Advantages and disadvantages of ball valves

Advantages of ball valves:

①It has the lowest flow resistance (actually 0); ②Because it will not get stuck when working (when there is no lubricant), it can be reliably used in corrosive media and low-boiling liquids; ③Under higher pressure It can be completely sealed within the temperature range and temperature range; ④It can realize fast opening and closing, and the opening and closing time of some structures is only 0.05~0.1s to ensure that it can be used in the automation system of the test bench. When opening and closing the valve quickly, there is no shock in operation. ⑤The spherical closure can be automatically positioned at the boundary position; ⑥The working medium is sealed reliably on both sides; ⑦The sealing surface of the ball and the valve seat is isolated from the medium when the valve is fully opened and fully closed, so the medium passing through the valve at high speed will not Causes the erosion of the sealing surface; ⑧ compact structure and light weight, it can be considered as the most reasonable valve structure for low-temperature media systems; ⑨ symmetrical valve body, especially the welded valve body structure, can well withstand the stress from the pipeline ⑩The closing piece can withstand the high pressure difference when it is closed. ⑾The ball valve with fully welded body can be directly buried in the ground, so that the internal parts of the valve are not corroded, and the maximum service life can reach 30 years. It is the most ideal valve for oil and natural gas pipelines.

Disadvantages of ball valve:

①Because the main seat sealing ring material of the ball valve is polytetrafluoroethylene, it is inert to almost all chemical substances, and has a small friction coefficient, stable performance, not easy to age, wide temperature application range and excellent sealing performance The comprehensive characteristics. However, the physical properties of PTFE, including high expansion coefficient, sensitivity to cold flow and poor thermal conductivity, require the design of valve seat seals to focus on these characteristics. Therefore, when the sealing material becomes hard, the reliability of the seal is impaired. Moreover, PTFE has a low temperature resistance rating and can only be used at less than 180°C. Above this temperature, the sealing material will deteriorate. When considering long-term use, it will generally only be used at 120°C. ② Its adjustment performance is worse than that of the stop valve, especially the pneumatic valve (or electric valve).