表面粗糙度是反映零件表面微观几何形状 误差的尺寸特征量,是评定零件表面质量的指标 之一,它的大小直接影响零件的使用性能。能否 正确合理地标注表面粗糙度,对提高设计质量是 很重要的。其标注的依据是GB/T131-93《机械 制图 表面粗糙度符号、代号及其注法》。为了更 好地贯彻新标准,应当通过新旧标准异同的对比 Surface roughness is the size of the surface features to reflect the micro-geometry of the error characteristics of the amount of parts is to assess the quality of the surface of one of the indicators, the size of its direct impact on the performance of parts. Whether the surface roughness can be correctly and reasonably marked is very important to improve the design quality. The label is based on GB / T131-93 “mechanical drawing surface roughness symbols, code and note.” In order to better implement the new standard, we should compare the similarities and differences between the old and new standards