Patent ID: 7028404
Filing Date: 2006-04-18
Classification: C21D,Y02P,Y10T

Abstract:
1. A method of performing a retrogression heat treatment process on a workpiece comprising the steps of: (a) providing a workpiece having a first portion and a second portion and defining a length; and (b) performing a retrogression heat treatment process on only a portion of the workpiece that is less than the length of the workpiece in a continuous and longitudinal manner from the first portion of the workpiece to the second portion of the workpiece either by (1) supporting an upper end of the workpiece and moving the workpiece vertically relative to an inductive heating coil and quenching ring, by (2) supporting a lower end of the workpiece and moving the workpiece vertically relative to the inductive heating coil and quenching ring, or by (3) initially supporting one of an upper end of the workpiece and a lower end of the workpiece, moving the workpiece vertically relative to an inductive heating coil and quenching ring, and subsequently supporting the other of the upper end and the lower end.