Technical Articles
An Introduction of Swing Check Valves
Posted: 05/23/2017 10:44:18  Hits: 16
Swing check valves have built-in rocker swing structure. All the valves' discs are installed in the valve bodies and can not pierce them. Except that the gaskets and sealing rings are used in the flange part, there is no leakage point on the overall swing check valves, so that can prevent the possibility of valve leakage. The connection between the swing check valves' rockers and clacks adopts a spherical connection structure, making the valves' clacks have freedom in the 360 degree range. Swing check valves are applicable to clean media and should not be used for media containing solid particles or very sticky media.
The structure of swing check valves:
1. Structure: Swing single valve.
2. Drive mode: Butt welding connection.
3. Connection end: Butt welded.
4. The opening and closing of swing check valves are controlled by the pneumatic devices which accelerate the opening and closing speed of valves.
The structural characteristics of swing check valves:
1. Have structures of short length, which is only a fourth of or a eighth of the traditional flanged check valves.
2. Have small size and light weight. The weight is only a fourth or a twentieth of the traditional flanged check valves.
3. The valve clacks can be closed quickly and the surge pressure is small.
4. Can be used for horizontal or vertical pipes and are easy to be installed.
5. Have smooth runners and small resistance of fluid. 
6. Can give sensitive action and have good sealing performance.
7. The valve clacks have short strokes and small impact force when closing the valves.
8. Have overall, simple and compact structures as well as nice shapes.
9. Have long service life and high reliability.
The working principle of swing check valves
The up and down moving of the cylinder plug helps the valve clack quickly open and close so as to reach the sealing surface.
Maintenance of swing check valves:
1. Store the swing check valves in a dry and ventilated room to prevent moisture, rain and rust.
2. Keep the discs closed during transportation and do the following work: the swing check valve clacks should be fixed in the open position; the internal openings of both ends of the full bores should be blocked with foam boards and the ends must be stuffed tightly to prevent the dust and rust as well as to keep the channels clean and the end flat; the cylinder parts should be properly packed to protect them from shake and collision; swing check valves must be placed smoothly as well as steadily and the pneumatic drive devices should be put upwards, not squeezing each other.
3. Every three months, check the swing check valves regularly after their long-term placement. Check if there is any dirt or rust on the two channels as well as sealing surfaces and check the protective condition of the welding end. Wipe the dirt and rust and then repaint the anti-rust oil to protect the channels and the sealing surfaces.