The characteristics of the ball valve

The characteristics of the ball valve

The ball valve came out in the 1950s. With the rapid development of science and technology, the continuous improvement of production technology and product structure, it has rapidly developed into a major valve category in just 40 years. In western industrially developed countries, the use of ball valves is increasing year by year.

In my country, ball valves are widely used in petroleum refining, long-distance pipelines, chemical industry, papermaking, pharmaceuticals, water conservancy, electric power, municipal, steel and other industries, and occupy a pivotal position in the national economy. It has the action of rotating 90 degrees. The cock body is a sphere with a circular through hole or channel passing through its axis.

The ball valve is mainly used to cut off, distribute and change the flow direction of the medium in the pipeline. It only needs to be rotated 90 degrees and a small rotational torque can be closed tightly. Ball valves are most suitable for on-off and shut-off valves, V-type ball valves. In addition to paying attention to the pipeline parameters, the electric valve should also pay special attention to the environmental conditions of its use. Since the electric device in the electric valve is an electromechanical device, its use status is greatly affected by its use environment. Under normal conditions, special attention should be paid to the use of electric ball valves and butterfly valves in the following environments

The characteristics of the ball valve

1. Wear-resistant; since the spool of the hard-sealed ball valve is spray-welded with alloy steel,
The sealing ring is alloy steel surfacing, so the hard-sealed ball valve will not produce too much wear when switching. (It has a hardness factor of 65-70):

2. The sealing performance is good; since the sealing of the hard-sealed ball valve is manually ground, it cannot be used until the valve core and the sealing ring are completely matched. So his sealing performance is reliable.

3. The switch is light; since the bottom of the sealing ring of the hard-sealed ball valve adopts a spring to tightly hug the sealing ring and the valve core, the switch is very light when the external force exceeds the pre-tightening force of the spring.

4. Long service life: It has been widely used in petroleum, chemical industry, power generation, papermaking, atomic energy, aviation, rocket and other departments, as well as in people's daily life. Pneumatic ball valve has simple and compact structure, reliable sealing, and convenient maintenance. The sealing surface and spherical surface are always in a closed state, which is not easy to be eroded by the medium, and is easy to operate and maintain. It is suitable for general working media such as water, solvent, acid and natural gas, and is mainly used for cutting off Or connect the medium in the pipeline, and can also be used for fluid regulation and control.

Compared with other types of valves, the pneumatic ball valve has angular stroke output torque, fast opening, stable and reliable, wide application, and the following advantages:
1. The thrust bearing reduces the frictional moment of the valve stem, which can make the valve stem operate smoothly and flexibly for a long time.
2. Anti-static function: a spring is set between the ball, valve stem and valve body, which can discharge the static electricity generated during the switching process.
3. Due to the good self-lubricating properties of polytetrafluoroethylene and other materials, the friction loss with the ball is small, so the service life of the pneumatic ball valve is long.
4. Small fluid resistance: Pneumatic ball valve is the one with the smallest fluid resistance in all valve classifications. Even for reduced diameter pneumatic ball valves, its fluid resistance is quite small.

5. Reliable sealing of the valve stem: Since the valve stem only rotates and does not move up and down, the packing seal of the valve stem is not easy to be damaged, and the sealing capacity increases with the increase of the medium pressure.
6. The sealing performance of the valve seat is good: the sealing ring made of elastic material such as polytetrafluoroethylene is easy to seal, and the valve sealing capacity of the pneumatic ball valve increases with the increase of the medium pressure.
7. The fluid resistance is small, and the full-bore ball valve basically has no flow resistance.
8. Simple structure, small size and light weight.
9. Tight and reliable. It has two sealing surfaces, and the sealing surface materials of the ball valve are widely used in various plastics, which have good sealing performance and can achieve complete sealing. It has also been widely used in vacuum systems.

10. It is easy to operate and open and close quickly. It only needs to rotate 90° from fully open to fully closed, which is convenient for long-distance control.
11. The maintenance is convenient, the structure of the ball valve is simple, the sealing ring is generally movable, and it is convenient to disassemble and replace.
12. When fully open or fully closed, the sealing surface of the ball and the valve seat is isolated from the medium. When the medium passes through, it will not cause erosion of the valve sealing surface.
13. It has a wide range of applications, with a diameter ranging from a few millimeters to a few meters, and can be applied from high vacuum to high pressure.
14. Since the ball valve has wiping properties during the opening and closing process, it can be used in the medium with suspended solid particles.

15. The processing precision is high, the cost is expensive, and it is not suitable for use in high temperature. If there are impurities in the pipeline, it is easy to be blocked by impurities, causing the valve to fail to open.