Publication detail

MINIMIZATION OF SURFACE DEFECTS BY INCREASING THE SURFACE TEMPERATURE DURING THE STRAIGHTENING OF A CONTINUOUSLY CAST SLAB

ŠTĚTINA, J. MAUDER, T. KLIMEŠ, L. KAVIČKA, F.

Original Title

MINIMIZATION OF SURFACE DEFECTS BY INCREASING THE SURFACE TEMPERATURE DURING THE STRAIGHTENING OF A CONTINUOUSLY CAST SLAB

English Title

MINIMIZATION OF SURFACE DEFECTS BY INCREASING THE SURFACE TEMPERATURE DURING THE STRAIGHTENING OF A CONTINUOUSLY CAST SLAB

Type

journal article - other

Language

en

Original Abstract

Surface temperatures of cast slabs on small-radius segments as well as on the unbent areas belong to the parameters that affect the surface quality of continuously cast slabs. Older machines for continuous casting were designed with regard to the quantity (the amount of cast slabs) rather than the quality of the production. Therefore, an adaptation of the secondary cooling is required in order to obtain the desired surface temperatures. The modification consists of a dynamic control of the secondary cooling, surface-temperature monitoring by means of a numerical model of the temperature field as well as a prospective replacement of the cooling nozzles. In order to optimize and control the secondary cooling, characteristics of the nozzles, especially the influences of the water-flow rate, air pressure, casting speed, surface temperatures and heat-transfer coefficient under the nozzles have to be known. Moreover, the heat-transfer coefficient can also be influenced by the age of the nozzles. The paper deals with the relationships between these influences and their impacts on the temperature field of a cast slab. The results are presented for the 1530 mm x 250 mm slabs that are cast in Evraz Vítkovice Steel where the main author's dynamic, 3D solidification model is used, in its off-line version, to control the production interface. The results can be used for the preparation of a real casting process.

English abstract

Surface temperatures of cast slabs on small-radius segments as well as on the unbent areas belong to the parameters that affect the surface quality of continuously cast slabs. Older machines for continuous casting were designed with regard to the quantity (the amount of cast slabs) rather than the quality of the production. Therefore, an adaptation of the secondary cooling is required in order to obtain the desired surface temperatures. The modification consists of a dynamic control of the secondary cooling, surface-temperature monitoring by means of a numerical model of the temperature field as well as a prospective replacement of the cooling nozzles. In order to optimize and control the secondary cooling, characteristics of the nozzles, especially the influences of the water-flow rate, air pressure, casting speed, surface temperatures and heat-transfer coefficient under the nozzles have to be known. Moreover, the heat-transfer coefficient can also be influenced by the age of the nozzles. The paper deals with the relationships between these influences and their impacts on the temperature field of a cast slab. The results are presented for the 1530 mm x 250 mm slabs that are cast in Evraz Vítkovice Steel where the main author's dynamic, 3D solidification model is used, in its off-line version, to control the production interface. The results can be used for the preparation of a real casting process.

Keywords

optimization of the temperature field, surface temperature of a slab, characteristics of nozzles, continuous casting

RIV year

2013

Released

28.06.2013

Publisher

IMT Ljubljana

Location

Ljubljana

Pages from

311

Pages to

316

Pages count

6

Documents

BibTex


@article{BUT100344,
  author="Josef {Štětina} and Tomáš {Mauder} and Lubomír {Klimeš} and František {Kavička}",
  title="MINIMIZATION OF SURFACE DEFECTS BY INCREASING THE SURFACE TEMPERATURE DURING THE STRAIGHTENING OF A CONTINUOUSLY CAST SLAB",
  annote="Surface temperatures of cast slabs on small-radius segments as well as on the unbent areas belong to the parameters that affect the surface quality of continuously cast slabs. Older machines for continuous casting were designed with regard to the quantity (the amount of cast slabs) rather than the quality of the production. Therefore, an adaptation of the secondary cooling is required in order to obtain the desired surface temperatures. The modification consists of a dynamic control of the secondary cooling, surface-temperature monitoring by means of a numerical model of the temperature field as well as a prospective replacement of the cooling nozzles. In order to optimize and control the secondary cooling, characteristics of the nozzles, especially the influences of the water-flow rate, air pressure, casting speed, surface temperatures and heat-transfer coefficient under the nozzles have to be known. Moreover, the heat-transfer coefficient can also be influenced by the age of the nozzles. The paper deals with the relationships between these influences and their impacts on the temperature field of a cast slab. The results are presented for the 1530 mm x 250 mm slabs that are cast in Evraz Vítkovice Steel where the main author's dynamic, 3D solidification model is used, in its off-line version, to control the production interface. The results can be used for the preparation of a real casting process.",
  address="IMT Ljubljana",
  chapter="100344",
  institution="IMT Ljubljana",
  number="3",
  volume="47",
  year="2013",
  month="june",
  pages="311--316",
  publisher="IMT Ljubljana",
  type="journal article - other"
}