What is a Lift Check Valve ?
A lift check valve is self actuated one-way valve (NRV-non-return valve) which allows flow of fluid in one direction through lift of valve disc. Lift type check valve is commonly used in piping systems in which globe valves are being used as a flow control valve. They have similar seating arrangements as globe valves. Lift check valves are suitable for installation in horizontal or vertical lines with upward flow.
Lift type Check Valve How it Works?
Construction of lift check valve is similar to globe type valve. As the flow enters, the disk or ball is raised within guides from the seat by the pressure of the upward flow. When the flow stops or reverses, the disk or ball is forced onto the seat of the valve by both the backflow and gravity.Lift type check valves are available in three body patterns: horizontal, angle, and vertical.
Point to remember: Flow to lift check valves must always enter below the seat.
Applications of Lift Check Valves
They are recommended for use with steam, air, gas, water, and on vapor lines with high flow velocities. Some types of lift check valves may be installed horizontally. In this design, the ball is suspended by a system of guide ribs. This type of check valve design is generally employed in plastic check valves.