1. The valve flap of the low temperature check valve is disc-shaped, and rotates around the rotation axis of the valve seat channel. Because the channel inside the valve is streamlined, the flow resistance is smaller than that of the butterfly check valve, which is suitable for low flow rates and irregular flow. Changing large-caliber occasions, but it is not suitable for pulsating flow, and its sealing performance is not as good as that of lifting type. The butterfly check valve is divided into three types: single, double and multiple. The three types are mainly divided by the valve diameter. The purpose is to prevent the hydraulic shock when the medium stops flowing or flows backward.
2. The low temperature check valve flap is a check valve that slides along the vertical centerline of the valve body. The internally threaded check valve can only be installed on horizontal pipelines. On high pressure small diameter check valves, the valve disc can be a ball. The body shape of butterfly check valve is the same as that of globe valve (can be used with globe valve), so its fluid resistance coefficient is large. Its structure is similar to a globe valve, with the same body and disc as the globe valve. The upper part of the valve disc and the lower part of the valve cover are processed with a guide sleeve. The valve disc guide can be freely raised and lowered in the valve guide. When the medium flows, the valve disc is opened by the thrust of the medium. Falling down on the valve seat, it plays a role in preventing the medium from flowing backward. The direction of the medium inlet and outlet channels of the straight-through butterfly check valve is perpendicular to the direction of the valve seat channel; the vertical lift check valve has the same direction of medium inlet and outlet channels as the valve seat channel, and its flow resistance is smaller than that of the straight type.
3. Low temperature check valve: a check valve whose valve disc rotates around a pin in the valve seat. The disc check valve has a simple structure and can only be installed on horizontal pipelines, and has good sealing performance.
4. Low-temperature check valve: a valve whose valve disc slides along the center line of the valve body. Pipeline check valve is a new type of valve. Its small size, light weight, and good processing technology are one of the development directions of check valves. However, the coefficient of fluid resistance is slightly larger than that of the swing check valve.
5, compact check valve: This valve is used as a boiler feed water and steam shutoff valve, it has the integrated function of lifting check valve and globe valve or angle valve.
In addition, there are some check valves that are not suitable for the pump outlet installation, such as foot valve, spring type, Y type and other check valves.
The valve is used as a device for preventing the medium from flowing backward on industrial pipelines.
Notes When Use
1 . It should ensure that the pipe is blown clean before installation.
2 . When installing, make sure that the flow direction indicated by the arrow on the valve body should be consistent with the flow direction of the fluid.
3 . This valve has been degreased. Store and keep clean when installing.
4 . After the pipeline construction is completed, all the valves on the pipeline should be opened, and the residue in the pipeline should be thoroughly and thoroughly kept to ensure that the pipeline system is clean and free of debris.
5 . The installation system diagram with the oil-free requirements should be degreased.
6 . Slowly open and close during use.
7 . If the precision parts such as the valve disc, valve seat and valve stem are worn or damaged, it must be repaired and replaced in time.
8 . For parts such as gaskets and sealing materials, replace them with new ones each time.
