Thread check valve, thread check valve H12/H14

Check valve function The check valve is an automatic valve. Its main function is to prevent the backflow of the medium, prevent the pump and drive motor from reversing, and release the container medium. Check valves may also be used on lines supplying auxiliary systems where the pressure may rise above the system pressure.
Classification of check valves
Check valves can be divided according to their structure and installation method
Swing check valve The valve disc of the swing check valve is disc-shaped and wraps around The rotating shaft of the valve seat channel rotates. Because the channel in the valve is streamlined, the flow resistance is smaller than that of the lift check valve. It is suitable for low flow rates and large diameter situations where the flow does not change frequently. However, it is not suitable for pulsating flow. The sealing performance is not as good as that of the lifting type. Swing check valves are divided into three types: single-disc type, double-disc type and multi-half type. These three forms are mainly divided according to the valve diameter. The purpose is to prevent the medium from stopping the flow or backflow and weakening the hydraulic impact.
Two lift check valves are check valves in which the valve disc slides along the vertical centerline of the valve body. The lift check valve can only be installed on horizontal pipelines. The valve disc can be used on high-pressure small-diameter check valves. round ball. The valve body shape of the lift check valve is the same as that of the stop valve (it can be used universally with the stop valve, so its fluid resistance coefficient is large. Its structure is similar to that of the stop valve, and the valve body and valve disc are the same as the stop valve. The upper part of the valve disc and the valve The lower part of the cover is processed with a guide sleeve. The valve disc guide can be lifted and lowered freely in the valve guide. When the medium flows forward, the valve disc is opened by the thrust of the medium. When the medium stops flowing, the valve disc falls on the valve seat by self-extension. On the vertical lift check valve, the direction of the medium inlet and outlet channels is the same as the direction of the valve seat channel, and its flow resistance is relatively small. The straight-through type is small.
Three-disc check valve is a check valve in which the disc rotates around the pin in the valve seat. The disc check valve has a simple structure and can only be installed on horizontal pipes, so its sealing performance is poor.
The four-pipe check valve is a valve whose disc slides along the center line of the valve body. The pipe check valve is a new type of valve. It is small in size, light in weight, and has good processing technology. One of the development directions of check valves. However, the fluid resistance coefficient is slightly larger than that of the swing check valve.
The five-pressure check valve is used as a boiler feed water and steam cut-off valve. It has a lift The comprehensive function of check valve and globe valve or angle valve.