A check valve is a mechanical device. It’s type of valve, which normally allows fluid (liquid or gas) to flow through it in only one direction. To prevent the liquid or gas from flowing in the opposite direction (backflow) the check valve closes automatically to prevent this.

Check valves are used in a wide variety of industries;

• oil
• gas
• desalination
• water
• other process industries

The cracking pressure of a check valve is an important concept. This refers to the minimum upstream pressure at which the check valve will operate. During the process of check valve design and check valve manufacture, the valve will given a specific cracking pressure.

A Check Valve can also be known as: clack valve, non-return valve or one-way valve.