Process and device for cooling a metal substrate

Patent metadata

Field	Value
Publication number	US-11072839-B2
Application number	US-201615779961-A
Country	US
Kind code	B2
Filing date	Dec 29, 2016
Priority date	Dec 30, 2015
Publication date	Jul 27, 2021
Grant date	Jul 27, 2021

Abstract

A process for cooling a metal substrate running in a longitudinal direction, said process including ejecting at least one first cooling fluid jet on a first surface of said substrate and at least one second cooling fluid jet on a second surface of said substrate, said first and second cooling fluid jets being ejected at a cooling fluid velocity higher than or equal to 5 m/s, so as to form on said first surface and on said second surface a first laminar cooling fluid flow and a second laminar flow respectively, said first and second laminar cooling fluid flows being tangential to the substrate, said first and second laminar cooling fluid flows extending over a first predetermined length and a second predetermined length of the substrate respectively, said first and second lengths being determined so that the substrate is cooled from a first temperature to a second temperature by nucleate boiling.

First claim

What is claimed is:

1. A process of cooling a metal substrate running in a longitudinal direction, said process comprising ejecting at least one first cooling fluid jet on a first surface of the substrate and at least one second cooling fluid jet on a second surface of the substrate,
the first and second cooling fluid jets being ejected at a cooling fluid velocity higher than or equal to 5 m/s, so as to form on the first surface of the substrate and on the second surface of the substrate a first laminar cooling fluid flow and a second laminar cooling fluid flow respectively, the first and second laminar cooling fluid flows being tangential to the substrate, the first and second laminar cooling fluid flows extending over a first predetermined length and a second predetermined length of the substrate respectively,
the first and the second cooling fluid jets each forming during their ejection a predetermined angle with the longitudinal direction, said predetermined angle being comprised between 5° and 25° and said first and second predetermined lengths being determined so that the substrate is cooled from a first temperature to a second temperature by nucleate boiling.

2. The process according to claim 1 , wherein a difference between the first predetermined length and the second predetermined length is lower than 10% of a mean of the first and the second predetermined lengths.

3. The process according to claim 1 , wherein the first cooling fluid jet and the second cooling fluid jet are symmetrical with respect to a median plane of the substrate.

4. The process according to claim 1 , wherein said first and said second cooling fluid jets are ejected from a predetermined distance on said first and second surfaces respectively, said predetermined distance being comprised between 50 and 200 mm.

5. The process according to claim 1 , wherein each of said first and second predetermined lengths is comprised between 0.2 m and 1.5 m.

6. The process according to claim 1 , wherein the first temperature is higher than or equal to 600° C.

7. The process according to claim 6 , wherein the first temperature is higher than or equal to 800° C.

8. The process according to claim 1 , wherein the substrate is running at a speed comprised between 0.2 m/s and 4 m/s.

9. The process according to claim 1 , wherein a mean heat flux extracted from each of the first and second surfaces during the cooling from the first temperature to the second temperature is comprised between 3 and 7 MW/m 2 .

10. The process according to claim 1 , wherein, the substrate has a thickness comprised between 2 and 9 mm, and the substrate is cooled from 800° C. to 550° C. at a cooling rate higher than or equal to 200° C./s.

11. The process according to claim 1 , wherein each of said first and second cooling fluid jets is ejected with a specific cooling fluid flow rate comprised between 360 and 2700 L/min/m 2 .

12. The process according to claim 1 , wherein the substrate is a steel plate.

13. The process according to claim 1 , wherein, the substrate has a width, and said first and second laminar cooling fluid flows extend over the width of the substrate.

14. A method for hot-rolling a metal substrate, said method comprising hot-rolling the metal substrate and cooling the hot-rolled metal substrate with a process according to claim 1 .

15. A method for heat-treating a metal substrate, said method comprising heat-treating the metal substrate and cooling the heat-treated metal substrate with a process according to claim 1 .

Assignees

• Arcelormittal

Inventors

• Hamide Makhlouf
• Romberger Charles
• Borean Jean-Luc
• Régnier Marie-Christine

Classifications

• C21D1/667

  for spray quenching · CPC title

• C21D9/573

  with cooling · CPC title

• B21B45/0218

  for strips, sheets, or plates (B21B45/023, B21B45/0233 take precedence) · CPC title

• C21D11/005 Primary

  for cooling · CPC title

• B21B45/02

  for lubricating, cooling, or cleaning {(in particular in combination with forging or pressing devices B21B15/005, control of flatness or profile using lubricating or cooling B21B37/44)} · CPC title