METHOD FOR OPTICALLY DETERMINING THE TEMPERATURE OF A MOLTEN METAL, AND REELING DEVICE FOR CARRYING OUT SAID METHOD

Abstract

A method for optically determining the temperature of a molten metal with a measuring device, including calibrating a replacement measuring chain by a measuring chain as a system-internal measuring standard. The measuring device includes an optical waveguide, to guide electromagnetic radiation emitted from the metal or from the tip of the optical waveguide to an optical detector, at least one replacement optical waveguide, an optical detector for determining the temperature of the metal from an analysis of the electromagnetic radiation, a measuring chain, in which the optical waveguide is the measurement recorder, and at least one replacement measuring chain, in which a replacement optical waveguide is the measurement recorder. A reeling device includes a conveying device for successive reeling of the optical waveguide from a stock and of the replacement optical waveguide from a replacement stock, a receiving device for a stock and at least one replacement stock.

Claims

1. A method for optically determining the temperature of a molten metal with a measuring device comprising an optical waveguide, in order to guide electromagnetic radiation emitted from the metal or from the tip of the optical waveguide to an optical detector, at least one replacement optical waveguide, an optical detector for determining the temperature of the metal from an analysis of the electromagnetic radiation, a measuring chain, in which the optical waveguide is the measurement recorder, at least one replacement measuring chain, in which the replacement optical waveguide is the measurement recorder, characterized by calibration of the replacement measuring chain by means of the measuring chain as a system-internal measurement standard.

2. The method according to claim 1, characterized by calibration of the measuring chain by means of a system-external measurement standard, preferably a thermal element.

3. The method according to claim 2, characterized in that the optical waveguide is successively reeled, by means of a conveying device of a reeling device of the measuring device, off a stock and the replacement optical waveguide is successively reeled off a replacement stock.

4. The method according to one of claim 3, characterized in that the calibration of the replacement measuring chain occurs shortly before consumption of the stock.

5. The method according to claim 4, characterized in that the optical waveguide for determining the calibration value and the replacement optical waveguide for determining the test value record the electromagnetic radiation of the molten melt at essentially the same measurement point.

6. The method according to claim 5, characterized in that an optical multiplexer controls whether the signal from the optical waveguide or the signal from the replacement optical waveguide is supplied to the optical detector.

7. The method according to claim 6, characterized in that another replacement measuring chain is calibrated by means of a previously calibrated replacement measuring chain as a system-internal measurement standard.

8. A reeling device for a method for optically determining the temperature of a molten metal in which, by means of an optical waveguide, electro-magnetic radiation emitted from the metal or from the tip of the optical waveguide is guided to an optical detector, wherein the reeling device comprises a conveying device for successive reeling of the optical waveguide from a stock and of the replacement optical waveguide from a replacement stock and a receiving device for a stock and at least one replacement stock.

9. The reeling device according to claim 8, characterized in that the conveying device has at least one line which is flowed through by fluid, wherein the optical waveguide and/or the replacement optical waveguide is transported in the line by means of the fluid flow.

10. The reeling device according to claim 9, characterized in that the conveying device has at least two counter-rotating rollers, with at least one roller being a drive roller and with the rollers transporting the optical waveguide and/or replacement optical waveguide which is guided through the gap between the rollers.

11. The reeling device according to claim 9, characterized in that the stock and/or replacement stock is a spool, loop, ball or the like.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0037] The invention is explained in greater detail below with reference to a drawing showing only one exemplary embodiment. The only FIGURE shown therein is a schematic depiction of the reeling device for carrying out a method for optically determining the temperature of a molten metal.

DETAILED DESCRIPTION

[0038] The FIGURE shows a reeling device 1 with a receiving device 2 and a conveying device 3.

[0039] A stock 4 and a replacement stock 5 are located in the receiving device 2. The stock is a spool, around which an optical waveguide 6 is wound. The replacement stock is also a spool, around which a replacement optical waveguide 7 is wound however.

[0040] The conveying device 3 is a line which is flowed through by fluid. In this example it serves both for the transport of the optical waveguide 6 and of the replacement optical waveguide 7. The transport fluid is introduced via a fluid input 8 into the line which is flowed through by fluid. (The fluid source is not depicted here.)

[0041] A container 9 is also depicted, which contains molten metal 10. The container 9 is connected to the line 3 flowed through by fluid by means of a floor opening.

[0042] If fluid flows via the fluid input 8 into the line 3 flowed through by fluid, the optical waveguide 6 or the replacement optical waveguide 7 is supplied to the molten metal 10 via the floor opening of the container 9. The optical waveguide 6 or replacement optical waveguide 7 there picks up the electromagnetic radiation of the molten metal 10 and guides it to an optical detector 11, which converts the optical signals into electrical signals. The electrical signals can be further processed by a signal analysis 12 in order to determine the temperature of the molten metal 10.

[0043] An optical multiplexer 13 is connected upstream of the optical detector. The optical multiplexer 13 controls whether the signal of the optical waveguide 6 or the signal of the replacement optical waveguide 7 is supplied to the optical detector 11.

[0044] In the depicted exemplary arrangement, both the optical waveguide 6 and the replacement optical waveguide 7 are located with their ends in the molten metal 10. This arrangement depicts in particular the moment of the system-internal calibration, in which the calibration value is determined by means of the optical waveguide 6 and the test value is determined by means of the replacement optical waveguide 7.