... DI,WCB,Stainless Steel disc-D Double Flange Butterfly Valve:SizeDN40 - DN1200Design StandardAPI 609End flangeEN1092 ,ANSI 125 ... urban water supply and drainage, sewage treatment, electric power, petroleum, petrochemical, heat supply, shipbuilding, medicine and metallurgy industries. ... and manufactured in accordance with the standards of GB, ASME, ANSI, API, BS, DIN Double flange DN1200 Butterfly valve ...