The ball of the cryogenic ball valve is elastic. Ball and seat sealing ring are made of metal materials, sealing pressure is very large, relying on the pressure of the medium itself has not reached the requirements of sealing, must apply external forces. This valve is suitable for high temperature and high pressure medium. Elastic sphere is an elastic groove at the lower end of the inner wall of the sphere to obtain elasticity. When closing the channel, cryogenic ball valves use the wedge head of the stem to expand the ball and seat pressure to seal. Stainless steel ball valve before rotating the ball first release the wedge head, the ball then restore the original shape, stainless steel ball valve makes a small gap between the ball and the seat, low temperature ball valve can reduce friction and operating torque of the sealing surface.
The ball of the low temperature ball valve is fixed and does not move under pressure. Trunnion mounted ball valve with floating seat, by the medium pressure, seat movement, so that the sealing ring on the ball, to ensure sealing. Usually equipped with bearings on the upper and lower shafts of the ball, with small operating torque, low temperature ball valves are 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, the emergence of oil sealing ball valve, low temperature ball valve between the sealing surface pressure injection of special lubricating oil, to form a layer of oil film, that is to enhance the sealing, and reduce the operating torque, more suitable for high pressure large diameter ball valve.
Cryogenic ball valve itself, compact structure, reliable sealing, simple structure, convenient maintenance, sealing surface and the spherical often in the closed state, not easily be medium erosion, easy operation and maintenance, suitable for water, solvents, acids and gas generally working medium, such as low temperature ball valve but also applicable to the working conditions of media, such as oxygen, hydrogen peroxide, methane and ethylene, widely used in various fields. Low temperature ball valves can be integral or modular.
Low temperature ball valve enterprises need to change the existing production relations to strengthen technical innovation in the face of the increasingly serious homogenization problem, now low temperature ball valve is gradually in the wireless cycle into the escape of vicious competition. In this severe situation, valve enterprises need to clearly recognize that low cost, low technology valve products flooded the market, not only disrupt the consumer's judgment and purchase desire, low temperature ball valves also hinder the mature transition of the valve market. Therefore, if the valve enterprises want to improve the production efficiency, it is necessary to change the existing production relationship, increase the investment in the modern production line, low temperature ball valve to strengthen technical innovation.