Ball valve came out in the 1950s, with the rapid development of science and technology, production technology and product structure of continuous improvement, in a short period of 40 years, has rapidly developed into a major valve class. In Western developed countries, the use of ball valves is increasing year by year.
In China, the ball valve is widely used in petroleum refining, long-distance pipeline, chemical, paper, pharmaceutical, water, electricity, municipal, steel and other industries, occupies a pivotal position in the national economy. It has a 90 degree rotation action, the swivel body is a sphere, with a circular through hole or passage through its axis.
The ball valve is mainly used in the pipeline to cut, distribute and change the direction of flow of the media, it only needs to rotate 90 degrees of operation and a small turning torque can be closed tight. Ball valve is most suitable for the switch, cut off the valve to use, V-type ball valve. Electric valve should pay attention to the pipeline parameters, the special attention should be paid to the use of environmental conditions, because the electric valve in the electric device is a mechanical and electrical equipment, its use of its use by the environment greatly affected. Normally, the electric ball valve, butterfly valve in the following environment to pay special attention.
One; wear; as a result of hard seal ball valve is alloy steel spray welding,
The sealing ring is alloy steel surfacing, so the hard seal ball valve in the switch will not produce too much wear. (Its hardness factor is 65-70):
Two; sealing performance; due to the seal of the hard seal ball valve is used artificial grinding, until the spool and seal ring can be used in order to fully use. So his sealing performance is reliable.
Three; switch light; as a result of hard seal ball valve ring at the bottom of the spring so that the seal ring and the spool firmly together, so the outside force exceeds the spring preload when the switch is very light.
Four; long life: has been widely used in petroleum, chemical, power generation, paper, atomic energy, aviation, rockets and other departments, as well as people's daily lives.
Pneumatic ball valve compact structure, reliable sealing, simple structure, easy maintenance, sealing surface and the spherical surface is often closed, not easily eroded by the media, easy to operate and maintenance, for water, solvents, acids and natural gas and other general working medium, In the cut-off or connected to the pipeline in the medium, can also be used for fluid regulation and control.
Pneumatic ball valve compared with other types of valves, with angular travel output torque, open quickly, stable and reliable, widely applicable, and so the following advantages.
1, thrust bearing to reduce the stem friction torque, the stem can be long-term operation smooth and flexible.
2, anti-static function: in the sphere, stem, valve body set between the spring, the switch can produce static electricity derived.
3, due to PTFE and other materials with good self-lubricating, and the ball friction loss is small, so the use of pneumatic ball valve long life.
4, the fluid resistance is small: Pneumatic ball valve is the valve in all the classification of the smallest resistance to a fluid, even the reduced diameter pneumatic ball valve, the fluid resistance is also quite small.
5, the stem seal is reliable: the stem as only imitation and movement without lifting movements, stem packing seal is not easy to damage, and the sealing capacity increases with the pressure of the media increases.
6, the valve seat sealing performance: the use of PTFE and other elastic materials made of seals, the structure is easy to seal, and pneumatic valve valve sealing capacity increases with the media pressure increases.