If the spacing between mating flanges is tight, the valve sealing surface should be coated with a lubricant to prevent distortion during installation.是什么意思_If the spacing between mating flanges is tight, the valve sealing surface should be coated with a lubricant to prevent distortion during installation.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句