Method and device for controlling flatness

US6513358B2 · kind B2 · utility

Assignee

• ABB AB · SE

Inventors

• Lars Jonsson · Visby, SE
• Klaus Meyer · Kaarst, DE

Key dates

• Filing date: Dec 22, 2000
• Grant date: Feb 4, 2003
• Expiry date: Dec 22, 2020

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B21B2001/228
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

A method for controlling flatness of a strip (1) of rolled material rolled to a first flatness target and coiled and that is subsequently uncoiled, and a system which employs the method. Measurements of the flatness of the strip (1) during rolling are compared to both the first flatness target and to a second flatness target, a Mill Flatness Target 2. A flatness target for each of one or more subsequent processes, a Post Rolling Flatness Target (PRFT) and a measured flatness error is used to adapt a control signal for a mill stand (5) to control and regulate the flatness of subsequent production of rolled material of the same specification. The adaption may be made using different statistical techniques including fuzzy logic and neuro-fuzzy logic control methods. In the preferred embodiment, flatness measurements after decoiling are also fed forward to at least one subsequent process 12 and used to adapt control signals to regulate flatness of the current strip in the subsequent process 12. The advantages include that the rolled strip is more flat after decoiling, and that flatness control over the strip in a subsequent process is more accurate.