bids are invited for procurement of process valve , 4 f / e swing checkvalve ( ibr ) , 8 inch ( ibr ) cast carbon steel swing check valve, class-150 with flanged ends. , flanged end swing check valve. ( ibr ) , 18 inch ( 450 mm ) cast carbon steel double flanged bolted bonnet check valve design standardbs1868 , cs swing check valve with bolted cover , 2 inch cs bolted bonnet flanged end swing check valve as per mfg. std. bs 1868 and testing std. bs , cs swing check valve with bolted cover , 14 inch ( dn 350 ) cast steel wafer check valve suitable for mounting between flanges of ansi b16.5 6 inch ( dn 150 ) cast steel wafer check valve suitable for mounting between flanges of ansi b16.5 80 nb cs bolted bonnet flanged end swing check valve as per manufacturing standard bs 1868