它们被喷了油以防止侵蚀。

They are sprayed with oil to prevent corrosion.

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硬面楔塞阀可用于高温腐蚀或侵蚀蒸汽和油，或者石油蒸汽应用领域。

Wedgeplug valves with hard facings are recommended for high temperature corrosive and erosive steam and oil or oil vapor services.

youdao

硬面楔塞阀可用于高温腐蚀或侵蚀蒸汽和油，或者石油蒸汽应用领域。

Wedgeplug valves with hard facings are recommended for high temperature corrosive and erosive steam and oil or oil vapor services.

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