1). Swing Check Valve

Working principle

The medium pushes the valve disc to rotate and open. When the medium flows back, the valve disc automatically closes by its own gravity or reverse fluid pressure.

Features
Low fluid resistance: Since the disc rotates to open and close, the fluid resistance when the medium passes through is small, which is suitable for low-pressure systems with large flow rates.

Suitable for large-diameter pipelines: This valve is usually used in large-diameter pipelines because its design adapts to the flow of fluids with larger flow rates. The water hammer effect may be strong: Since the disc closes slowly, a water hammer effect (i.e., the pressure wave generated by the rapid impact of the reverse fluid on the valve) may occur when it is suddenly closed, and additional design measures are required to reduce the risk of water hammer.

Flexible installation: The swing check valve can be installed horizontally or vertically (the medium flows from bottom to top), and has a wide range of adaptability.

Easy maintenance: The structure is simple, and the design of the disc and hinge makes it easier to inspect and maintain. The disc usually wears slowly, but the sealing of the disc and the valve seat needs to be checked regularly.

2). Lift Check Valve
Working principle

When the medium flows downstream, the medium pressure pushes the valve disc up and the fluid passes through;

when the medium flows in the reverse direction, the valve disc closes quickly under gravity and fluid pressure.

Features

Good sealing: Since the valve disc moves up and down, it is in close contact with the valve seat and has a good sealing effect, which is suitable for systems requiring high sealing.
Large fluid resistance: The fluid needs to push the valve disc up, so compared with other types of check valves, the flow resistance is larger, which is suitable for systems with higher flow rates.
Suitable for small-diameter, high-pressure systems: Lift check valves are usually used for small-diameter pipes, especially in high-pressure environments.
Can only be used for horizontal or vertical pipes: When used for horizontal pipes, the fluid direction must be consistent with the valve seat to ensure that the valve disc can rise and fall normally.
Simple maintenance: The structure is simpler and easy to disassemble and repair, but the wear of the valve disc and valve seat needs to be checked regularly.

3).Wafer Check Valve

Working principle

The valve disc of the wafer check valve is usually two semicircular ones, similar to butterfly wings, and the valve is clamped between two flanges during installation.
When the medium flows forward, the fluid pressure pushes the valve disc open to allow the fluid to pass.
When the medium flows back, the valve disc automatically closes under the action of the spring or fluid pressure to prevent the medium from flowing back.

Features

Compact structure: short valve length, suitable for places with limited space.
Lightweight: lighter than other check valves, easier to install.
Easy to install: clamped between flanges, no additional support required.
Double flap design: fast closing under low pressure to prevent water hammer.
Wide application: can be used in horizontal or vertical pipelines, suitable for large flow, low pressure systems.

4). Tilted disc check valve

Working principle

The tilted design of the valve disc reduces the impact of the fluid on the valve, and the closing process is relatively gentle, reducing the water hammer phenomenon.
When the medium flows downstream, the fluid pressure pushes the valve disc to rotate around its hinge, the valve opens, and the fluid passes smoothly.
When the medium flows backward, the fluid pressure tilts the valve disc to the closed position, and the valve disc fits tightly against the valve seat to prevent the medium from flowing back.

Features

Small fluid resistance: The tilted design of the valve disc makes the medium flow more smoothly when passing through, reducing fluid resistance.
Good anti-water hammer effect: The closing process is smooth, reducing the risk of water hammer.
Flexible installation: It can be used for horizontal and vertical pipelines and has strong adaptability.
Simple structure: The design is simple and maintenance is convenient. Usually, you only need to check the wear of the valve disc and valve seat regularly.
Good sealing performance: The valve disc fits tightly with the valve seat to ensure good sealing and prevent medium leakage.

5). Quickly close the extraction steam check valve

Working principle

During normal operation: the valve remains closed, the fluid passes through the system normally, and the valve does not interfere with the flow of the medium.
When the system has backflow or negative pressure: the valve will open quickly to allow external air or medium to enter the system, thereby destroying the negative pressure and preventing vacuum formation or medium backflow.
Valve closing process: After the forward flow of the medium is restored, the valve closes quickly under the action of the spring or fluid pressure to prevent external air or medium from continuing to enter the system.

Features

Quick response: Open or close quickly to prevent system damage due to negative pressure or backflow.
Prevent negative pressure: When negative pressure occurs, the valve opens quickly to prevent vacuum formation.
Prevent backflow: The valve closes quickly during backflow to avoid damage to equipment.
Reduce water hammer: The quick closing design reduces reverse fluid impact.
Simple and reliable structure: Spring, gravity or fluid pressure control, low failure rate.
Flexible installation: Suitable for horizontal or vertical piping systems.