GB2079197A - Cooling a Continuous Casting - Google Patents

Abstract

Cooling medium is delivered to and absorbed at the external surface of a porous surface layer on a casting support roll as the roll is rotating, the medium being delivered remote from the casting for subsequent release in the vicinity of the casting as the respective surface area draws near to or comes in contact with the casting line. The roll may be partly immersed in a reservoir of the cooling medium so as to absorb the latter as the roll rotates. A roll for use in this technique has a roll core with a solid continuous outer surface to which the porous layer is applied, and is thus economic to produce.

Description

SPECIFICATION Process for Cooling the Line Surface of a Casting Line The invention relates to a process for cooling the line surface of a casting line in continuous casting using one or more rolls having a porous surface layer. The invention also relates to a continuous casting roll suitable for use in the process.

Continuous casting rolls are known which have a porous sintered peripheral layer and an internal cooling system, which is connected with the peripheral layer, so that cooling medium can issue from the roll surface through the peripheral layer.

By this means, both a cooling of the roll itself and of the line surface is possible. This form of roll is, however, very expensive to produce.

The present invention seeks to provide for cooling of the line surface in a continuous casting line by means of a continuous casting roll, which does not require an internal cooling system. According to the invention, a roll having a porous surface layer is used but, while the roll is rotating, a cooling medium is fed to the roll surface layer from an external source at a region remote from the casting line, the cooling medium being released from the roll adjacent the point of contact between the roll and the casting line.

Preferably, the cooling medium is released from the surface layer as the respective roll area draws near to or comes in contact with the line.

The preferred roll used to carry out this process has a roll core onto which a porous sinter layer is applied. The thickness of the sinter layer must guarantee a sufficient admission of absorbtion of the cooling medium, and the quantity of cooling medium to be absorbed by the porous layer should also be large enough for the radiant energy striking the roll to be absorbed by the cooling medium, without the roll, for example with water as cooling medium, becoming hotter than 1 00C and to provide for cooling of the casting line. In a typical roll, its diameter is substantially 400 mm, and the thickness of a porous sintered layer is at least 10 mm with an open porosity of substantially 24%. The cooling capacity of such a roll is then approximately 10 1 per minute.

The cooling medium may be introduced into the surface layer by the roll being immersed in the cooling fluid on a side facing away from the casting line, thus absorbing until it is saturated.

On rotation of the roll and as a respective surface area draws near to or comes in contact with the line, the cooling medium is released and absorbs the radiant energy striking the roll. In this embodiment, the cooling medium is absorbed and released continuously and the cooling effect can be accurately controlled by monitoring the amount of medium taken up by the roll at the absorbtion stage.

In the process of the invention, not only is the cooling of the roll assured, but also the cooling of the casting line. Secondary cooling, which would otherwise have been usual practice, can therefore be dispensed with.

Claims

1. A process for cooling the line surface of a casting line using a continuous casting roll having a porous surface layer in which, while the roll is rotating, a cooling medium is fed to the roll surface layer from an external source at a region remote from the casting line, the cooling medium being released from the roll adjacent the point of contact between the roll and the casting line.

2. A process according to Claim 1 wherein the cooling medium is released from the roll as the respective roll area comes into contact with the casting line.

3. A process according to Claim 1 or Claim 2 wherein the cooling medium is introduced continuously to the surface layer as the roll rotates.

4. A process according to Claim 3 wherein the surface layer is partially immersed in a bath of liquid cooling medium.

5. A process according to any preceding Claim wherein the cooling medium is water.

6. A process for cooling the line surface of a casting line according to Claim 1 and substantially as herein described.

7. A continuous casting roll for use in a process according to any preceding Claim, comprising a roll core with a solid continuous outer surface, and a porous layer applied to the continuous surface for receiving and releasing a said cooling medium at its external surface.

8. A continuous casting roll for use in a process according to any of Claims 1 to 6 comprising a roll core and a porous surface sintered layer, the total roll diameter being substantially 400 mm, and the porous surface layer thickness being at least 10 mm with an open porosity of substantially 24%.

9. A continuous casting roll for use in a process according to Claim 1 substantially as herein described.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (9)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Process for Cooling the Line Surface of a Casting Line The invention relates to a process for cooling the line surface of a casting line in continuous casting using one or more rolls having a porous surface layer. The invention also relates to a continuous casting roll suitable for use in the process. Continuous casting rolls are known which have a porous sintered peripheral layer and an internal cooling system, which is connected with the peripheral layer, so that cooling medium can issue from the roll surface through the peripheral layer. By this means, both a cooling of the roll itself and of the line surface is possible. This form of roll is, however, very expensive to produce. The present invention seeks to provide for cooling of the line surface in a continuous casting line by means of a continuous casting roll, which does not require an internal cooling system. According to the invention, a roll having a porous surface layer is used but, while the roll is rotating, a cooling medium is fed to the roll surface layer from an external source at a region remote from the casting line, the cooling medium being released from the roll adjacent the point of contact between the roll and the casting line. Preferably, the cooling medium is released from the surface layer as the respective roll area draws near to or comes in contact with the line. The preferred roll used to carry out this process has a roll core onto which a porous sinter layer is applied. The thickness of the sinter layer must guarantee a sufficient admission of absorbtion of the cooling medium, and the quantity of cooling medium to be absorbed by the porous layer should also be large enough for the radiant energy striking the roll to be absorbed by the cooling medium, without the roll, for example with water as cooling medium, becoming hotter than 1 00C and to provide for cooling of the casting line. In a typical roll, its diameter is substantially 400 mm, and the thickness of a porous sintered layer is at least 10 mm with an open porosity of substantially 24%. The cooling capacity of such a roll is then approximately 10 1 per minute. The cooling medium may be introduced into the surface layer by the roll being immersed in the cooling fluid on a side facing away from the casting line, thus absorbing until it is saturated. On rotation of the roll and as a respective surface area draws near to or comes in contact with the line, the cooling medium is released and absorbs the radiant energy striking the roll. In this embodiment, the cooling medium is absorbed and released continuously and the cooling effect can be accurately controlled by monitoring the amount of medium taken up by the roll at the absorbtion stage. In the process of the invention, not only is the cooling of the roll assured, but also the cooling of the casting line. Secondary cooling, which would otherwise have been usual practice, can therefore be dispensed with. Claims

1. A process for cooling the line surface of a casting line using a continuous casting roll having a porous surface layer in which, while the roll is rotating, a cooling medium is fed to the roll surface layer from an external source at a region remote from the casting line, the cooling medium being released from the roll adjacent the point of contact between the roll and the casting line.

2. A process according to Claim 1 wherein the cooling medium is released from the roll as the respective roll area comes into contact with the casting line.

3. A process according to Claim 1 or Claim 2 wherein the cooling medium is introduced continuously to the surface layer as the roll rotates.

4. A process according to Claim 3 wherein the surface layer is partially immersed in a bath of liquid cooling medium.

5. A process according to any preceding Claim wherein the cooling medium is water.

6. A process for cooling the line surface of a casting line according to Claim 1 and substantially as herein described.

7. A continuous casting roll for use in a process according to any preceding Claim, comprising a roll core with a solid continuous outer surface, and a porous layer applied to the continuous surface for receiving and releasing a said cooling medium at its external surface.

8. A continuous casting roll for use in a process according to any of Claims 1 to 6 comprising a roll core and a porous surface sintered layer, the total roll diameter being substantially 400 mm, and the porous surface layer thickness being at least 10 mm with an open porosity of substantially 24%.

9. A continuous casting roll for use in a process according to Claim 1 substantially as herein described.