A check valve, also known as a one-way valve or non-return valve, is a valve that prevents the backflow of media. They are widely used in piping systems to ensure that fluid can only flow in one direction. Here are seven common types of check valves:
- Swing Check Valve:
The disc of this check valve rotates around the pin to open and close. In the fully open state, the fluid pressure is almost unimpeded, so the pressure drop through the valve is relatively small. Swing check valves are suitable for larger diameters, higher pressures (can also be used in vacuum systems) and larger flows.
- Lift Check Valve:
The disc of this check valve slides along the vertical centerline of the valve body. Lift check valves can only be installed on horizontal pipes, and the disc on high-pressure small-diameter check valves can be made of spherical balls. The body shape of the lift check valve is the same as that of the stop valve (which can be used with the stop valve), so its fluid resistance coefficient is larger.
- Wafer Check Valve:
Wafer Check Valve is usually installed between two flanges and fixed by bolts. It has a compact structure and is easy to install. This check valve is usually used in small and medium-sized pipeline systems.
- Silent Check Valve:
Silent Check Valve is designed to reduce the noise generated when fluid flows back. This valve is usually used in places where a quiet environment is required, such as hospitals, schools, etc.
- Butterfly Check Valve:
The disc shape of the butterfly check valve is similar to that of the butterfly valve, and it is usually installed on horizontal pipes. It has a simple structure and low fluid resistance, but the sealing performance may be relatively weak.
- Ball Check Valve:
The disc of the ball check valve is a sphere or hemisphere, which is opened or closed by the force of the medium. This valve is usually used in small-diameter pipes, such as household or small industrial applications.
- Slow-Closing Check Valve:
The slow-closing check valve has a delay feature during the closing process, which can reduce the occurrence of water hammer. This valve is often used in systems that need to control fluid impact.
