... source projects, urban water supply and drainage, sewage treatment, electric power, petroleum, petrochemical, heat supply, shipbuilding, medicine and metallurgy industries ... .Suitable Medium:Water, sewage,sea water, air, foodstuff, oil etc.Working Temperature:-10°C~150°COperator:Suitalbe for handles ... GB, ASME, ANSI, API, BS, DIN, JIS etc. warious high quality DN 25 rubber seal butterfly valve