What is one way valve? 

One way valve is one kind of check valve where the fluid can only flow along the inlet, but the medium at the outlet cannot flow back, which is why that valve is called one-way valve. One way valve is also known as check valve, non return valve, cut off valve. One way valve is used in hydraulic system to prevent reverse flow of oil flow, or used in pneumatic systems to prevent reverse flow of compressed air. One way valve can be divided into two types: straight through one way valve, and right angle one way valve. The straight through one way valve is installed on the pipeline with threaded connection. Right angle one way valve has three connect types: threaded connection, plate connection, flange connection. 

One way check valve is one kind of check valve, is usually installed in horizontal pipelines, can also be installed in vertical and oblique pipelines. 

When installing the one way valve, special attention should be paid to the flow direction of the medium, and the normal flow direction of the medium should be consistent with the direction of the flow arrow indicated on the valve body, otherwise, the normal flow of medium will be cut off. The foot valve should be installed at the bottom of the suction pipelines of the water pump. 

When the check valve is closing, water hammering pressure will be generated in pipeline, which will cause damage to the valve, pipeline or equipment in severe cases, especially for large diameter pipelines and high pressure pipelines, so the check valve user should pay more attention on that.