ÖNORM EN 16767

This European Standard specifies the requirements for cast iron or steel check valves, which are forged, cast or fabricated in straight, angle or oblique pattern (see EN 736-2) with end connections flanged or wafer, butt welding, socket welding, or threaded. This European Standard applies to check valves mainly used for industrial and general purpose applications. However, they may be used for other applications provided the requirements of the relevant performance standards are met. Back flow prevention anti-pollution check valves are outside the scope of this European standard. The range of nominal sizes covered is: DN 8, DN 10; DN 12, DN 15; DN 20; DN 25; DN 32; DN 40; DN 50; DN 65; DN 80; DN 100; DN 125; DN 150; DN 200; DN 250; DN 300; DN 350; DN 400; DN 450; DN 500; DN 600; DN 700; DN 750; DN 800; DN 900; DN 1 000. DN 8 and DN 12 are not used for PN designated flanged end connections. DN 8, DN 10 and DN 12 are not used for Class designated flanged end connections. DN 750 is used for Class designated valves only. Socket welding end valves and threaded end valves are limited to the range DN 8 to DN 65. The range of pressure designations covered is: a) for flanged end and wafer type end cast iron bodies: - PN 2,5; PN 6; PN 10; PN 16; PN 25; - Class 125; Class 250; b) for flanged end, wafer type and butt welding end steel bodies: - PN 40; PN 63; PN 100; - Class 150; Class 300; Class 600; c) for socket welding end and threaded end steel bodies: - PN 40; PN 63; PN 100; - Class 600; Class 800.