Process and device for inline pickling of hot strips downstream of thin-slab production installations

US5876522A · kind A · utility

Assignee

• Mannesmann AG · DE

Inventors

• Dieter Figge · Essen, DE
• Helmut Humbs · Duisburg, DE
• Michael Haentjes · Essen, DE
• Rainer Lorenz · Nettetal, DE

Key dates

• Filing date: Feb 5, 1997
• Grant date: Mar 2, 1999
• Expiry date: Feb 5, 2017

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C21D9/573
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

A process for pickling a strip which is produced in a thin slab installation and subsequently hot-rolled, especially a low-carbon steel strip, in a continuous process immediately following the rolling process. The process includes the following sequence of steps: gently cooling the strip exiting the rolling mill at .gtoreq.880.degree. C. in a first cooling zone to 850.degree. to 680.degree. C., balancing surface temperature and core temperature of the strip in a first recovery zone to a uniform cross section temperature of approximately 680.degree. C., gently cooling the strip in an immediately adjoining second cooling zone from 680.degree. to 480.degree. C., and balancing surface temperature and core temperature in a second recovery zone to a uniform cross section temperature of approximately 480.degree. C. The process continues by drastically cooling the strip from 480.degree. C. to approximately 95.degree. C. in a third cooling zone, balancing surface temperature and core temperature in a third recovery zone to a uniform cross section temperature of approximately 100.degree. C., guiding the strip through a number of connectable and disconnectable chemical pickling vessels at app…