How should Different Industries Choose Ball Valves?
Ball valves came out in the 1950s. With the rapid development of science and technology and the continuous improvement of the production process and product structure, the ball valve has rapidly developed into a major type of valve in a short period of 50 years. In the western industrialized country, the use of a ball valve is rising year by year.
The ball valve is mainly used in the pipeline to cut off, distribute and change the flow direction of the medium. It only needs to be operated with a rotation of 90 degrees and a small rotation moment to close tightly. Ball valves are best used as switches and shutoff valves.
Since ball valves are usually made of rubber, nylon, and polytetrafluoroethylene as seat sealing materials, their usage temperature is limited by seat sealing materials. The cutoff of the ball valve is achieved by the metal ball in the role of medium, between plastic seats to press each other (floating ball valve). The local area of the seat sealing ring will undergo elastoplastic deformation under certain contact pressure, which can compensate the manufacturing precision and surface roughness of the ball and ensure the sealing performance of the ball valve.
The seat sealing ring of the ball valve is usually made of plastics, so the fire resistance and fire prevention of ball valve should be considered in the choice of the structure and performance of ball valve, especially in petroleum, chemical, metallurgy, and other departments, inflammable and explosive medium equipment and pipeline system.
Ball valve has many kinds, such as floating ball valve, fixed ball valve, trackball valve, V ball valve, three-way ball valve, sanitary ball valve, stainless steel ball valve, floating ball valve, cast steel ball valve, forging steel ball valve, ash ball valve, sulfur resistance ball valve, sleeve ball valve, welding ball valve.
Generally, ball valves are recommended in pipeline systems with double regulation, strict sealing performance, constriction channels, quick opening and closing, low noise, cavitation and gasification, minor leakage to the atmosphere, small operating torque and small fluid resistance. Besides, the ball valve is also suitable for the piping system with light structure, low-pressure cut-off (small pressure difference), and corrosive medium. In the oxygen pipeline system of the metallurgy industry, ball valves with strict degreasing treatment are required; when the main line in the oil pipeline and gas pipeline needs to be buried in the ground, the full diameter welded ball valve shall be used; when it is required to have regulating performance, ball valve with special structure with V-shaped opening shall be selected; in petroleum, petrochemical, chemical, electric power, urban construction, the pipeline system with working temperature above 200 degrees can choose the ball valve with metal to metal seal.