Patent ID: 7495197
Filing Date: 2009-02-24
Classification: C21D,C22F,G21C,Y02E,Y02P

Abstract:
1. A method for heat treating a fuel assembly channel made of zircaloy, which comprises the steps of; moving continuously the fuel assembly channel relative to a heat-treatment device resulting in longitudinal sections of the fuel assembly channel being heated to a beta phase range with an aid of an inductive heating zone encompassing the fuel assembly channel, the heat-treatment device containing at least first and second heating devices spaced apart from one another in a longitudinal direction of the fuel assembly channel, operate independently of each other, and each of the first and second heating devices having at least one induction coil and together form the inductive heating zone, a fuel assembly channel section entering the inductive heating zone being heated using the first heating device and then heat-treated using the second heating device having less power than the first heating device; cooling each of the longitudinal sections after leaving the inductive heating zone with a cooling device disposed at an axial spacing from said heating zone, in a cooling zone to a temperature within an alpha phase range; and effecting the cooling to the alpha phase range with an aid of a stream of inert gas applied to an entire outer surface of the fuel assembly channel.