机械密封：密封面、密封垫及轴封等元件必须完好，否则将导致过度泄漏，对有磨损或损伤的元件必须更换。

Mechanical seal: seal face, gasket and shaft seal, etc parts must be undamaged, otherwise will result in over leakage, sure to change parts with wear and tear or damage.

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机械密封在两密封面间有极小的缝隙，容许少量液体(每分钟5 - 10滴)泄漏。

The seal has an almost microscopic clearance between the faces and a small amount of liquid (5 or 10 drops per minute) is allowed to leak out.

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阀瓣与阀体密封面经过精密研磨，组装完毕经过100%试压，全部达到零泄漏。

Valve with the valve sealing surface through precision grinding, assembly, after 100% completion of pressure test, all to achieve zero leakage.

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