Breakout prediction method, operation method of continuous casting machine, and breakout prediction device

Patent metadata

Field	Value
Publication number	US-11925974-B2
Application number	US-202118009909-A
Country	US
Kind code	B2
Filing date	Apr 9, 2021
Priority date	Jun 18, 2020
Publication date	Mar 12, 2024
Grant date	Mar 12, 2024

Abstract

A breakout prediction method includes: a step of inputting a dimension of a solid product withdrawn from a mold in a continuous casting machine; a step of detecting a temperature of the mold by a plurality of thermometers embedded in the mold; a step of executing interpolation processing on the detected temperatures detected by the plurality of thermometers according to the dimension of the solid product; a step of calculating, based on the temperatures calculated by executing the interpolation processing, a component in a direction orthogonal to an influence coefficient vector obtained by principal component analysis as a degree of deviation from during a normal operation in which a breakout has not occurred; and a step of predicting a breakout based on the degree of deviation.

First claim

The invention claimed is:

1. A breakout prediction method comprising:
a step of inputting a dimension of a solid product withdrawn from a mold in a continuous casting machine;
a step of detecting a temperature of the mold by a plurality of thermometers embedded in the mold;
a step of executing interpolation processing on the detected temperatures detected by the plurality of thermometers according to the dimension of the solid product;
a step of calculating, based on temperatures calculated by executing the interpolation processing, a component in a direction orthogonal to an influence coefficient vector obtained by principal component analysis as a degree of deviation from during a normal operation in which a breakout has not occurred; and
a step of predicting a breakout based on the degree of deviation.

2. The breakout prediction method according to claim 1 , wherein the step of executing the interpolation processing includes
calculating the temperatures by executing the interpolation processing on the detected temperature of each of the plurality of thermometers, at a center point of each of a plurality of calculation cells equally divided according to the dimension of the solid product.

3. The breakout prediction method according to claim 2 , wherein a number of the calculation cells is kept constant even when the dimension of the solid product is changed.

4. The breakout prediction method according to claim 3 , wherein the step of calculating as the degree of deviation includes
obtaining an average value of a temperature of each of the plurality of calculation cells located at a same distance from an upper end of the mold in a casting direction of a molten steel with respect to the mold,
obtaining a difference from the average value for the temperature of each of the plurality of calculation cells, and
calculating the degree of deviation from the obtained difference using the influence coefficient vector.

5. The breakout prediction method according to claim 2 , wherein the step of calculating as the degree of deviation includes
obtaining an average value of a temperature of each of the plurality of calculation cells located at a same distance from an upper end of the mold in a casting direction of a molten steel with respect to the mold,
obtaining a difference from the average value for the temperature of each of the plurality of calculation cells, and
calculating the degree of deviation from the obtained difference using the influence coefficient vector.

6. The breakout prediction method according to claim 5 , wherein the step of predicting the breakout includes
predicting the breakout based on an adjacency of the calculation cell in which an absolute value of the degree of deviation exceeds a preset second threshold when a time change rate of the degree of deviation exceeds a preset first threshold.

7. The breakout prediction method according to claim 6 , wherein the step of predicting the breakout includes
a step of giving a first score to the calculation cell in which the degree of deviation exceeds the second threshold,
a step of calculating a second score from the first score based on the adjacency of the calculation cell to which the first score is given, and
a step of predicting the breakout based on the second score.

8. The breakout prediction method according to claim 1 , wherein the influence coefficient vector is a sensitivity coefficient vector having a sensitivity coefficient of each of the plurality of thermometers as a component.

9. An operation method of a continuous casting machine, the method comprising
reducing a casting speed at which molten steel is poured into the mold when a breakout is predicted based on the breakout prediction method according to claim 1 .

10. A breakout prediction device comprising:
an input unit configured to input a dimension of a solid product withdrawn from a mold in a continuous casting machine;
a plurality of thermometers embedded in the mold and configured to detect a temperature of the mold;
an interpolation processing execution unit configured to execute interpolation processing on the detected temperatures detected by the plurality of thermometers according to the dimension of the solid product;
a degree-of-deviation calculation unit configured to calculate, based on temperatures calculated by executing the interpolation processing, a component in a direction orthogonal to an influence coefficient vector obtained by principal component analysis as a degree of deviation from during a normal operation in which a breakout has not occurred; and
a breakout prediction unit configured to predict a breakout based on the degree of deviation.

Assignees

• Jfe Steel Corp

Inventors

• Masuda Ryosuke
• Hashimoto Yoshinari
• Matsui Akitoshi
• Morita Shugo
• Hayashida Tatsuro
• Koriyama Taiga
• Hirata Takehide

Classifications

• B22D11/182 Primary

  by measuring temperature · CPC title

• B22D2/00

  Arrangement of indicating or measuring devices, e.g. for temperature or viscosity of the fused mass · CPC title

• B22D11/04 Primary

  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

• B22D11/16 Primary

  Controlling or regulating processes or operations · CPC title

• B22D11/18

  for pouring (B22D11/20 takes precedence) · CPC title