A check valve is a type of valve that is used across a range of different industries and applications. When installed correctly, they provide a vital function to prevent backflow through a system.
The check valve is a simple valve that is designed to work automatically and without the need for electrical power, pneumatic control or human control to turn the valve on and off. Instead, the valve operates by responding to pressure differences on the inlet and outlet side of the valve.
As fluid or gas flows into the inlet side of the valve at a specific pressure range, it pushes the internal disc, gate or other valve component open, allowing the media to flow through the valve. If the pressure drops on the inlet side outside of the pre-configured range, the disc closes, immediately stopping any backward flow.
Essential Considerations
For any type of chemical check valve, the correct pressure differentials for the valve operation is critical. As there is contact between the disc and the sides of the valve, it is important to choose the pressure range correctly to avoid excessive opening and closing of the valve that can lead to early valve failure or poor sealing due to wear and tear on the disc, ball or gate.
Additionally, failing to choose the right pressure for the valve can result in the chemical check valve remaining in a partially open position, which can impact the flow of the system downstream from the valve as well as impact the valve’s performance as it sits in the semi-open position and flutters up and down.
Each of the chemical check valve options should be compared to the pressure rating, but also to the type of media in the system, the position of the valve with regards to installation as well as the line size for the system.