大孔径薄壁零件在机械加工中的装夹变形较难避免。通常采用的三爪或四爪卡盘夹持,由于夹持点少,因而薄壁工件的径向刚度差。为达到所需要的有效夹持力,工件局部径向变形必须很大,这样加工出来的工件多角形明显,残余应力大;同时由于断面形状上下不一定对称和工件材质的不均匀性,以及沿夹持母线上作用力的不均布,夹持时工件的变形多数呈 Large-aperture thin-walled parts in the machining of the folder deformation is difficult to avoid. The usual three-jaw or four-jaw chuck clamping, the clamping point is less, so that the thin-walled workpiece radial stiffness difference. In order to achieve the required effective clamping force, the workpiece local radial deformation must be large, so that the workpiece polygon is obvious, the residual stress is large; at the same time as the cross-sectional shape of the upper and lower symmetry and workpiece material is not uniform, Clamping force on the bus uneven cloth, the workpiece when the clamping deformation was mostly