Spherical stainless steel check valve standards and norms Spherical stainless steel check valve, also known as check valve, its role is to prevent the media back in the pipeline. Opening and closing parts by the media flow and strength to open or close their own to prevent the media back to the valve called stainless steel check valve. Stainless steel check valve is an automatic valve, mainly used for medium one-way flow of the pipeline, only to allow medium to flow in one direction to prevent accidents. Ball Type Stainless Steel Check Valve Standard and Specification 1. Design and Manufacture: API594, API6D, JB / T8937 2. Structure Length: API594, API6D, DIN3202, JB / T8937 3. Pressure and Temperature Rating: SNSIB16.34, DIN2401, GB / T9124, HG20604, HG20625, SH3406, JB / T74 4, Test and inspection: API598, JB / T9092 5, Pipe flange: JB / T74 ~ 90, GB / T9112! 9124, HG20592 ~ 20635, SH3406, ANSIB16.5 , DIN2543 ~ 2548, GB / T13402, API605, ASMEB16.47