Check valves are used to prevent the reversal of the flow in a fast and automatic way. It permits the flow in one direction and prevents it from flowing in the opposite direction. It is used to block the flow and not to control it. It uses the energy of the proper flow so that its operational cycle occurs, therefore it does not need human force nor from another external action to function. Very trustworthy to use in vapor, air, coal gas or oil gas at high or low temperatures.
Normally for low or medium pressure, the valve adopts a verc to reduce the internal leakage of the type. It can be equipped with an external lever and possibility to adjust the weight of the casting and select the type of connection and trim material according to the working condition if the user needs. The check valve is usually equipped with a vibration drum.