... CE Certificate 3,double disc 4,do OEM Double Disc Check Valve Technical Date:Nominal Diameter:DN50-DN700Nominal Pressure:PN10/PN16Operation Temperature ... Medium:Water,Sewage,Seawater,Gas,Food,Oils,etc.Double Disc Check Valve Standard:Design Standard:JB/T8527-97Structural Length:GB/T12221-1989 ... to face dimensions:GB/T17241.6Type of connection:Double disc check valve