影响零件形状精度的因素来自机床、夹具、刀具、工件、环境等各个方面。这众多因素的综合作用导致零件产生形状误差。为区别传统形状误差的概念,现给出形状误差统计评定中的定义。先约定,对实际形体的理想形体,其法线的正方向为由零件的实体内向外。则定义:实际形体上的任一点对其理想形体的法向偏离值 t,为实际形体在该点的局部形状 Factors that affect the accuracy of part shape come from machine tools, fixtures, tools, workpieces, environment and other aspects. The combination of these many factors leads to shape error of parts. To distinguish the concept of traditional shape error, the definition of shape error in statistical evaluation is given. The first agreement, the ideal form of the actual form, the positive direction of the normal from the inside of the entity to the outside. Then the definition: the actual body of any point on the ideal body of the normal deviation from the value of t, the actual shape of the body in the local shape