Time：2021-03-17 13:16 Browse：
（1）、Swing check valve: swing check valve disc is disk shape, rotating around the seat channel shaft rotation movement, because the valve inside the channel into a streamlined, flow resistance than the lifting check valve is small, suitable for low velocity and flow is not often changed in the large-bore occasions, but not suitable for pulsating flow, its sealing performance is less than the lifting. Swing type check valve is divided into single valve, double valve and more than three types, the three forms mainly according to the valve diameter to divide, the purpose is to prevent the medium to stop the flow or reverse flow, weaken the hydraulic impact.
（2）、Lift check: a check valve with a disc sliding along the vertical center line of the valve body. The lift check valve can only be installed in horizontal lines. The disc can be used as a ball on the high-pressure small-bore check valve. Elevating check valves have the same body shape as globe valves (which can be used as globe valves) and therefore have a greater coefficient of fluid resistance. Its structure is similar to the globe valve, valve body and disc and globe valve phase.
（3）、Mute check valve is the same. The upper part of the disc and the lower part of the cover are processed with guide sleeve, the valve disc guide can be in the valve head guide Jane free rise and fall, when the medium flow, the disc by the medium thrust open, when the medium stopped flow, the disc by the vertical landing on the seat, to prevent the adverse flow of the medium. Straight through lift check valve medium inlet and outlet channel direction and seat channel direction vertical; Vertical lift check valve, the direction of the medium inlet and outlet channel and the valve seat channel direction, the flow resistance is smaller than straight.
（4）、Disc check: a check valve in which the disc rotates around a pin in the seat. Disc check valve is simple in structure, can only be installed in the horizontal pipeline, poor sealing.
（5）、Pipe check: a valve with disc sliding along the center line of the body. The pipe type check valve is a kind of newly appeared valve, its volume is small, the weight is lighter, the processing technology is good, is one of the development direction of the check valve. But the fluid resistance coefficient is slightly larger than the swing check valve.
（6）、Pressure check valve: this valve is used as a boiler feed and steam cut-off valve, it has the function of lifting check valve and globe or Angle valve.
In addition, some are not suitable for pump outlet installation check valve, such as bottom valve, spring, Y, etc.
Matters needing attention
1、Do not allow the check valve to bear weight in the piping system. Large check valves should be supported independently from the pressure generated by the piping system.
2、Note that the direction of media flow should be consistent with the direction of arrow marked by the valve body.
3、Elevating vertical disc check valve shall be installed in vertical pipeline.
4、Elevating horizontal disc check valve shall be installed in the horizontal pipeline.