The original standard for valve seat leakage rating of control valves was established by the American Institute of Standards and implemented by the American Institute of Fluid Control (ANSI BI6.104 FC170-2). The leakage level standard in the Technical Conditions for Regulating Valves of Power Plants in China is formulated with reference to this standard. Purpose of specifying the seat leakage class. It is to provide users and manufacturers with a method to test the closing performance of the regulating valve or control the leakage capacity of the valve seat. The content discussed in this article can only be used as an example. The valve seat leakage test shall refer to the latest ANSI standard. The actual allowable valve seat leakage of a certain valve depends on the valve diameter and type published by the manufacturer.

The pneumatic ball valve is compact in structure, reliable in sealing, simple in structure, and easy to maintain. The sealing surface and spherical surface are always closed, not easily eroded by media, and easy to operate and maintain. It is suitable for general working media such as water, solvent, acid, natural gas, etc. It is mainly used to cut off or connect the media in the pipeline, and can also be used for fluid regulation and control.