Advantages And Disadvantages Of Brass Ball Valves

The ball valve is evolved from the 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 to cut off, distribute and change the direction of medium flow on the pipeline. The ball valve designed as a V-shaped opening also has a good flow adjustment function.

Advantages:

① has the lowest flow resistance (actually 0); ball valve manufacturers

②Because it won't get stuck during work (when there is no lubricant), it can be reliably used in corrosive media and low-boiling liquid;

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

④ Quick opening and closing can be achieved. The opening and closing time of some structures is only 0.05 ~ 0.1s to ensure that it can be used in the automatic system of the test bench. When opening and closing the valve quickly, the operation has no impact;

⑤The spherical closure can be automatically positioned at the boundary position;

⑥ The working medium is reliable and sealed on both sides;

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

⑧ Compact structure and light weight, it can be considered as the most reasonable valve structure for low temperature medium system;

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

⑩The closing piece can withstand the high pressure difference during closing. ⑾The ball valve with fully welded body can be buried directly in the ground, so that the internal parts of the valve will not be eroded, and the maximum service life can reach 30 years.

Disadvantages:

①Because the main seat sealing material of ball valve is PTFE, it is inert to almost all chemical substances, and has a small friction coefficient, stable performance, not easy to age, wide temperature range and excellent sealing performance Comprehensive characteristics. However, the physical characteristics of PTFE, including a high expansion coefficient, sensitivity to cold flow and poor thermal conductivity, require that the design of the valve seat seal must be carried out around these characteristics. Therefore, when the sealing material becomes hard, the reliability of the seal is destroyed. Moreover, PTFE has a low temperature resistance level and can only be used at less than 180 ° C. Above this temperature, the sealing material will age. When considering long-term use, it is generally not used at 120 ℃.

② Its regulating performance is worse than the globe valve, especially the pneumatic valve (or electric valve)