METHOD AND APPARATUS FOR HEATING STEEL SHEET

• US 20140124503A1
• Filed: 07/25/2012
• Published: 05/08/2014
• Est. Priority Date: 07/28/2011
• Status: Active Grant

• Current Assignee: JFE Steel Corporation (JFE Holdings Incorporated)
• Original Assignee: JFE Steel Corporation (JFE Holdings Incorporated)
• Inventors: Hino, Yoshimichi, Sugihara, Hirokazu
• Granted Patent: US 10,455,648 B2
• Time in Patent Office: Days
• US Class Current: 219/645
• CPC Class Codes: C21D 1/42 Induction heating
• CPC Class Codes: C21D 1/60 Aqueous agents
• CPC Class Codes: C21D 8/12 during manufacturing of articles with special electromagnetic properties
• CPC Class Codes: C21D 9/60 with induction heating
• CPC Class Codes: F27D 2099/0015 Induction heating
• CPC Class Codes: H05B 6/101 for local heating of metal pieces
• CPC Class Codes: Y02P 10/25 Process efficiency

Abstract

The invention proposes a method for heating a steel sheet wherein the generation of buckling can be prevented regardless of presence or absence of rolls restraining the steel sheet by antecedently heating the widthwise central portion of the steel sheet with a solenoid type induction heating coil having a convex form projected onto the surface of the steel sheet toward an upstream side in rapidly heating the continuously traveling steel sheet, whereby an isotherm of the steel sheet in the heating is a convex form toward the upstream side, so that a large wrinkle is generated on the steel sheet, and also proposes a heating apparatus used in this method.

Claims

1. A method for heating a steel sheet by heating a continuously traveling steel sheet, characterized by antecedently heating a widthwise central portion of the steel sheet.

2. A method for heating a steel sheet according to claim 1, wherein the steel sheet is heated so that an isotherm in the heating is a convex form toward an upstream side.

3. A method for heating a steel sheet according to claim 2, wherein the convex form is circular arc or V-shaped.

4. An apparatus for heating a steel sheet by heating a continuously traveling steel sheet, characterized in that a heating means for the steel sheet is disposed so as to antecedently heat a widthwise central portion of the steel sheet.

5. An apparatus for heating a steel sheet according to claim 4, wherein the heating means for the steel sheet is a solenoid type induction heating coil in which a form projected on the surface of the steel sheet is a convex form toward an upstream side.

6. An apparatus for heating a steel sheet according to claim 5, wherein the convex form is circular arc or V-shaped.

7. An apparatus for heating a steel sheet according to claim 4, wherein the heating means for the steel sheet is by disposing an antecedent heating means for heating a widthwise central portion of the steel sheet toward an upstream side of a solenoid type induction heating coil in which a form projected on the surface of the steel sheet is rectangular.

8. An apparatus for heating a steel sheet according to claim 7, wherein the antecedent heating apparatus is a transverse type induction heating coil.

9. An apparatus for heating steel sheet according to claim 4, wherein a pinch roll is disposed between the solenoid type induction heating coil and a downstream sheet traveling roll.