| 摘要 |
PURPOSE:To prevent lowering in strength of a part formed by means of drawing by cutting off the internal surface of the part of a hollow driving shaft, which has been formed by drawing, so as to remove the flaws on the internal surface. CONSTITUTION:In a hollow driving shaft 1, smaller-diameter parts 4 formed by drawing are provided at both ends of a metallic pipe made of steel or the like. Flaws 10 caused by buckling due to plastic deformation are created at times on the internal surface of the smaller-diameter parts which have been formed by drawing. In this connection, the internal surface is cut off up to the position as shown by two-dot-and-dash-lines in the figure by using either a drill or a reamer so as to remove the flaws 10 on the internal surface. |
