The traditional parameters of a piston pin surface include the arithmetical mean deviation of the profile ( R a ) and the mean spacing of the profile irregularities ( S m ) etc.是什么意思_The traditional parameters of a piston pin surface include the arithmetical mean deviation of the profile ( R a ) and the mean spacing of the profile irregularities ( S m ) etc.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句