Types and Advantages of Ball Valves

The ball valve is mainly used in the pipeline to cut off, distribute and change the flow direction of the medium. The ball valve and the plug valve are the same types of valve, only its closing part is a ball, and the ball rotates around the centerline of the valve body to achieve opening and closing. The ball valve is a new type of valve widely used in recent years, it has the following advantages, an industrial globe valve supplier for you to introduce.

1. The fluid resistance is small, and the resistance coefficient is equal to that of the pipe section of the same length.

2. Simple structure, small size, and lightweight.

3. It is tight and reliable. At present, the sealing surface material of the ball valve is widely used plastic and has good sealing performance. It has also been widely used in the vacuum system.

4. It is easy to operate and quick to open and close. It only needs to rotate 90° from fully open to fully closed to facilitate remote control.

5. The maintenance is convenient, the structure of the ball valve is simple, the sealing ring is generally movable, and the disassembly and replacement are more convenient.

6. When fully open or fully closed, the sealing surfaces of the ball and the valve seat are isolated from the medium. When the medium passes through, it will not cause corrosion of the valve sealing surface.

7. It has a wide range of applications, from small diameters to a few millimeters to a few meters, from high vacuum to high pressure. Ball valves have been widely used in petroleum, chemical, power generation, papermaking, atomic energy, aviation, rockets, and other departments, as well as people's daily lives.

ANSI Floating Ball Valve

The ball valve can be divided according to the structure:

1. ANSI Floating Ball Valve

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 floating ball valve is simple and the sealing is good, but the load of the ball bearing the working medium is all transferred to the outlet sealing ring, so it is necessary to consider whether the sealing ring material can withstand the working load of the ball medium. This structure is widely used in low-pressure ball valves.

2. Fixed ball valve

The ball of the ball valve is fixed and does not move after being pressed. Fixed ball valves are equipped with floating seats. After being pressurized by the medium, the seats move, so that the sealing ring is pressed tightly on the ball to ensure sealing. Usually, bearings are installed on the upper and lower shafts of the sphere, the operation torque is small, and it 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 in recent years. Both special injections of lubricating oil are injected between the sealing surfaces to form a layer of oil film, which enhances the sealability and reduces the operating torque. , More suitable for high-pressure large-caliber ball valves.

3. Elastic ball valve

The ball of the ball valve is elastic. Both the ball and the seat sealing ring are made of metal materials, and the specific pressure of the seal is very large. The pressure of the medium itself can not meet the requirements of the seal, and an external force must be applied. This valve is suitable for high temperature and high-pressure media. The elastic sphere is formed with an elastic groove at the lower end of the inner wall of the sphere to obtain elasticity. When closing the channel, the wedge-shaped head of the valve stem is used to expand the ball and compress the valve seat to achieve a seal. Loosen the wedge head before turning the ball, and the ball will return to its original shape, resulting in a small gap between the ball and the valve seat, which can reduce the friction and operating torque of the sealing surface. The ball valve can be divided into straight type, three type and right angle type according to its channel position. The latter two types of ball valves are used to distribute the medium and change the flow of the medium.