In-mold solidified shell thickness estimation apparatus, in-mold solidified shell thickness estimation method, and continuous steel casting method

Patent metadata

Field	Value
Publication number	US-12174010-B2
Application number	US-202017761642-A
Country	US
Kind code	B2
Filing date	Sep 4, 2020
Priority date	Oct 3, 2019
Publication date	Dec 24, 2024
Grant date	Dec 24, 2024

Abstract

An in-mold solidified shell thickness estimation apparatus includes: an input device; a model database configured to store a model formula and a parameter related to a solidification reaction of a molten steel inside a mold of a continuous casting facility; and a heat transfer model calculator configured to estimate an in-mold solidified shell thickness by calculating temperature distributions of the mold and of the molten steel inside the mold by solving a three-dimensional unsteady heat transfer equation. The heat transfer model calculator is configured to correct errors in a temperature of a mold copper plate and in an amount of heat removed from the mold, by correcting an overall heat transfer coefficient between the mold copper plate and the solidified shell.

First claim

The invention claimed is:

1. An in-mold solidified shell thickness estimation apparatus comprising:
an input device configured to receive an input of:
a measurement result of a temperature of molten steel in a tundish of a continuous casting facility;
measurement results of a width of a strand being cast and of a casting speed in the continuous casting facility;
measurement results of a temperature of a mold copper plate and of an amount of heat removed from a mold in the continuous casting facility; and
input values of a chemical composition of the molten steel and of the thickness of the strand;

a model database configured to store a model formula and a parameter related to a solidification reaction of the molten steel inside the mold of the continuous casting facility; and
a heat transfer model calculator configured to estimate an in-mold solidified shell thickness by calculating temperature distributions of the mold and of the molten steel inside the mold by solving a three-dimensional unsteady heat transfer equation using the measurement result of the temperature of the molten steel in the tundish of the continuous casting facility, the measurement results of the width of the strand being cast and of the casting speed in the continuous casting facility, the measurement results of the temperature of the mold copper plate and of the amount of heat removed from the mold in the continuous casting facility, and the input values of the chemical composition of the molten steel and of the thickness of the strand, and the model formula and the parameter, wherein
the heat transfer model calculator is configured to correct errors in the temperature of the mold copper plate and in the amount of heat removed from the mold, by correcting an overall heat transfer coefficient between the mold copper plate and the solidified shell.

2. The in-mold solidified shell thickness estimation apparatus according to claim 1 , wherein the heat transfer model calculator is configured to correct the errors in the mold copper plate temperature and in the amount of heat removed from the mold, by correcting a thermal conductivity of a region having a temperature higher than a solidus temperature and lower than a liquidus temperature of the molten steel, in addition to correcting the overall heat transfer coefficient.

3. The in-mold solidified shell thickness estimation apparatus according to claim 2 , wherein the heat transfer model calculator is configured to
calculate an amount of solidification shrinkage of the molten steel, from the temperature distribution of the molten steel inside the mold, and
calculate the overall heat transfer coefficient between the mold and the solidified shell based on the amount of solidification shrinkage.

4. The in-mold solidified shell thickness estimation apparatus according to claim 3 , wherein the input values of the chemical composition of the molten steel and the strand thickness are measurement results of the chemical composition of the molten steel and the strand thickness.

5. The in-mold solidified shell thickness estimation apparatus according to claim 2 , wherein the input values of the chemical composition of the molten steel and the strand thickness are measurement results of the chemical composition of the molten steel and the strand thickness.

6. The in-mold solidified shell thickness estimation apparatus according to claim 1 , wherein the heat transfer model calculator is configured to
calculate an amount of solidification shrinkage of the molten steel, from the temperature distribution of the molten steel inside the mold, and
calculate the overall heat transfer coefficient between the mold and the solidified shell based on the amount of solidification shrinkage.

7. The in-mold solidified shell thickness estimation apparatus according to claim 6 , wherein the input values of the chemical composition of the molten steel and the strand thickness are measurement results of the chemical composition of the molten steel and the strand thickness.

8. The in-mold solidified shell thickness estimation apparatus according to claim 1 , wherein the input values of the chemical composition of the molten steel and the strand thickness are measurement results of the chemical composition of the molten steel and the strand thickness.

9. An in-mold solidified shell thickness estimation method comprising:
an input step of inputting:
a measurement result of a temperature of molten steel in a tundish of a continuous casting facility;
measurement results of a width of a strand being cast and of a casting speed in the continuous casting facility;
measurement results of a temperature of a mold copper plate and of an amount of heat removed from a mold in the continuous casting facility; and
input values of a chemical composition of the molten steel and of the thickness of the strand;

a heat transfer model calculating step of estimating an in-mold solidified shell thickness by calculating temperature distributions of the mold and of the molten steel inside the mold by solving a three-dimensional unsteady heat transfer equation using the measurement result of the temperature of the molten steel in the tundish of the continuous casting facility, the measurement results of the width of the strand being cast and of the casting speed in the continuous casting facility, the measurement results of the temperature of the mold copper plate and of the amount of heat removed from the mold in the continuous casting facility, and the input values of the chemical composition of the molten steel and of the thickness of the strand, and a model formula and a parameter related to a solidification reaction of the molten steel inside the mold of the continuous casting facility, wherein
the heat transfer model calculating step includes a step of correcting errors in the mold copper plate temperature and in the amount of heat removed from the mold, by correcting an overall heat transfer coefficient between the mold copper plate and the solidified shell.

10. The in-mold solidified shell thickness estimation method according to claim 9 , wherein
the heat transfer model calculating step includes a step of correcting the errors in the mold copper plate temperature and the amount of heat removed from the mold by correcting a thermal conductivity of a region having a temperature higher than a solidus temperature and lower than a liquidus temperature of the molten steel, in addition to correcting the overall heat transfer coefficient.

11. The in-mold solidified shell thickness estimation method according to claim 10 , wherein the heat transfer model calculating step includes a step of:
calculating an amount of solidification shrinkage of the molten steel, from the temperature distribution of the molten steel inside the mold, and
calculating the overall heat transfer coefficient between the mold and the solidified shell based on the amount of solidification shrinkage.

12. The in-mold solidified shell thickness estimation method according to claim 11 , wherein the input values of the chemical composition of the molten steel and the strand thickness are measurement results of the chemical composition of the molten steel and the strand thickness.

13. The in-mold solidified shell thickness estimation method according to claim 10 , wherein the input values of the chemical composition of the molten steel and the strand thickness are measurement results of the chemical composition of the molten steel and the strand thickness.

14. The in-mold solidified shell thickness estimation method according to claim 9 , wherein the heat transfer model calculating step in

Assignees

• Jfe Steel Corp

Inventors

• Masuda Ryosuke
• Hashimoto Yoshinari
• Matsui Akitoshi
• Morita Shugo
• Hayashida Tatsuro
• Koriyama Taiga
• Sato Miho

Classifications

• B22D11/16

  Controlling or regulating processes or operations · CPC title

• B22D11/225

  for secondary cooling · CPC title

• B22D46/00

  Controlling, supervising, not restricted to casting covered by a single main group, e.g. for safety reasons (controlling or regulating in general G05) · CPC title

• B22D11/055

  Cooling the moulds {(B22D11/04 takes precedence)} · CPC title

• B22D11/22

  for cooling cast stock or mould · CPC title