JP2683203B2 - Measuring method of temperature of profile - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plurality of profile members having a flange portion and a web portion facing each other at an angle of less than 180 °, such as a web portion surface for measuring the surface temperature of H-section steel during rolling. At least one of the surfaces to be temperature-measured, relates to a method of measuring the surface temperature of the temperature-measured surface by measuring the radiant energy of the temperature-measured surface,
The present invention relates to a temperature measuring method for a profile that can reduce the temperature measurement error.

[0002]

2. Description of the Related Art Surface temperature measurement using a radiation thermometer is generally performed in measuring the temperature of a steel material moving on a rolling line or the like, or measuring the temperature of a continuously cast slab. The surface temperature measurement using this radiation thermometer measures the intensity of the radiant energy radiated by a high temperature object to be measured according to its temperature, and based on this, measures the surface temperature of the object to be temperature measured. That is. According to the surface temperature measurement using such a radiation thermometer, the surface temperature of the temperature measurement target object can be measured in a non-contact manner.

[0003]

However, according to the investigation by the inventor, for example, in the H-section steel being rolled, the surface temperature of a part of the inner surface of the flange portion or the surface of the web portion is measured by using a radiation thermometer. It has been found that it is not possible to obtain sufficient temperature measurement accuracy when attempting to perform measurement by using the above method. That is, the H-section steel is composed of both flange portions and a web portion between these flange portions, but is measured when the surface temperature of the web portion is measured using a single radiation thermometer. Since the energy is the sum of the radiant energy of the web surface and the reflected energy of the radiant surface of the flange surface, it has been confirmed that sufficient temperature measurement accuracy cannot be obtained.

The present invention has been made to solve the above-mentioned conventional problems, and at least one surface to be temperature-measured among a plurality of surfaces facing each other at an angle of less than 180 ° is to be measured. It is an object of the present invention to provide a temperature measuring method for a profile, which can reduce a temperature measurement error when measuring the surface temperature of the surface to be measured by measuring the radiant energy of.

[0005]

SUMMARY OF THE INVENTION The present invention relates to at least one temperature measurement surface of a plurality of surfaces facing each other at an angle of less than 180 ° of a profile having a flange portion and a web portion. By measuring the radiant energy of the temperature measurement surface, when measuring the surface temperature of the temperature measured surface, first, the radiant energy from each surface is measured with a radiation thermometer, the surface other than the temperature measured surface. Based on the measurement result of the radiant energy from the temperature measurement surface, while performing the correction according to the measurement result of the radiant energy from the is there.

[0006]

According to the present invention, for example, the surface temperature of the flange inner surface or the web portion of the profile having the flange portion and the web portion of the H-section steel or the U-shaped channel steel as described above is measured by the radiation thermometer. If it is attempted, it has been found that as a factor that lowers the temperature measurement accuracy, it is affected by the radiant energy from the periphery of the temperature measured surface such as the inner surface of the flange and the web portion. . When radiation of radiant energy also occurs around the temperature-measured surface, this radiant energy is added to the radiant energy of the temperature-measured surface, increasing the temperature measurement error. In particular, when the intensity of such radiant energy around the surface to be temperature-measured is strong, such temperature measurement error becomes larger.

FIG. 1 is a schematic diagram showing the gist of the present invention.

In FIG. 1, as an example, a high temperature H-section steel 1 is an object to be temperature-measured. Also, FIG.
In, the cross section of the H-section steel 1 is shown. The H
The shaped steel 1 is composed of both flange portions 1a and 1b and a web portion 1c between these flange portions.

When it is attempted to measure the surface temperature of the central portion of the H-shaped steel 1 in the width direction of the web portion 1c, as shown in FIG. 1, the surface of the central portion of the web portion 1c in the width direction is measured. A radiation thermometer 12a is arranged above the table.
The radiation thermometer 12a measures the surface temperature of the web portion 1c by measuring the intensity of radiant energy radiated from the web portion 1c.

In such surface temperature measurement, if there is a high-temperature surface facing the surface to be measured at an angle of less than 180 °, the temperature measurement error increases due to the effect of the radiant energy. . For example, in FIG. 1, the radiant energy from the inner surfaces of the flange portions 1a and 1b facing the web portion 1c at an angle of less than 180 ° is affected. This means that radiant energy is transferred between the flange portion 1a and the web portion 1c, between the flange portion 1b and the web portion 1c, or between the flange 1a and the flange portion 1b.
This is because there is mutual thermal interference.

Therefore, when the surface temperature of the web portion 1c is to be measured by its radiant energy, the reflected energy of the radiation from both the flange portions 1a and 1b is also added, resulting in a temperature measurement error. .

The problem of increase in temperature measurement error due to transfer of radiant energy on the surface to be measured is not limited to the surface temperature measurement by the radiation thermometer of the web portion, but is also the flange portion 1a and the flange portion 1b. It also occurs when measuring the surface temperature of such as. Further, not only such H-section steel, but also, for example, channel steel, or even a profile having another shape will occur. That is, regarding a plurality of surfaces facing each other at an angle of less than 180 °, radiant energy is transferred between the surfaces of these surfaces, which causes the same problem.

In the present invention, attention is paid to such a point, and at least one of a plurality of surfaces of a profile having a flange portion and a web portion facing each other at an angle of less than 180 ° is a surface to be temperature-measured. When the temperature is measured by a radiation thermometer, the radiant energy from each of these surfaces is measured. For example, when measuring the surface temperature of the web portion 1c of the H-shaped steel 1 as shown in FIG. 1, not only the radiant energy of the web portion 1c but also the radiant energy of the inner surface of the flange portion 1a and the flange The radiant energy on the inner surface of the portion 1b is also measured.

Further, in the present invention, the measurement result of the radiant energy thus measured for each surface is effectively used to obtain the desired surface temperature of the surface to be measured. That is, the temperature of the temperature-measured surface is obtained based on the measurement result of the radiant energy from the temperature-measured surface while performing the correction according to the measurement result of the radiant energy from the surface other than the temperature-measured surface. I have to.

Therefore, according to the present invention, even if there is another surface facing the surface to be measured at an angle of less than 180 °, the surface temperature of the surface to be measured can be measured more accurately. It is possible.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 2 is a block diagram showing a radiation temperature measuring method according to the first embodiment to which the present invention is applied.

In the first embodiment, the surface temperature of the flange portion 1a of the H-section steel 1 whose cross section is shown in FIG.
The surface temperature of the web portion 1c is measured. In this embodiment, two radiation thermometers 12a, a converter 13, and a form factor calculator 14 are used for such measurement.

First, of the two radiation thermometers 12a in total, one measures the radiation energy J _f from the surface of the flange portion 1a. The other radiation thermometer 12a
Measures the radiant energy J _w from the surface of the web portion 1c. Radiant energy J from these radiation thermometers 12a
The measurement results of _f and J _w are input to the converter 13.

On the other hand, in the form factor calculator 14, data relating to the shape dimension of the H-section steel 1 is input. The form factor calculator 14 calculates the form factor used for the calculation in the converter 13 based on the data thus input.

The converter 13, together with the form factor calculated by the form factor calculator 14 in this manner, has the H
The emissivity ε related to the radiant energy from the shaped steel 1 is input.
The transducer 13, the emissivity inputted Thus epsilon, the form factor, and the radiant energy J _f, with J _w, calculates the flange temperature T _f and web temperature T _w.

The operation of the first embodiment, such as the calculations performed by the converter 13 and the form factor calculator 14 will be described below with reference to FIG.

FIG. 3 is a network diagram of the radiant energy of the H-section steel.

The H-shaped steel 1 of the object to be temperature-measured in this embodiment
The surface temperature T _w of the web portion 1c and the surface temperature T _f of the inner surface of the flange portion 1a are measured, the surfaces of the flange portions 1a and 1b and the web portion 1c are Consider the transfer of radiant energy between the two. At that time, the surface thermal resistance of each surface is calculated as ((1
-Ε) / εA), the space thermal resistance between the radiation potentials is (1 / Am Fmn), both the emissivity of the inner surface of the flange portion 1a and the emissivity of the surface of the web portion 1c are ε, and , The inner surface of the flange portion 1a and the web portion 1c
If the radiant energy of the surface is E _f or E _w , respectively, a network diagram of the radiant energy as shown in FIG. 3 can be drawn.

The parameters in FIG. 3 and in the following description are as follows.

A _f : Area of the flange portion (unit: m ² ) A _w : Area of the web portion (unit: m ² ) E _a : Radiant energy of the atmosphere (unit: W) E _f : Radiant energy of the flange portion (unit: : W) E _w : Radiant energy of web part (unit: W) F _wf : Form factor from web part to flange part (unit: none) F _wa : Form factor from web part to atmosphere (unit: none) F _ff : Form factor from one flange to the other flange (unit: none) F _fw : Form factor from flange to web (unit: none) F _fa : Form factor from flange to atmosphere (unit) : None) J _f : Radiance potential of the flange (unit: W) J _w : Radiation potential of the web (unit: W)

Here, according to Kirchhoff's law, the algebraic sum of the radiant energy flowing into the nodes J _f and J _w becomes zero. Therefore, these nodes J _f and J
_{For w} , the following equations hold.

Regarding J _f : (E _fav −J _f ) / {(1−ε) / εA _f } + (J _wav −J _f ) / (1 / A _f F _fw ) + (E _aav −J _f ). / (1 / A _f F _fa ) = 0 (1)

Regarding J _w : (E _wav −J _w ) / {(1-ε) / εA _w } + (J _fav −J _w ) / (1 / A _w F _wf ) + (J _fav −J _w ). / (1 / A _w F _wf ) + (E _aav −J _w ) / (1 / A _w F _wa ) = 0 (2)

In the above two equations, E_fav, E
_wav, E_aav, J_favAnd J_wavRespectively E_f,
E_w, E_a, J_fAnd J_wThe average of is shown. Where E_f
= E _fav; E_w= E_wav; E_a= E_aav; J_f=
J_fav; J_w= J_wavThen, the node J_fEnergy at
From the balance, the following formula is established.

ΕE _f + (1-ε) F _fw J _w + (1-ε) F _fa E _a = {ε + (1-ε) (F _fw + F _fa )} J _f (3) εE _w + ( 1-ε) F _wf J _f + (1-ε) F _wa E _a = {ε + (1-ε) (F _wf + F _wa )} J _w (4)

By rearranging the above equations (3) and (4) for J _w , the following equation can be obtained.

J _w = {R _ww E _w + R _wf E _f + R _wa E _a } / R _j (5)

However, in the above equation (5), it is as follows.

R _ww = ε {ε + (1-ε) (F _fw + F _fa )} (6a) R _wf = ε (1-ε) F _wf (6b) R _wa = (1-ε) × { _{εF wa + (1-ε)} [F wa (F fw + F fa) + F wf F fa]} ... (6c) R j = {ε + (1-ε) (F wf + F wa)} × {ε + (1- ε) (F _fw + F _fa )}-(1-ε) ² F _wf F _fw (6d)

On the other hand, when the above equations (3) and (4) are arranged for J _f , the following equation is obtained.

J _f = {R _ff E _f + R _fw E _w + R _fa E _a } / R _j (7)

However, the equation (7) is as follows.

R _ff = ε {ε + (1-ε) (F _wf + F _wa )} (8a) R _fw = ε (1-ε) F _fw (8b) R _fa = (1-ε) × { εF _fa + (1-ε) [F _fa (F _wf + F _wa ) + F _fw F _wa ]} (8c) R _j = {ε + (1-ε) (F _fw + F _fa )} × {ε + (1- ε) (F _wf + F _wa )}-(1-ε) ² F _fw F _wf (8d)

The following relationships can be obtained by the above calculations, particularly the above equations (5) and (7).

R _j J _w = R _ww E _w + R _wf E _f + R _wa E _a (9) R _j J _f = R _fw E _w + R _ff E _f + R _fa E _a (10)

Where J_fAnd J_wIs the hula
Measured with the radiation thermometer 12a at the sensor section or web section.
It is the apparent radiant energy that is determined. On the other hand, E_fPassing
And E _wAre attached to the flange or web, respectively.
It is the true radiant energy.

Further, R _ff , R _fw , R _fa , R _ww , R _wf , R _wa
And R _j are obtained from the emissivity ε and the view factor. Here, the view factor is the surface shape of the temperature measured object,
That is, it is obtained from the shape of the H-section steel 1, and in the present embodiment, it is obtained by the form factor calculator 14 according to the input dimensions of the H-section steel. On the other hand, the emissivity ε is a parameter obtained from the H-section steel 1 which is an object to be temperature-measured, and the converter 13
I am trying to type in.

Note that E _a is the radiant energy of the atmosphere obtained from the atmospheric temperature. In this embodiment, 3
The radiant energy of the atmosphere at 0 ° C. is stored in the converter 13 as a constant.

In the present embodiment, the converter 13
In equation (9) and equation (10), a total of 2
The true radiant energy E _f of the flange portion and the true radiant energy E _w of the web portion are obtained based on the radiation potentials J _f and J _w , which are the apparent radiant energy obtained from each of the radiation thermometers 12a of the table. I am trying.

Further, in this embodiment, the converter 1
3, the surface temperature T _{f of the} flange portion is calculated based on the true radiant energies E _f and E _w thus obtained.
Also, the surface temperature T _w of the web portion is determined.
That is, it is possible to obtain the following relationship, according to Wien's displacement law, in the present embodiment, based on such a relationship, the surface temperature T _f and by the radiant energy E _f and E _w I _try to find T _w .

E _f = (2C ₁ / λ ⁵ ) exp (−C ₂ / (λT _f )) (11) E _w = (2C ₁ / λ ⁵ ) exp (−C ₂ / (λT _w )) ... (12)

Here, C ₁ is Planck's first constant, and C ₂ is Planck's second constant. Further, λ is a measurement wavelength.

As described above, according to the first embodiment, both the flange portions 1a and 1b and the web portion 1 are provided.
In consideration of the effect of the transfer of radiant energy occurring between c and c, the flange temperature T _f and the web temperature T _w can be calculated more accurately while using the two radiation thermometers 12a in total as described above. You can measure.

FIG. 4 is a block diagram showing a radiation temperature measuring method of the second embodiment to which the present invention is applied.

In this embodiment, the radiation potentials J _f and J _w are measured by using one scanning radiation thermometer 12b and the signal processing device 16 in total.

The scanning type radiation thermometer 12b scans the width direction of the H-section steel 1, particularly the inner surface of the flange portion 1a from the upper surface of the web portion 1c to scan the inner surface of the flange portion 1a and the web portion. It is possible to measure the surface temperature at multiple points on the upper surface of 1c. Therefore, by using the scanning radiation thermometer 12b and the signal processing device 16,
It is possible to measure the radiation potential J _f from the inner surface of the flange portion 1a, and further it is possible to measure the radiation potential J _w from the upper surface of the web portion 1c.

Therefore, also in the second embodiment, these radiation potentials J _f and J thus measured are obtained.
Based on _w , the converter 13 similar to that of the first embodiment
By performing the process described above with reference to FIG. 3 using the form factor calculator 14, the flange temperature T _f and the web temperature T _w can be obtained with higher accuracy.

In the first and second embodiments, the H-section steel web temperature correction simulation is performed under the conditions shown in Table 1.

[0055]

[Table 1]

The setting conditions shown in Table 1 are, for example,
The web width W is 400 mm and the flange width H is 400 mm. The condition is that the web temperature T _w is 100 ° C. lower than the flange temperature T _f .

The data obtained under such conditions are shown in FIG.
Is shown in the graph. In FIG. 5, the solid line is according to the first embodiment and the second embodiment. On the other hand, the broken line indicates the conventional method (the one to which the present invention is not applied).

As shown in FIG. 5, in the conventional method shown by the broken line, the measured web portion temperature T _w is
The temperature of the flange portion T _f , which is higher than the above temperature, is affected, and the temperature is higher than that of the first and second embodiments shown by the solid line. For example, about 800 ° C., about 30 ° C. higher, and about 400 ° C., about 20 ° C. higher.

As described above, according to the first embodiment and the second embodiment, for example, the measurement of the web portion temperature T _{w is performed} as follows.
The measurement can be performed while avoiding the influence of the flange temperature T _f . For example, as shown in the graph of FIG. 5, even when the temperature of the flange portions 1a and 1b is higher than that of the web portion 1c by about 100 ° C., the influence of the flange portions 1a and 1b having such a high temperature is affected. By avoiding this, the web portion temperature T _w can be measured more accurately.

In the first and second embodiments, the outer surface of the flange portion 1a and the outer surface of the flange portion 1b are not affected by radiation energy from other parts of the H-section steel 1. Therefore, there is no need to apply the present invention to perform correction due to the influence of radiant energy from other parts.

In the first and second embodiments, when the H-section steel 1 is used as the temperature measurement object,
The web portion 1c is substantially line-symmetrical, and the flange portion 1a and the flange portion 1b are substantially symmetrical. Also, the other conditions such as temperature are the same for the flange portion 1a and the flange portion 1b. Therefore, in these first and second embodiments, the data of the radiation potential J _{f and the} like obtained in the flange portion 1a is also used in the flange portion 1b.

[0062]

As described above, according to the present invention, at least one surface to be temperature-measured among a plurality of surfaces facing each other at an angle of less than 180 ° of a profile having a flange portion and a web portion, By measuring the radiant energy of the temperature measurement surface, it is possible to obtain an excellent effect that a temperature measurement error in measuring the surface temperature of the temperature measurement surface can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing the gist of the present invention.

FIG. 2 is a block diagram showing a radiation temperature measuring method of a first embodiment to which the present invention is applied.

FIG. 3 is a sectional view of an H-section steel showing the measurement principle of the first embodiment.

FIG. 4 is a block diagram showing a radiation temperature measuring method of a second embodiment to which the present invention is applied.

FIG. 5 is a graph showing effects of the first embodiment and the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... H-shaped steel (object to be measured) 1a, 1b ... Flange part 1c ... Web part 12a ... Radiation thermometer 12b ... Scanning radiation thermometer 13 ... Converter 14 ... Form factor calculator 16 ... Signal processing device

Claims (1)

(57) [Claims] 1. A shape member having a flange portion and a web portion.
When measuring the surface temperature of the temperature-measured surface by measuring the radiant energy of the temperature-measured surface of at least one of the plurality of surfaces to be measured facing each other at an angle of less than 80 °, First, the radiant energy from each surface is measured with a radiation thermometer, and the radiant energy from the surface to be measured is corrected while performing the correction according to the measurement result of the radiant energy from the surface other than the surface to be measured. A temperature measuring method for a profile, wherein the temperature of the surface to be measured is determined based on the measurement result of 1.