JPH042709A - Instrument for continuously measuring temperature of molten iron - Google Patents

Abstract

PURPOSE:To automatically detect variation of emissivity and to measure temp. of molten iron with high accuracy by measuring temp. at tip part in a protecting tube submerged into the molten iron with a radiation thermometer and correcting this output with the measured temp. with a consumable type R thermocouple. CONSTITUTION:The hemisphere-shaped tip part of radiation thermometer composed of a detecting head 5, connecting tube 6 and the protecting tube 7 is submerged into the molten iron 2 flowing down in an iron tapping trough 1. This radiation thermometer detects the temp. at the tip part in the above protecting tube 7 and this is processed with a signal processing circuit 10 to output the temp. signal. This temp. signal is recorded with a recorder 11 and also, the molten iron temp. is calculated with a computer 12 based on the above output and the prescribed correction factor. In the above molten iron temp. continuously measuring instrument, based on the output of the above radiation thermometer and the molten iron temp. measured with the consumable type R thermocouple 13, the above correction factor is corrected and the corrected correction factor is used to execute calculation of the molten iron temp. By this method, regardless of the variation of emissivity of the molten iron 2 and the protecting tube 7, the temp. of molten iron 2 can be measured with high accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a continuous measurement device for hot metal temperature, and in particular to eliminating the influence of emissivity fluctuations.

[Prior Art] FIG. 6 is an explanatory diagram showing the configuration of a conventional continuous hot metal temperature measuring device. In the figure, (1) is the tap water, (2) is the hot metal flowing in the tap water (1), and (3) is the slag floating on the hot metal (2). (4) is a cover attached to cover the tap trough (1). (5) is a detection head of the radiation thermometer, (6) is a connecting tube, and (7) is a protective tube with a closed tip. This radiation thermometer (5
〉, the connecting pipe (8) and the protective pipe (7) are integrally constructed, and protrude to the bottom side of the tap trough (1) through the opening of the cover (4), and the protective pipe (7) Immersed in hot metal (2).

The conventional hot metal continuous temperature measurement device is configured as described above, and the detection head (5) of the radiation thermometer continuously measures the temperature of the hot metal (2) flowing through the tap pipe (1). At this time, the protective tube (7) is immersed in the hot metal (2), and therefore is not affected by the slag (3).
) is used to measure the temperature of hot metal (2).

[Problem to be solved by the invention] The conventional hot metal temperature continuous measuring device as described above is
) The temperature of the hot metal is measured by receiving the energy of the hot metal (2) without being affected by the hot metal (2) in the hot metal gutter (1).
There is a problem in that measurement errors occur if the emissivity of the protection tube (7) or the emissivity of the protective tube (7) itself changes over time.

This invention was made in order to solve this problem, and it is possible to automatically detect the change in emissivity as described above and measure the temperature of hot metal with high precision. The purpose is to provide a measuring device.

[Means for Solving the Problems] A continuous hot metal temperature measuring device according to the present invention includes a radiation thermometer having a hemispherical tip and measuring the temperature at the internal tip of a protection tube immersed in hot metal; A hot metal temperature calculation means that calculates the hot metal temperature based on the output of the thermometer and a predetermined correction coefficient, and a correction coefficient that is calibrated based on the output of the radiation thermometer and the hot metal temperature measured by the consumable type R thermocouple. and correction coefficient calculation means for outputting the calibrated correction coefficient to the hot metal temperature calculation means.

Further, the continuous hot metal temperature measuring device according to the present invention has a hemispherical tip and measures the temperature of the internal tip of the protective tube immersed in the hot metal based on a predetermined emissivity and outputs it as the hot metal temperature. calibrating the emissivity based on the thermometer and the output of the radiation thermometer and the hot metal temperature measured by the consumable R thermocouple;
and emissivity calculation means for outputting the calibrated emissivity to the radiation thermometer.

[Function] In this invention, the hot metal temperature is calculated and determined based on the output of the radiation thermometer and a predetermined correction coefficient. Calibration is based on the hot metal temperature. Therefore, even if the emissivity of the radiation thermometer changes, the change is absorbed by calibrating the correction coefficient, resulting in highly accurate measurement results.

Further, in this invention, the emissivity of the radiation thermometer is calibrated based on the output of the radiation thermometer and the hot metal temperature measured by the consumable type R thermocouple. For this reason, even if the emissivity of the radiation thermometer changes, the change is detected and measured.
The measurement results are highly accurate.

[Example] Fig. 1 is a block diagram showing the configuration of a continuous hot metal temperature measuring device according to an embodiment of the present invention, and Fig. 2 is an explanatory diagram showing the relationship between the continuous hot metal temperature measuring device and measurement parts. be.

In FIG. 2, the same reference numerals as in FIG. 6 are the same or corresponding parts, and the explanation thereof will be omitted. (10) is a signal processing circuit that processes the signal detected by the detection head (5) of the radiation thermometer and outputs a temperature signal.

(11) is a recorder that records the temperature signal that is the output of the signal processing circuit (10). (12) is an electronic computer which performs signal processing on the output of the signal processing circuit (10) to obtain the hot metal temperature taking into account changes in emissivity. (18) is a consumable R thermocouple (13), which is not installed all the time, but is installed, for example, once a day.
) to measure the temperature.

Next, in FIG. 1, (20) is the detection head (20) in FIG.
5) and a signal processing circuit (lO), and this radiation thermometer (20) measures the emissivity assuming that it is constant.

(21) to (24) respectively illustrate the functions of the electronic computer (12), and (21) is the radiation thermometer (20).
) is a hot metal temperature calculation means that calculates the hot metal temperature in consideration of emissivity based on the output of 1 and the correction coefficient. (22) is an output means for sending out the output of the temperature calculation means (21).

(23) is a correction coefficient calibration means for calibrating a correction coefficient based on the temperature detected by the consumable type R thermocouple (13) and the hot metal temperature calculated by the temperature calculation means (21). (24) is a storage means, in which an initial value of a predetermined value is initially written, and then sequentially rewritten when the correction coefficient is calibrated by the correction coefficient calibrating means (24).

FIG. 3 is a flowchart showing the operation of the hot metal temperature continuous measuring device having the above configuration, and the operation will be explained below based on this flowchart.

First, the initial value k of the correction coefficient. is stored in the storage means (24) (811). Thereafter, the temperature calculation means (21) calculates the output of the radiation thermometer (20) and the initial value k of the correction coefficient set in the storage means (24). The hot metal temperature is calculated based on (S12). For example, the output of the radiation thermometer (20) is T
1, the hot metal temperature T2 is obtained by the following equation.

T2-koTl The hot metal temperature T2 determined here is outputted by the output means (22) (813). For example, display it on a CRT,
Alternatively, it may be accumulated as control data for an expert system for controlling a blast furnace.

Thereafter, the correction coefficient calibration means (23) uses the consumable type R thermocouple (
514 to determine whether the measurement result of 13) has been input.
), and if it is not entered here, then it is necessary to judge whether there is an instruction to terminate or not (5lB), and if there is no instruction to terminate, the value measured by the radiation thermometer (20) above is set to the initial value k. . (S12), (S1
3).

Next, the consumable type R thermocouple (13) is installed and the hot metal sluice (1
) and its output is output to the correction coefficient calibration means (23).
) determines that there is an input from the consumable type R thermocouple (13) (Si2) and the correction coefficient calibration means (23)
compares the hot metal temperature measured by the consumable R thermocouple (13) and the hot metal temperature T2 calculated by the hot metal temperature calculating means (21) to determine whether they match (8
15). If it is determined that they match, there is no need to calibrate the correction coefficient, and you can proceed to the next measurement (
S12).

If it is determined that they do not match, then a correction calculation of the correction coefficient is performed (S17). For example, let the hot metal temperature measured by the consumable R thermocouple (13) at this time be TO, and calculate 1 as the correction coefficient in relation to the hot metal temperature T1 measured by the radiation thermometer (20) using the following equation.

kl-TL /TO Then, 1 is set to this calibrated correction coefficient by the storage means (24
), and this correction coefficient is set to 1 and is used in calculations by the temperature calculation means (21) until the next calibration.

In this embodiment, in order to bring the emissivity of the protection tube (7) close to "1", the immersion depth L of the protection tube (7) and the radius r of the protection tube (7) are L/r. > 5. Furthermore, Z r B 2 series ceramic is used as the material for the protective tube (7).

FIG. 4 is a block diagram showing the configuration of a continuous hot metal temperature measuring device according to another embodiment. This example uses a radiation thermometer (
The emissivity of 20) is calibrated based on the measurement results of the consumable type R thermocouple (13), and corresponds to the temperature calculation means (21> and storage means (24)) in the embodiment shown in FIG. There is no configuration to do so.

FIG. 5 is a flowchart showing the operation of the hot metal temperature continuous measuring device having the above configuration, and the operation will be explained below based on this flowchart.

First, the initial value ε of emissivity. is set on the radiation thermometer (20) (S2L). After that, the radiation thermometer (20) measures the hot metal temperature based on the set initial value ε0 of emissivity (S22). For example, if the detection data of the detection head (5) of the radiation thermometer (20) is T1, then the hot metal temperature T2
is obtained by the following equation.

T2-Tl/ε0 The hot metal temperature T2 measured here is outputted by the output means (22) (S23). For example, display it on a CRT,
Alternatively, it may be accumulated as control data for an expert system for controlling a blast furnace.

Thereafter, the emissivity calibration means (23) uses the consumable type R thermocouple (1
524) to determine whether the measurement results of 3) have been input.
, here, it is assumed that there is no instruction to terminate or not (826), and if there is no instruction to terminate, the measurement by the radiation thermometer (20) is set to the initial value ε. It is repeated based on the emissivity of < (S22)
, (S23).

Next, the consumable type R thermocouple (13) is installed and the hot metal sluice (1
) and its output is output to the emissivity calibration means (23). A judgment is made (S24). The emissivity calibration means (23) calculates the hot metal temperature TO measured by the consumable type R thermocouple (13) and the hot metal temperature T measured by the radiation thermometer (20) at that time.
2 and determine whether they match (S2
5). If it is determined that they match, there is no need to calibrate the emissivity, so proceed to the next measurement (S2
2).

If it is determined that they do not match, then a calibration calculation of emissivity is performed (S27). For example, in this case, the consumable type R
Based on the hot metal temperature TO measured by the thermocouple (13) and the detection data T1 of the detection head (5) of the radiation thermometer (20), the emissivity ε1 after calibration is determined by the following equation.

ε1-Tl/T.

Then, this calibrated emissivity ε1 is determined by the radiation thermometer (20
), and then this emissivity ε1 is used until this emissivity is calibrated.

Note that the steps in the flowcharts in Figures 3 and 5 (
It goes without saying that when determining whether they match or do not match in S14) and (S24), even if the difference between the two falls within a predetermined range, it may be treated as a match.

[Effects of the Invention] As described above, according to the present invention, the correction coefficient or emissivity is calibrated based on the output of the radiation thermometer and the hot metal temperature measured by the consumable type R thermocouple. Even if the emissivity of the thermometer changes, measurements can be made that correspond to the changes, and the measurement results are highly accurate.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a continuous hot metal temperature measuring device according to an embodiment of the present invention, and FIG. 2 is an explanatory diagram showing the relationship between the continuous hot metal temperature measuring device and measurement parts. FIG. 3 is a flowchart showing the operation of the measuring device shown in FIG. 1;
Fig. 4 is a block diagram showing the configuration of a continuous hot metal temperature measuring device according to another embodiment of the present invention, Fig. 5 is a flowchart showing the operation of the measuring device of Fig. 4, and Fig. 6 is a conventional continuous hot metal temperature measuring device. FIG. 2 is an explanatory diagram showing the configuration of a measuring device. Agent Patent Attorney Muneharu Sasaki 11%lI Figure 2 Figure 3 Figure

Claims (2)

[Claims] (1) A radiation thermometer with a hemispherical tip that measures the temperature of the internal tip of the protective tube that is immersed in the hot metal, and calculates the hot metal temperature based on the output of the radiation thermometer and a predetermined correction coefficient. a correction coefficient that calibrates a correction coefficient based on the output of the radiation thermometer and the hot metal temperature measured by the consumable type R thermocouple, and outputs the calibrated correction coefficient to the hot metal temperature calculation means; 1. A continuous hot metal temperature measuring device, characterized in that it has a calculation means. (2) A radiation thermometer with a hemispherical tip that measures the temperature of the internal tip of the protection tube immersed in hot metal based on a predetermined emissivity and outputs it as the hot metal temperature; Continuous hot metal temperature measurement characterized by having an emissivity calculation means for calibrating emissivity based on the hot metal temperature measured by the consumable type R thermocouple and outputting the calibrated emissivity to the radiation thermometer. Device.