METHOD FOR HEAT-TREATING HOLLOW-POWER TRANSMISSION SHAFT

摘要

PROBLEM TO BE SOLVED: To provide a method for heat-treating a hollow-power transmission shaft with which a hardening-crack inspection on the surface part in the inner periphery can be simplified. SOLUTION: A high frequency induction heating coil 10 is disposed at the outer peripheral surface 19 side of a hollow shaft base stock 1' and a high frequency induction-hardening is performed from the outer peripheral surface 1g side to the axial direction zone L. In this time, piping members 11 are connected to both end parts of the hollow shaft base stock 1', and cooling water is made to flow into the inner peripheral part of the hollow shaft base stock 1' through the piping members 11. When the high frequency induction-hardening is performed, a non-hardening layer S0 is formed in a prescribed depth range from the inner peripheral surface 1i by allowing the inner peripheral surface 1i of the hollow shaft base stock 1' to contact with the stream of the cooling water. COPYRIGHT: (C)2006,JPO&NCIPI