Apparatus and method for the treatment of a flat steel product, taking place in throughput

Patent metadata

Field	Value
Publication number	US-9551046-B2
Application number	US-201214116530-A
Country	US
Kind code	B2
Filing date	Mar 30, 2012
Priority date	May 10, 2011
Publication date	Jan 24, 2017
Grant date	Jan 24, 2017

Abstract

An apparatus and a method for the treatment of a flat steel product, taking place in throughput. The apparatus includes an indirectly heated annealing furnace chamber, a conveyor device for continuously conveying the flat steel product over a conveyor path leading from an entry to an exit of the annealing furnace chamber, and nozzle arrangements for feeding atmosphere gas, which is reactive in relation to the flat steel product, into the annealing furnace chamber. A controlled treatment of the flat steel product includes a first nozzle arrangement, from which a gas jet induces a first gas flow towards the entry of the annealing furnace chamber and sweeping over the surface of flat steel product to be treated. A second nozzle arrangement includes a gas jet which induces a second gas flow directed towards the exit of the annealing furnace chamber and sweeping over the surface of flat steel product.

First claim

The invention claimed is:

1. An apparatus for the treatment of a flat steel product, taking place in throughput, comprising: an indirectly heated annealing furnace chamber, having a conveyor device for continuously conveying the flat steel product over a conveyor path leading from an entry of the annealing furnace chamber to an exit of the annealing furnace chamber, and having nozzle arrangements for feeding atmosphere gas, which is reactive in relation to the flat steel product, into the annealing furnace chamber,
wherein the nozzle arrangements include a first nozzle arrangement, from which a gas jet, which induces a first gas flow directed towards the entry of the annealing furnace chamber and sweeping over the surface of flat steel product to be treated, emerges during the treatment, and a second nozzle arrangement, from which a gas jet, which induces a second gas flow directed towards the exit of the annealing furnace chamber and sweeping over the surface of flat steel product to be treated, emerges during the treatment, and
wherein the first and second nozzle arrangements are provided in the annealing furnace chamber and at least one of the nozzles of one of the nozzle arrangements emits a gas jet which is directed towards the lower side of the flat steel product to be treated, while at least one of the nozzles of one of the nozzle arrangements emits a gas jet which is directed towards the upper side of the flat steel product to be treated.

2. The apparatus according to claim 1 , further comprising a control device is provided, which controls the delivery of atmosphere gas to the annealing furnace chamber in such a way that a positive pressure of at least 0.001 bar relative to the ambient pressure is maintained in the annealing furnace chamber during the treatment operation.

3. The apparatus according to claim 1 , wherein the nozzle arrangements respectively comprise at least one nozzle and an incidence angle of the gas jet emerging from the at least one nozzle of a nozzle arrangement is varied in the range of from 0° to 90°.

4. The apparatus according to claim 1 , wherein the orientation of the at least one nozzle is adjustable.

5. The apparatus according to claim 1 , wherein the at least one nozzle of the nozzle arrangements is connected to an N 2 supply and an O 2 supply.

6. The apparatus according to claim 5 , wherein the N 2 or O 2 gas flow flowing into the respective nozzle is adjustable.

7. The apparatus according to claim 1 , wherein the longitudinal side surfaces of the annealing furnace chamber are curved concavely as seen in cross section.

8. The apparatus according to claim 1 , wherein the annealing furnace chamber is connected to at least one second annealing furnace chamber, in which the flat steel product to be treated undergoes a further treatment in an atmosphere which differs from the atmosphere of the first annealing furnace chamber.

9. A method for treating a flat steel product comprising:
conveying the flat steel product in continuous throughput through an indirectly heated annealing furnace chamber from its entry to its exit; and
introducing an atmosphere which is reactive in relation to the flat steel product into the annealing furnace chamber through nozzle arrangements, being maintained in the annealing furnace chamber,
wherein a first gas flow, directed towards the entry of the annealing furnace chamber and sweeping over the surface of the flat steel product to be treated is generated by one of the nozzle arrangements, and in that a second gas flow directed towards the exit of the annealing furnace chamber and sweeping over the surface of the flat steel product to be treated, is generated by a second nozzle arrangement, and
wherein the first and second nozzle arrangements are provided in the annealing furnace chamber and gas flows travel spirally around the flat steel product to be treated.

10. The method according to claim 9 , wherein in relation to the longitudinal extent of the annealing furnace chamber, the gas flow directed towards the entry and the gas flow directed towards the exit respectively have their origin in the middle of the annealing furnace chamber.

11. The method according to claim 9 , wherein the gas jet respectively emerging from the nozzles of the nozzle arrangements is an N 2 /O 2 mixture, the O 2 fraction of which is 0.01-20 vol. %.

12. The method according to claim 9 , wherein the flow rate of the gas jets respectively emerging from the nozzle arrangements is 60-180 m/s.

13. The method according to claim 9 , wherein the temperature of the flat steel product to be treated is 450-950° C.

14. The method according to claim 9 , wherein the temperature of the gas jets introduced into the annealing furnace chamber is 100-1050° C.

15. The method according to claim 9 , wherein a positive pressure of the reactive atmosphere of at least 0.001 bar relative to the ambient pressure is maintained in the annealing furnace chamber during the treatment.

Assignees

• Blumenau Marc
• Machalitza Karsten
• Peters Michael
• Schoenenberg Rudolf
• Zeizinger Sabine
• Norden Martin
• Thyssenkrupp Steel Europe Ag

Inventors

• Blumenau Marc
• Machalitza Karsten
• Peters Michael
• Schoenenberg Rudolf
• Zeizinger Sabine
• Norden Martin

Classifications

• C21D1/26

  Methods of annealing · CPC title

• F27B9/06

  heated without contact between combustion gases and charge; electrically heated · CPC title

• F27D7/02

  Supplying steam, vapour, gases or liquids · CPC title

• F27B9/3005

  arrangements for circulating gases · CPC title

• F27D99/0075

  Gas curtain seals · CPC title