Continuous casting apparatus and continuous casting method for multilayered slab

Patent metadata

Field	Value
Publication number	US-10987730-B2
Application number	US-201615771834-A
Country	US
Kind code	B2
Filing date	Oct 31, 2016
Priority date	Oct 30, 2015
Publication date	Apr 27, 2021
Grant date	Apr 27, 2021

Abstract

A continuous casting apparatus for a multilayered slab includes a ladle having a molten steel supply nozzle; a tundish having a first retention portion that receives supply of the molten steel from the ladle through the molten steel supply nozzle and has a first immersion nozzle and a second retention portion that is adjacent to the first retention portion with a flow path interposed therebetween and has a second immersion nozzle; an addition mechanism that adds a predetermined element to the molten steel in the second retention portion; and a casting mold that receives supply of the molten steel from the tundish.

First claim

The invention claimed is:

1. A continuous casting apparatus for a multilayered slab comprising:
a ladle having a molten steel supply nozzle;
a tundish having a first retention portion that receives supply of the molten steel from the ladle through the molten steel supply nozzle and has a first immersion nozzle, and a second retention portion that is adjacent to the first retention portion with a flow path interposed therebetween and has a second immersion nozzle;
an addition mechanism that adds a predetermined element to the molten steel in the second retention portion; and
a casting mold that receives supply of the molten steel from an inside of the first retention portion through the first immersion nozzle and receives supply of the molten steel from an inside of the second retention portion through the second immersion nozzle,
wherein, in the case of being seen in a planar view, in a path from the molten steel supply nozzle to the second immersion nozzle, the molten steel supply nozzle, the first immersion nozzle, the flow path, and the second immersion nozzle are disposed in this order,
wherein the tundish further has a weir, by which the tundish is partitioned into the first retention portion and the second retention portion, and
wherein, an opening portion which communicates the first retention portion and the second retention portion is formed in the weir as the flow path.

2. The continuous casting apparatus for a multilayered slab according to claim 1 ,
wherein, in the case of being seen in a cross section perpendicular to a communication direction of the flow path,
a cross-sectional area of the flow path is 10% or more and 70% or less of a cross-sectional area of the molten steel present in the first retention portion.

3. The continuous casting apparatus for a multilayered slab according to claim 2 , further comprising:
a direct-current magnetic field generator that generates a direct-current magnetic field in the casting mold along a thickness direction of the casting mold.

4. A continuous casting method for a multilayered slab using the continuous casting apparatus for a multilayered slab according to claim 3 , the method comprising:
supplying the molten steel present in the ladle to the tundish;
adding the predetermined element to the molten steel present in the second retention portion of the tundish; and
supplying the molten steel present in the first retention portion of the tundish and the molten steel present in the second retention portion of the tundish to an inside of the casting mold.

5. The continuous casting apparatus for a multilayered slab according to claim 2 , further comprising:
an electromagnetic stirring device that stirs an upper portion of the molten steel present in the casting mold.

6. A continuous casting method for a multilayered slab using the continuous casting apparatus for a multilayered slab according to claim 2 , the method comprising:
supplying the molten steel present in the ladle to the tundish;
adding the predetermined element to the molten steel present in the second retention portion of the tundish; and
supplying the molten steel present in the first retention portion of the tundish and the molten steel present in the second retention portion of the tundish to an inside of the casting mold.

7. The continuous casting apparatus for a multilayered slab according to claim 1 , further comprising:
a direct-current magnetic field generator that generates a direct-current magnetic field in the casting mold along a thickness direction of the casting mold.

8. The continuous casting apparatus for a multilayered slab according to claim 7 , further comprising:
an electromagnetic stirring device that stirs an upper portion of the molten steel present in the casting mold.

9. A continuous casting method for a multilayered slab using the continuous casting apparatus for a multilayered slab according to claim 7 , the method comprising:
supplying the molten steel present in the ladle to the tundish;
adding the predetermined element to the molten steel present in the second retention portion of the tundish; and
supplying the molten steel present in the first retention portion of the tundish and the molten steel present in the second retention portion of the tundish to an inside of the casting mold.

10. The continuous casting apparatus for a multilayered slab according to claim 1 , further comprising:
an electromagnetic stirring device that stirs an upper portion of the molten steel present in the casting mold.

11. A continuous casting method for a multilayered slab using the continuous casting apparatus for a multilayered slab according to claim 10 , the method comprising:
supplying the molten steel present in the ladle to the tundish;
adding the predetermined element to the molten steel present in the second retention portion of the tundish; and
supplying the molten steel present in the first retention portion of the tundish and the molten steel present in the second retention portion of the tundish to an inside of the casting mold.

12. A continuous casting method for a multilayered slab using the continuous casting apparatus for a multilayered slab according to claim 1 , the method comprising:
supplying the molten steel present in the ladle to the tundish;
adding the predetermined element to the molten steel present in the second retention portion of the tundish; and
supplying the molten steel present in the first retention portion of the tundish and the molten steel present in the second retention portion of the tundish to an inside of the casting mold.

13. The continuous casting method for a multilayered slab according to claim 12 ,
wherein, in the supplying of the molten steel present in the first retention portion of the tundish and the molten steel present in the second retention portion of the tundish,
in a case in which the tundish is seen in a planar view, when an area of the molten steel present in the first retention portion is represented by ST 1 (m 2 ), an area of the molten steel present in the second retention portion is represented by ST 2 (m 2 ),
an amount of molten steel supplied from the first retention portion to the casting mold is represented by Q 1 (kg/s), and an amount of molten steel supplied from the second retention portion to the casting mold is represented by Q 2 (kg/s),
the molten steel is supplied to the casting mold so as to satisfy Expression (1) below,
( Q 1 /ST 1 )<( Q 2 /ST 2 )  Expression (1).

14. A continuous casting apparatus for a multilayered slab, comprising:
a ladle having a molten steel supply nozzle;
a tundish having a first retention portion that receives supply of the molten steel from the ladle through the molten steel supply nozzle and has a first immersion nozzle, and a second retention portion that is adjacent to the first retention portion with a flow path interposed therebetween and has a second immersion nozzle;
an addition mechanism that adds a predetermined element to the molten steel in the second retention portion; and
a casting mold that receives supply of the molten steel from an inside of the first retention portion through the first immersion nozzle and receives supply of the molten steel from an inside of the second retention portion through the second immersion nozzle,
wherein, in the case of being seen in a planar view, in a path from the molten steel supply nozzle to the second immersion nozzle, the molten steel supply nozzle, the first immersion nozzle, the flow path, and the second immersion nozzle are disposed in this order,
wherein the flow path is formed of a

Assignees

• Nippon Steel & Sumitomo Metal Corp
• Nippon Steel Corp

Inventors

• Harada Hiroshi
• Sakamoto Masashi
• Ito Yui
• Sasai Katsuhiro

Classifications

• B22D11/007

  of composite ingots, i.e. two or more molten metals of different compositions being used to integrally cast the ingots (casting of composite ingots in definite lengths B22D7/02) · CPC title

• B22D11/103 Primary

  Distributing the molten metal, e.g. using runners, floats, distributors · CPC title

• B22D11/04

  into open-ended moulds (B22D11/06, B22D11/07 take precedence; plants for continuous casting, e.g. for upwardly drawing the strand B22D11/14) · CPC title

• B22D11/115

  by using magnetic fields · CPC title

• B22D11/108 Primary

  Feeding additives, powders, or the like · CPC title