removal and replacement of delivery pipes and valves etc . from existing size 350mm dia with new 500mm dia of pump no . 4 , 5 and 6 at pump house no . 1 ( old intake well ) , as per detail given below , cutting 350mm pipe of existing pump delivery line ( one cuts foreach pump x 3 pumps ) , surface cleaning & grinding of cutting face of existing pipeline , supply of ms co-centric enlarger of 450 x 500mm for enlarging delivery size 500mm , supply , aligning & welding of all positions with required number of runs for ms flange of 500 mm dia on ( is - 1536/1989 and upto dated amendments ) enlarger including gauging wherever necessary , fixing appurtenances and other accessories in connection with delivery pipe work as per specifications . , supply , aligning & welding of all positions with required number of runs for ms flange of 450mm on ( is - 1536/1989 and upto dated amendments ) enlarger including gauging wherever necessary , fixing appurtenances and other accessories in connection with delivery pipe work as per specifications . , supply , installation , testing & commissioning of corrugated design stainless steel expansion bellows pn 1 . 6 with flanges , 15mm axial movement , 300mm overall length with tie rods , nuts etc . of following class and diameter; including all taxes , octroi , inspection charges , freight charges , insurance , loading , unloading , conveyance to departmental stores , stacking etc . complete tender specifications; and b ) lowering , laying and jointing in position complete as per instructions of engineer in charge . 500mm dia for delivery pipeline , supply , installation , testing & commissioning of dual plate check valve pn 1 . 6 of approved make & confirming to api-594/598 and of following class and diameter; including all taxes , octroi , inspection charges , freight charges , insurance , loading , unloading , conveyance to departmental stores , stacking etc . complete; and b ) lowering , laying and jointing in position complete as per tender specifications and instructions of engineer in charge . 500 mm dia for delivery line , supply , installation , testing & commissioning of spirally welded/erw/saw/ fabricated 500mm dia m . s . tail piece ( commercial quality ) of suitable lengths including all taxes ( central and local ) , freight , insurance unloading , transport to stores/site unloading , stacking etc , complete as per is 3589 and is 5504 as applicable as specification . , cutting of hole in header line for fixing of 500mm delivery pipe . , supply & placing of ms plate for aligning & fixing of delivery pipe to header with filling of gaps . , supply & placing of rubber gasket of 500mm nominal diameter for flange joints . , supply & placing of rubber gasket of 450mm nominal diameter forflange joints . , supply & placing of high tensile steel nut+bolt+ washer set for fixing of 500mm valves & pipes with specials . , removal of dismantalled materials like pipes and valves etc . complete in all respect & transport to local stores including loading & unloading as per direction of engineer incharge