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.

Second, in the process of cleaning the butterfly valve, the liquid will move up and down in a team way, so that there will be a certain gap between the accessories, which is convenient for the ultrasonic effect. At the same time, when the liquid comes into contact with the surface of the workpiece, there will be some friction, in order to improve the cleaning speed, and the cleaning effect is also significant;