Classification of Ball Valves with Different Spherical Cores

Ball valves came out in the 1950s. With the rapid development of science and technology and the continuous improvement of production technology and product structure, in a short period of 40 years, they have rapidly developed into a primary valve class. Ball valves can generally be divided into floating ball valves and fixed ball valves. But what effect do they all have? Now let's do it. The ball of the floating ball valve is floating. Under the effect of medium pressure, the ball can displace and press on the sealing surface of the outlet to ensure the sealing of the outlet. When the ball valve is in the floating ball core, its structure is simple and the sealing is good, but the ball receives all the load from the working medium and passes it to the outlet sealing ring. Therefore, it is necessary to consider whether the sealing ring material can withstand the working load of the ball medium. When the ball is impacted by high pressure, the ball may suffer from deviation. This structure is generally used in low and medium pressure ball valves. The ball body of the so-called fixed ball valve is fixed and does not move after being pressed. Fixed ball valves are equipped with floating seats. After being subjected to medium pressure, the seat moves and the sealing ring is pressed on the ball to ensure sealing. Usually, bearings are installed on the upper and lower axles of the sphere, and the operation torque is small. It is suitable for high pressure and large caliber valves. In order to reduce the operating torque of ball valves and increase the reliability of sealing, oil seal ball valves have been presented in recent years. They not only inject special lubricating oil between sealing surfaces to form a layer of oil film, which enhances the sealing performance, but also reduces the operating torque. They are more suitable for high pressure and large caliber ball valves. There are also ball valves with elastic spherical cores, whose spheres are elastic. Ball and seat seals are made of metal materials. The specific pressure of the seals is very high. The pressure of the medium itself can not meet the requirements of the seals. External force must be applied. This valve is suitable for high temperature and high pressure media. Elastic sphere is an elastic groove opened at the lower end of the sphere wall to obtain elasticity. When closing the passage, use the wedge-shaped head of the stem to make the ball open and the seat press to reach the seal. The wedge head is loosened before the ball is rotated, and the ball is restored to its original shape, so that there is a small gap between the ball and the valve seat, which can reduce the friction and operating torque of the sealing surface.