偏心轴在切削加工前的毛坯必须保证φ12外圆和φ20外圆有足够的加工余量。因此,对弯曲变形了的毛坯必须进行校正。原来校正是将工件夹在虎钳上,用铁锤敲工件,因无校正基准,校正后的毛坯仍然得不到正确形状。因而在加工φ12外圆过程中,出现加工余量不均匀,造成了60％的废品率。 The eccentric shaft before cutting roughing must ensure φ12 cylindrical and φ20 cylindrical enough machining allowance. Therefore, the bending deformation of the blank must be corrected. The original correction is to clip the workpiece on the vise, knocking the workpiece with a hammer, because there is no calibration reference, the corrected blank still can not get the correct shape. Thus in processing φ12 cylindrical process, there is uneven machining allowance, resulting in a 60% rejection rate.