HOLE FINISH METHOD BY PRESS FOR ROUND OR IRREGULAR HOLE IN BLANK FOR THERMAL STRESS REMOVAL

摘要

PROBLEM TO BE SOLVED: To resolve the problem that as a hole finish method after heat treatment, a machining work using a lathe or a horning work has been employed heretofore, or a soft nitriding treatment by a low temperature quenching in which carburize-quenching is performed after applying carburize-preventive treatment before heat treatment to restrain the development of hole strain has been employed, however such a conventional method is expensive.;SOLUTION: A hole finish method by a press is disclosed by which after general inexpensive heat treatment, a general press is used, and the hole finish having high accuracy at one stroke-pressing can be easily performed inexpensively, the accuracy after the finishing having such a degree that a squareness of the finished hole to the plane of a blank and a roundness of the hole at a portion becoming an elliptical hole are increased and the mirror-finishing having ≤1.5 S roughness of a circular wall is obtained.;COPYRIGHT: (C)2005,JPO&NCIPI