... valves,ball valves,butterfly valves,diaphragm valves,mud valve ect.And it has complete inspection equipment, such ... , DIN 3230, JIS B2003, API5983) Face to face dimensions: BS5163: 1986, DIN 3202 F4-F5, JIS B2002, ... The surface and the adjusting media of the valve shaft are nitrogenized so that it is erosion ... There is no backward sealing structure in the valve, so the sealing id reliable.5.The material ...