Please using soft-cotton fabric with neutral cleaning solvent such as toothpaste (non-matte type) or suds to wiping door surface when besmirch heavily.

污渍太重时，可使用纯棉软布蘸中性清洗剂：如牙膏（非磨砂类）、肥皂水擦拭。

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Therefore, when using the vacuum pump protection devices need cleaning and drying to remove the low boiling point solvent into the pump, acid gases and solid particles.

因此真空油泵使用时需要净化干燥等保护装置，以除去进入泵中低沸点溶剂、酸碱性气体和固体微粒。

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