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How to judge the leaking is internal or external
- Mar 09, 2018 -

In daily use, valves often encounter all sorts of malfunctions. The valve leakage is one of the most common breakdowns. And there are internal leakage and external leakage. What's the difference between these two?


The internal leakage of the valve generally refers to medium leaking or dripping, and so on when the valve is completely closed. Generally speaking, the sealing is not good, hard to be completely sealed. It is usually caused by erosion or abrasion of the medium, or with impurities. Even if the valve screw (stem) is tight in place, the medium can flow through the gap between the valve core and the valve body.


External leakage of the valve generally refers to the medium leaks at the external sealing part of the valve packing when the valve is fully closed or opened. It is caused by untight sealing between the valve and the flange or thread connection, or untight sealing between the stem and gland, or sand hole on the body, or medium erosion.