORATION (BID ID -3259730)

M A ALI (BID ID -3258683)

M A Shamsudeen (BID ID -3258653)

BASHEER V P (BID ID -3259776)

PAREETH V V (BID ID -3259769)

M K ALIAS (BID ID -3259649)