Method and device for hot-dip coating a metal strand

US7662438B2 · kind B2 · utility

Assignee

• SMS SIEMAG AG · DE

Inventors

• Rolf Brisberger · Issum, DE
• Bernhard Tenckhoff · Duisburg, DE
• Holger Behrens · Reutlingen, DE
• Bodo Falkenhahn · Mülheim an der Ruhr, DE
• Walter Trakowski · Duisburg, DE
• Michael Zielenbach · Siegen, DE
• Robert Jürgens · Remscheid, DE

Key dates

• Filing date: Nov 15, 2003
• Grant date: Feb 16, 2010
• Expiry date: Jul 29, 2025

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C23C2/24
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

The invention relates to a method for hot-dip coating a metal strand (1), especially a steel strip, according to which the metal strand (1) is vertically guided through a container (3) accommodating the molten coating metal (2) and through a guide channel (4) disposed upstream thereof. An electromagnetic field is generated in the area of the guide channel (4) by means of at least two inductors (5) disposed at both sides of the metal strand (1) to retain the coating material (2) in the container (3). In order to stabilize the metal strand (1) in a center position in the guide channel (4), an electromagnetic field, superimposing the electromagnetic field of the inductors (5), is generated by means of at least two additional coils (6) disposed at both sides of the metal strand (1). In order to improve efficiency of the control of the metal strand in the guide channel, the center position of the metal strand (1) in the guide channel (4) is stabilized in a closed control loop by carrying out the following steps: a) detecting the position (s, s′, s″) of the metal strand (1) in the guide channel (4); b) measuring the induced current (IInd) in the inductors (5); c) measuring the induced cu…