cast iron flanged DIN check valve. DN40-DN300MM with the best quality

1.It's ball type check valve. 

2 Either too low a line velocity or too high a velocity can damage valve internals and shorten valve life.

3.Service in systems involving rapid and frequent flow reversals, pulsation or excessively turbulent flow should be avoided.

4Threaded seat rings in valves in services with high velocity (turbulent) flow or thermal cycling should be lock welded to the body to avoid loosening.