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.

• 用表面轮廓仪测量磨削加工的活塞销轴,得到各试件粗糙轮廓算术平均偏差、轮廓微观不平度平均间距数值。