1. The valve flap of the high-pressure check valve has a disc shape and rotates around the rotation shaft of the valve seat passage. Since the valve passage is streamlined, the flow resistance is smaller than that of the butterfly butterfly check valve, and is suitable for low flow rate and flow. Large-caliber occasions that do not change frequently, but not suitable for pulsating flow, high-pressure check valves are not as good as lift-type check valves. The butterfly check valve is divided into three types: single-valve, double-valve and multi-half. These three forms are mainly divided according to the valve diameter. The purpose is to prevent the hydraulic shock from being weakened when the medium stops flowing or reverses.

2. The high-pressure check valve slides along the vertical centerline of the valve body. The internal thread check valve can only be installed on the horizontal pipe. On the high-pressure small-diameter check valve, the valve ball can be used. The shape of the butterfly check valve (butterfly check valve) is the same as that of the shut-off valve (common to the shut-off valve), so its fluid resistance coefficient is large. The high pressure check valve structure is similar to the shutoff valve, and the valve body and the disc are the same as the shutoff valve. The upper part of the valve flap and the lower part of the valve cover are machined with a guide sleeve, and the valve guide can be easily lifted and lowered in the valve guide guide. When the medium is downstream, the valve flap is opened by the medium thrust. When the medium stops flowing, the valve flap is self-retained. The drooping falls on the valve seat to prevent the medium from flowing back. The direction of the inlet and outlet passages of the straight-through butterfly check valve is perpendicular to the direction of the valve seat passage; the vertical lift check valve has the same direction of the medium inlet and outlet passages as the valve seat passage, and its flow resistance is smaller than that of the straight-through type.
3. The high pressure check valve is a check valve that rotates the valve disc around the pin shaft in the valve seat. The disc type check valve has a simple structure and can only be installed on a horizontal pipe, and has good sealing performance.
4. The high pressure check valve is a valve that slides along the centerline of the valve body. Pipeline check valve is a new type of valve. It is small in size, light in weight and good in processability. It is one of the development directions of check valves. However, the fluid resistance coefficient is slightly larger than the swing check valve.
5. High-pressure check valve is a valve for boiler feed water and steam shut-off. It has the comprehensive function of lift check valve and stop valve or angle valve.
In addition, there are some check valves that are not suitable for pump outlet installation, such as bottom valves, spring-type check valves, Y-type check valves, etc.