| 摘要 |
PURPOSE:To reduce the number of manufacturing processes by slicing a cylindrical plastic body and at the same timer perforning a bending process of the slice. CONSTITUTION:On the circumference of a cylindrical plastic body 1 are ar ranged a cutting means A for slicing the end part of the cylindrical body and a bending process means B for bending the slice 2 into an approximate L-shape. After a bending process, a screw groove 7 is engraved on the inner circumfer ence of a bent part 6 by means of a groove cutting means C. Machining the groove is performed by moving the groove cutting means C by a specified width in the direction of the axis of the cylindrical plastic body 1. Accordingly, adverse effects due to elongation or deformation of a seal ring during bending process is eliminated, making it possible to machine a screw groove of desired depth and shape within a short period of time. |
