Ball Valve Advantages And Disadvantages

Ball valve Advantages and Disadvantages

It evolved from a plug valve. Its opening and closing part is a ball. The ball is rotated 90° around the axis of the valve stem to achieve the purpose of opening and closing. The ball valve is mainly used for cutting off, distributing and changing the flow direction of the medium in the pipeline. The ball valve designed as a V-shaped opening also has a good flow adjustment function.

Advantages:

①has 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 point liquids;

③In a larger pressure and temperature range, it can achieve complete sealing;

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, the operation has no impact;

⑤The spherical closing piece can be automatically positioned on the boundary position;

⑥The working medium is reliably sealed on both sides;

⑦When fully open and fully closed, the sealing surface of the ball and the valve seat is isolated from the medium, so the medium passing through the valve at high speed will not cause the erosion of the sealing surface;

⑧ compact structure and light weight, it can be considered as the most reasonable valve structure for cryogenic medium system;

⑨The valve body is symmetrical, especially the welded valve body structure, which can withstand the stress from the pipeline well;

⑩The closing piece can withstand the high pressure difference when closing. 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 gas pipelines.

Disadvantages:

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 grade 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.

②Its regulation performance is worse than that of globe valves, especially pneumatic valves (or electric valves).