Briefly describe the classification and structure of ball valves

Ball valves are divided into: floating ball valve, fixed ball valve, orbital ball valve, V-shaped ball valve, three-way ball valve, stainless steel ball valve, cast steel ball valve, forged steel ball valve, ash discharge ball valve, anti-sulfur ball valve, pneumatic ball valve, electric ball valve, ferrule Ball valve, welded ball valve.

According to the shell/body material classification, ball valves can be divided into:

1. Metal material valve: such as carbon steel valve, alloy steel valve, stainless steel valve, cast iron valve, titanium alloy valve, Monel valve, copper alloy valve

Doors, aluminum alloy valves, lead alloy valves, etc.

2. Metal valve body lining valves: such as rubber-lined valves, fluorine-lined valves, lead-lined valves, plastic-lined valves, and enamel-lined valves.

3. Non-metallic material valve: such as ceramic valve, glass valve, plastic valve.

There are many domestic manufacturers of ball valves, and most of the connection sizes are not uniform. Mainly divided into the following categories:

The ball of the ball valve is floating. Under the action of the medium pressure, the ball can produce a certain displacement and press tightly on the sealing surface of the outlet end to ensure the sealing of the outlet end.

The structure of the ball valve:

The sealing performance is good, but the load of the sphere bearing the working medium is all transferred to the outlet sealing ring. Therefore, it is necessary to consider whether the material of the sealing ring can withstand the working load of the sphere medium. When subjected to high pressure shock, the sphere may shift. . This structure is generally used for medium and low pressure ball valves.

The ball of the ball valve is fixed and does not move under pressure. The fixed ball valve has a floating valve seat. After being pressurized by the medium, the valve seat moves, so that the sealing ring is tightly pressed on the ball to ensure the sealing. Bearings are usually installed on the upper and lower shafts with the ball, and the operating torque is small, which is suitable for high-pressure and large-diameter valves.

In order to reduce the operating torque of the ball valve and increase the reliability of the seal, oil-sealed ball valves have appeared, which not only inject special lubricating oil between the sealing surfaces to form an oil film, which not only enhances the sealing performance, but also reduces the operating torque. Suitable for high pressure and large diameter ball valves.