... and chemical resistance b.High temperature resistance c. Excellent weather and water resistance Double Flange Butterfly Valve: SizeDN40 - DN1400Design StandardAPI ... Suitalbe for handles(dn50~300), gear operators, electric and pneumatic control actrators.Products;We can produce butterfly valves, check valves ... GB, ASME, ANSI, API, BS, DIN, JIS etc. various high quality Double Flange Butterfly valve