Publication detail

Analysis of breakout of concast steel slab via criteria of similarity

KAVIČKA, F. STRÁNSKÝ, K. DOBROVSKÁ, J. SEKANINA, B. ŠTĚTINA, J. MASARIK, M.

Original Title

Analysis of breakout of concast steel slab via criteria of similarity

English Title

Analysis of breakout of concast steel slab via criteria of similarity

Type

conference paper

Language

en

Original Abstract

The so called secondary cooling zone is an important part of the CCM. In this zone a breakout may occur due to an increase of the local and temperature heterogeneity of steel, due to an increase of the stress caused by bending of the slab and by high local concentration of non-metallic slag inclusions. Changes of the chemical composition of the steel during continuous casting are particularly dangerous. In the event that two melts are cast one right after another, i.e. if the melt of the steel with chemical composition A ends and it is immediately followed by the steel B, it may automatically stop the CCM and an atypical breakout may take place. With use of dimensional analysis altogether 8 criteria of similarity were derived according to the PI-theorem. Important data in temperature field of the slab were calculated by the original model. Numerical values of eight criteria were determined for the steels A and B. This application of the theory of physical similarity clearly proved markedly increased tendency of the steel B to breakouts in comparison with the steel A. In order to prevent repetition of this accident of caster for another pair of steels cast immediately one after another, it is necessary to assess the derived individual criteria of similarity for both steels and other operations with these criteria. The way to reduce the risk of breakouts may be found mainly in the change of thermo-physical properties of both steels, consisting primarily of reduction of differences of their chemical composition.

English abstract

The so called secondary cooling zone is an important part of the CCM. In this zone a breakout may occur due to an increase of the local and temperature heterogeneity of steel, due to an increase of the stress caused by bending of the slab and by high local concentration of non-metallic slag inclusions. Changes of the chemical composition of the steel during continuous casting are particularly dangerous. In the event that two melts are cast one right after another, i.e. if the melt of the steel with chemical composition A ends and it is immediately followed by the steel B, it may automatically stop the CCM and an atypical breakout may take place. With use of dimensional analysis altogether 8 criteria of similarity were derived according to the PI-theorem. Important data in temperature field of the slab were calculated by the original model. Numerical values of eight criteria were determined for the steels A and B. This application of the theory of physical similarity clearly proved markedly increased tendency of the steel B to breakouts in comparison with the steel A. In order to prevent repetition of this accident of caster for another pair of steels cast immediately one after another, it is necessary to assess the derived individual criteria of similarity for both steels and other operations with these criteria. The way to reduce the risk of breakouts may be found mainly in the change of thermo-physical properties of both steels, consisting primarily of reduction of differences of their chemical composition.

Keywords

concast slab, chemical composition, heterogeneity, breakout

RIV year

2013

Released

15.05.2013

Publisher

Tanger

Location

Ostrava

ISBN

978-80-87294-39-0

Book

METAL 2013 Conference Proceedings

Edition

1

Pages from

32

Pages to

33

Pages count

2

BibTex


@inproceedings{BUT99734,
  author="František {Kavička} and Karel {Stránský} and Jana {Dobrovská} and Bohumil {Sekanina} and Josef {Štětina} and Miloš {Masarik}",
  title="Analysis of breakout of concast steel slab via criteria of similarity",
  annote="The so called secondary cooling zone is an important part of the CCM. In this zone a breakout may occur due to an increase of the local and temperature heterogeneity of steel, due to an increase of the stress caused by bending of the slab and by high local concentration of non-metallic slag inclusions. Changes of the chemical composition of the steel during continuous casting are particularly dangerous. In the event that two melts are cast one right after another, i.e. if the melt of the steel with chemical composition A ends and it is immediately followed by the steel B, it may automatically stop the CCM and an atypical breakout may take place. With use of dimensional analysis altogether 8 criteria of similarity were derived according to the PI-theorem. Important data in temperature field of the slab were calculated by the original model. Numerical values of eight criteria were determined for the steels A and B. This application of the theory of physical similarity clearly proved markedly increased tendency of the steel B to breakouts in comparison with the steel A. In order to prevent repetition of this accident of caster for another pair of steels cast immediately one after another, it is necessary to assess the derived individual criteria of similarity for both steels and other operations with these criteria. The way to reduce the risk of breakouts may be found mainly in the change of thermo-physical properties of both steels, consisting primarily of reduction of differences of their chemical composition.",
  address="Tanger",
  booktitle="METAL 2013 Conference Proceedings",
  chapter="99734",
  edition="1",
  howpublished="electronic, physical medium",
  institution="Tanger",
  year="2013",
  month="may",
  pages="32--33",
  publisher="Tanger",
  type="conference paper"
}