Thermal treatment method of metal tube and said thermal treatment apparatus

Abstract

The present invention provides a heat-treatment technique. It is characterized by that when said invention adopts a continuous mobile inductive heating and cooling operation mode to treat the external surface of workpieces of roll, etc., at the same time it can inhibit the outer diameter deformation due to heat treatment. At the same time of making heat treatment of external surface of said workpiece of roll, etc. the inner surface of said workpiece can be cooled, and the depth of penetration of the induced current in the induction heating process can be limited in a certain range to reduce deformation of its outer diameter.

Description

technical field [0001] The present invention relates to the technology of performing heat treatment such as quenching on the outer surface of a metal cylinder represented by a hollow roll shell workpiece that is often used in a metal plate processing production line by using induction heating, and provides a technology that can reduce the occurrence of heat treatment during the heat treatment process. A heat treatment method and a device used in the method for achieving a desired heat treatment depth by deforming the outer diameter of a cylinder with high power efficiency. Background technique [0002] In the past, the heat treatment of metal cylinders such as hollow roll shells using induction heating was done in Figure 7 In the state shown in , that is, on the outer surface side of the metal cylinder 1, the heating coil 2 surrounding the cylinder 1 and the small section 1a along the axial direction of the cylinder is arranged, and the coil is fed into the The high-frequen...

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