This type of valve (also called “equilibrated disc non return valve”) is coupled with on-off valves in high pressure lines to protect the system from the fluid reversing flow, when regular flow is stopped.
The characteristic of this valve is “non slamming”. The disc, with its shape, is maintained in the open position by the fluid flow and its return to closed position does not cause a sudden violent hit against the seat. Design can be to ASME B16.34 but, also, to EN 12516.
Cast body construction and forged body construction are both available. Materials range from carbon steel to low alloy steel (including the widely used modified 9% Cr alloys) to austenitic stainless steels, to nickel alloys. Pressure classes (per ANSI standard) are normally ranging from 600# to 900#, 1500# and 2500#. Size range depends on pressure class requirements, FLUITEK ORSENIGO VALVES having no limits in relation to market requirements.