A lift check valve is an automatic valve that opens and closes its disc by relying on the flow of the medium itself to prevent medium backflow. It is also known as a non-return valve, one-way valve, reflux valve, or backpressure valve.

As a type of automatic valve, the primary functions of a check valve include preventing medium backflow, avoiding reverse rotation of pumps and their driving motors, and stopping medium leakage from pressure vessels. Check valves can also be installed on supply pipelines for auxiliary systems where internal pressure may rise above the main system pressure.

Check valves are mainly classified into two categories: swing check valves (which rotate around their center of gravity) and lift check valves (which move along the central axis).