What is the difference between a swing check valve and a lift check valve?
Difference between Swing Check Valve and Lift Check Valve
When choosing a check valve, it is crucial to understand the characteristics of different types of valves. The following are the main differences between swing check valves and lift check valves:
Structure and installation
Swing check valve: The valve disc is disc-shaped and rotates around the rotating axis of the valve seat channel. This design allows the valve disc to rotate freely within 360° and is suitable for horizontal or vertical pipelines.
Lift check valve: The valve disc slides along the vertical center line of the valve body and can only be installed on horizontal pipelines. The lifting and lowering of the valve disc depends on the thrust of the medium and is suitable for high-pressure and small-diameter occasions.
Flow resistance and energy saving
Swing check valve: The flow channel is close to a straight line, which reduces the flow resistance and is suitable for large-diameter occasions, with significant energy-saving effects.
Lift check valve: The channel is an S-shaped bend with a large flow resistance, especially in small diameters.
Sealing and slow closing
Swing check valve: The sealing performance is better, but the slow closing function is less, and a slow closing mechanism is usually required to be installed outside the valve body.
Lift check valve: The valve disc lifting speed can be changed inside the valve body to achieve a slow closing function, which is suitable for occasions that require slow closing.
Applications and standards
Swing check valve: Widely used in various occasions from low pressure to high pressure, in line with multiple international standards, such as GB/T12236, API6D and BS1868.
Lift check valve: Mainly suitable for high pressure and small diameter occasions, the standards are relatively limited.
Comprehensive recommendation
When selecting a check valve, it should be determined according to the specific working pressure, pipeline size and medium characteristics. The swing check valve is particularly suitable for large diameter and high pressure occasions due to its low flow resistance and wide applicability. The lift check valve is more suitable for occasions that require slow closing and specific medium characteristics.