... .Ozone and chemical resistance b.High temperature resistance c. Excellent weather and water resistance Double Flange Butterfly Valve: SizeDN40 - DN1400Design StandardAPI ... operators, electric and pneumatic control actrators.Products;We can produce butterfly valves, check valves, gate valves and so on with ... of GB, ASME, ANSI, API, BS, DIN, JIS etc. various high quality Double Flange Butterfly valve