Check valves are two-port valves, meaning they have two openings in the body, one for fluid to enter and the other for fluid to leave. There are various types of check valves used in a wide variety of applications. Check valves are often part of common household items. Although they are available in a wide range of sizes and costs, check valves generally are very small, simple, or inexpensive. Check valves work automatically and most are not controlled by a person or any external control; accordingly, most do not have any valve handle or stem. The bodies (external shells) of most check valves are made of plastic or metal.
An important concept in check valves is the cracking pressure which is the minimum upstream pressure at which the valve will operate. Typically the check valve is designed for and can therefore be specified for a specific cracking pressure.
1.5" - 48"（DN40 - DN1200）
150LB - 1500LB (PN16 - PN420)
-196℃ - 560℃
Socket welding or inner screwed
Full bore or reduced bore, B.B or W.B or pressure seal bonnet, through way, OS&Y
Oil and gas pipeline
Main Parameter Specification
Inspection and test: API598, JB/T9092;
Design and manufacture: API594, API 6D, JB/TB8937;
Face to face and end to end: API594, API6D, DIN3202, JB/T8937;
Pressure-temperature rating: ASME B16.34, DIN2410, GB/T9124, HG20625, SH3406, JB/T74.