Technical field
[0001]The present invention, the scale composition determination system, the scale composition determination method, and a program, in particular, is suitable for use to determine the composition of the scale produced on the surface of the steel material.
BACKGROUND
[0002]Steel can scale (coating of iron oxide) on the surface when heated. The scale produced on the surface of the steel material, a single layer scale, there is a multi-layer scale. The single layer scale is a scale consisting of only wustite (FeO). The multilayer scale, hematite (Fe 2 O 3 ), magnetite (Fe 3 O 4 ), and a scale consisting of wustite (FeO). The multilayer scale, from the surface layer, hematite (Fe 2 O 3 ), magnetite (Fe 3 O 4 ), and wustite (FeO) are arranged in this order. As described in Patent Document 1, what will in any scale monolayer scale and multilayer scale, temperature and the steel, defined by the oxygen concentration of the atmosphere around the steel material. The adhesion of the scale is related to its composition. For example, in the hot rolling step, the frequency of occurrence of scale peeling caused by blistering or the like, Fe in the outermost layer of the scale 2 O 3 increased dramatically and is present.
[0003]
　When the scale in the hot rolling step is peeled off, in the subsequent rolling, there is a risk that scratches on the surface of the steel material is formed by peeled scale is pushed into the steel material. Further, even when the peeled scale is not pressed into the steel, there is a risk that after pickling, the patterns of the scale on the surface of the steel occurs. Therefore, to determine the composition of the scale, and the results, it is desirable to make the operation.
[0004]
　As a method for determining the composition of the scale, it can be considered the X-ray diffraction measurement. The X-ray diffraction measurement, to prepare a test piece which scale is to cut the steel has grown to a size of about several cm, to measure the X-ray diffraction pattern of the specimen. Different X-ray diffraction pattern by the crystal structure of the scale is obtained. Therefore, the X-ray diffraction pattern, the outermost layer of the scale Fe 2 O 3 whether there is (i.e., either a single layer scale described above, or a multi-layer scale) can be determined.
[0005]
　However, the X-ray diffraction measurement, it is necessary to prepare a test piece by cutting the steel. Further, it is impossible to measure the X-ray diffraction pattern only after the cold steel. Therefore, it is not possible to determine the composition of the scale that is generated on the surface of the steel material in the operating online (real-time).
[0006]
　Therefore, in the technique described in Patent Document 1, limited process of oxidation in the surface of the steel material, of the steps of the oxygen molecules are supplied to the oxide film on the surface of the steel sheet, the process of the iron atom is oxidized at the surface of the steel material , depending on whether is rate-limiting in any, the outermost layer of the scale Fe 2 O 3 determines whether there is.
CITATION
Patent Document
[0007]
Patent Document 1: JP 2012-93177 JP
Non-patent literature
[0008]
Non-Patent Document 1: Saito Anshun, Omonetakete', Toshio ed translation Maruyama, "high-temperature oxidation of the metal", Uchida Rotsuru圃, p. 32 ~ p. 34, 2013
Summary of the Invention
Problems that the Invention is to Solve
[0009]
　However, in the technique described in Patent Document 1, it is necessary to use a model equation to determine the rate-determining process of oxidation in the surface of the steel material. Therefore, the accuracy of the determination depends on the model equation of accuracy. There is also a need to assume the thickness of the initial oxide layer. Furthermore, it is necessary to set a plurality of model constants in the model equation. Therefore, it is necessary to determine well the model constants accuracy. Therefore, there is a problem that it is not easy to determine in the composition of scale that formed on the surface of the steel material during operation accurately online (real-time).
[0010]
　The present invention has been made in view of the above problems, and an object thereof is to make the composition of scale that formed on the surface of the steel material during operation can be accurately determined online.
Means for Solving the Problems
[0011]
　A first example of the scale composition determination system of the present invention is a scale composition determination system for determining the composition of the scale produced on the surface of the steel material, measuring the radiation temperature of the steel product at two different wavelengths temperature measuring means for measuring by law, on the basis of the difference between the temperature of the steel material measured by the measuring means, the hematite in the outermost layer of the scale (Fe 2 O 3 determination unit configured to determine whether) is generated When have the hematite curve at the first wavelength of the two wavelengths, the thickness of the hematite in the intersection of the hematite curve at the second wavelength, the thickness of the hematite generated in the outermost layer of the scale has been determined to exceed the upper limit of the thickness is assumed as the hematite curve tracks showing the relationship between the temperature of hematite thickness and hematite And characterized in that.
　A second example of the scale composition determination system of the present invention is a scale composition determination system for determining the composition of the scale produced on the surface of the steel material, measuring the radiation temperature of the steel product over N different wavelengths measuring means for measuring the temperature method, based on the difference of the two temperatures of the temperature of the steel material measured by the measuring means, hematite (Fe in the outermost layer of the scale 2 O 3 or) is generated a judging means for judging whether or not the, the N wavelengths, hematite envisaged (Fe 2 O 3Within the thickness of), the N and the intersection all intersect defined as absence of hematite curve at the wavelength, the hematite curve is a curve showing the relationship between the temperature of hematite thickness and hematite There, the N is characterized in that it is an integer of 3 or more.
[0012]
　A first example of the scale composition determination method of the present invention is a scale composition determining method for determining the composition of the scale produced on the surface of the steel material, measuring the radiation temperature of the steel product at two different wavelengths temperature a measurement step of measuring by law, on the basis of the difference between the temperature of the measurement process the steel measured by the hematite in the outermost layer of the scale (Fe 2 O 3 determination step of determining whether or not) has been generated When have the hematite curve at the first wavelength of the two wavelengths, the thickness of the hematite in the intersection of the hematite curve at the second wavelength, the thickness of the hematite generated in the outermost layer of the scale has been determined to exceed the upper limit of the thickness is assumed as the hematite curve is a curve showing the relationship between the temperature of hematite thickness and hematite And wherein the door.
　A second example of the scale composition determination method of the present invention is a scale composition determining method for determining the composition of the scale produced on the surface of the steel material, measuring the radiation temperature of the steel product over N different wavelengths a measuring step of measuring the temperature method, based on the difference of the two temperatures of the temperature of the steel material measured by the measuring step, hematite (Fe in the outermost layer of the scale 2 O 3 or) is generated includes a determination step of determining whether, and the N wavelengths, hematite envisaged (Fe 2 O 3Within the thickness of), the N and the intersection all intersect defined as absence of hematite curve at the wavelength, the hematite curve is a curve showing the relationship between the temperature of hematite thickness and hematite There, the N is characterized in that it is an integer of 3 or more.
[0013]
　The first example of the program of the present invention is a program for executing the determining the composition of the scale produced on the surface of the steel material to a computer, which is measured by the radiation thermometry, mutually different 2 one of the obtaining step of obtaining temperature of the steel material at a wavelength, based on the difference of temperature of the steel material obtained by the obtaining step, hematite (Fe in the outermost layer of the scale 2 O 3 not) has been generated a determination step of determining, cause the computer to execute, the hematite curve at the first wavelength of the two wavelengths, the thickness of the hematite in the intersection of the hematite curve at a second wavelength, the scale top It has been determined to exceed the upper limit of the thickness that is assumed as a thickness of the hematite generated in the surface layer, the hematite curve of hematite Characterized in that it is a curve showing the relationship between the temperature of Mito hematite.
　A second example of the program of the present invention is a program for executing the determining the composition of the scale produced on the surface of the steel material to a computer, which is measured by the radiation thermometry, mutually different N an acquisition step of acquiring the temperature of the steel in the number of wavelengths, based on the difference of the two temperatures of the temperature of the steel material obtained by the obtaining step, hematite (Fe in the outermost layer of the scale 2 O 3 ) is caused to execute a determination step of determining whether or not being generated, to a computer, said N wavelengths, hematite envisaged (Fe 2 O 3Within the thickness of), the N and the intersection all intersect defined as absence of hematite curve at the wavelength, the hematite curve is a curve showing the relationship between the temperature of hematite thickness and hematite There, the N is characterized in that it is an integer of 3 or more.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014]
[1] Figure 1 is a diagram showing an example of a schematic configuration of a hot rolling line.
FIG. 2 is a diagram showing a first example of the configuration of the scale composition determination system.
FIG. 3 is a graph showing the temperature of the steel material, an example of the relationship between the thickness of the single layer scale.
FIG. 4 is a temperature of the steel material, the outermost layer of Fe multilayered scale 2 O 3 is a diagram showing an example of the relationship between the thickness of.
FIG. 5 is, Fe 2 O 3 is a diagram showing time and which are generated, an example of the relationship between the temperature of the steel material.
[6] FIG 6 is a flowchart illustrating an example of an operation of the scale composition determination device.
[7] FIG. 7 is a diagram showing an example of a hardware configuration of the scale composition determination device.
[8] FIG. 8 is a diagram showing a second example of the configuration of the scale composition determination system.
DESCRIPTION OF THE INVENTION
[0015]
　Hereinafter, with reference to the drawings, an embodiment of the present invention.
(First Embodiment)
　First, the first embodiment.

　FIG 1 is a diagram showing an example of a schematic configuration of a hot rolling line is an example of the Apply scale composition determination apparatus 10.
[0016]
　In Figure 1, the hot rolling line includes a heating furnace 11, a descaler 12a ~ 12f, a width direction rolling mill 13, a rough rolling mill 14, and finishing mill 15, a cooling device (ROT) 16, wound preparative and a device (coiler) 17.
　Furnace 11 heats the slab (steel) S.
　Descaler 12a ~ 12f removes the scale that is generated on the surface of the steel material. Scale thickness, for example, 10 [μm] ~ 100 [μm ]. Descaler 12a ~ 12f, for example, by spraying pressurized water on the surface of the steel material, performing descaling (scale removal). Note that the steel is because of its high temperature, even when removing scale steel reoxidation immediately. Therefore, the steel will always be rolled in a state in which the scale is present on the surface.
[0017]
　Width rolling mill 13, rolling the slab S which has been heated in the heating furnace 11 in the width direction.
　Rough rolling mill 14 in the rolling and the crude bar slabs S which is rolled in the width direction in the width direction rolling mill 13 in the vertical direction. In the example shown in FIG. 1, the rough rolling machine 14 includes a roll stand 14a consisting only of the work rolls and a rolling stand 14b ~ 14e having a work roll and the backup roll.
[0018]
　Finishing mill 15, a coarse bar produced by the roughing mill 14 continuously until further predetermined thickness performing hot finish rolling. In the example shown in FIG. 1, finishing mill 15 has seven rolling stands 15a ~ 15 g.
　Cooling device 16, a hot rolled steel sheet H of the hot finish rolling is performed by the finishing mill 15 is cooled by cooling water.
　Winding device 17 winds the hot-rolled steel sheet H, which is cooled by the cooling device 16 into a coil.
[0019]
　Incidentally, hot rolling line can be realized by a known technique, it is not limited to the configuration shown in FIG. For example, of the seven rolling stands 15a ~ 15 g of the finishing mill 15, between the rolling stands upstream (e.g., rolling stands 15a, and between the rolling stands 15b of 15b, 15c between) be arranged descaler to good.
[0020]
　In the present embodiment, with respect to hot rolling line, at least one place a set of radiation thermometer of the two radiation thermometers a set. Radiation thermometer, by radiation thermometry, for measuring the temperature of the steel in a non-contact.
[0021]
　In the example shown in FIG. 1 shows the case of arranging the descaler 12b, regions with a set of radiation thermometer 20a between the rolling stand 14b, and 20b. Rolling stand 14b is a rolling stand provided on the most upstream among the roll stands having a work roll and the backup roll.
　Scale composition determination device 10 shown in FIG. 2, inputs the temperature of the steel material SM measured by a radiation thermometer 20a, 20b. Scale composition determination device 10 based on the temperature of the steel material SM entered, determines the surface of the steel material SM, whether any of the scale SC monolayer scale and multilayer scales are generated. As described above, a single layer scale is a scale consisting of only FeO. Multilayer scale, hematite (Fe 2 O 3 ), magnetite (Fe 3 O 4 ), and a scale consisting of wustite (FeO). The multilayer scale, from the surface layer, hematite (Fe 2 O 3 ), magnetite (Fe 3 O 4 ), and wustite (FeO), are arranged in this order.
[0022]
　Figure 2 is a diagram showing an example of the configuration of the scale composition determination system. In Figure 2, showing the radiation thermometer 20a, and the arrangement of 20b, and an example of the functional configuration of the scale composition determination apparatus 10.

　First, a radiation thermometer 20a, an example of the arrangement of 20b will be described. In Figure 2, shows a case where the direction of the arrows are denoted beside the steel SM is the conveying direction of the steel material SM as an example. Further, the surface of the steel material SM is intended to scale SC is generated.
[0023]
　In Figure 2, the radiation thermometer 20a, 20b of the shaft (the optical axis of the light receiving lenses), as intersection of the passage position of the steel material SM (surface) substantially coincides, disposing a radiation thermometer 20a, and 20b. Incidentally, shown by way in FIG. 2, the radiation thermometer 20a in the conveyance direction of the steel material SM, a case of arranging 20b as an example. However, the radiation thermometer 20a, and 20b of the shaft (the optical axis of the light receiving lens), if as the intersection between a passing position of the steel material SM (surface) substantially coincides, the radiation thermometer 20a, and 20b thus it is not necessary to be placed in. For example, the width direction in the radiation thermometer 20a of the steel material SM, may be arranged to 20b.
[0024]
　Next, an example of a wavelength for detecting radiation thermometer 20a, at 20b.
　Radiation thermometer 20a, in the region (atmosphere) between 20b and a steel SM, steam (H 2 O) and carbon dioxide (CO 2 is a gas such as). The light (infrared) emitted from the scale SC, by the gas, there is absorbed wavelength band.
[0025]
　The present inventors have found that in an environment of hot rolling process was investigated and whether the attenuation of the radiation in the optical path from the measurement target to a radiation thermometer, the relationship between the wavelength λ to be detected by the radiation thermometer. As a result, the present inventors have found that a radiation thermometer 20a, the wavelength λ to be detected by 20b, by selecting from among any of the wavelength bands below (a1) ~ (c1), a radiation thermometer 20a, 20b are , it was confirmed that it is possible to measure the spectral radiance without greatly influenced by the gas in the atmosphere. That is, (a1) 0.6 [μm] ~ 1.6 [μm], (b1) 3.3 [μm] ~ 5.0 [μm], and (c1) 8.0 [μm] ~ 14.0 from the wavelength band of [[mu] m], to select a wavelength λ to be detected by the radiation thermometer 20a, 20b. Thus, the radiation thermometer 20a, 20b can measure the spectral radiance without greatly influenced by the gas in the atmosphere. Incidentally, the spectral radiance at a wavelength lambda [[mu] m], per unit wavelength, per unit area, the radiant flux per unit solid angle [W · [mu] m -1 · sr -1 · m -2 is. Further, the radiation thermometer 20a, the wavelength λ of detecting each 20b shall be chosen from different wavelength bands from each other. For example, if you select the wavelength λ to be measured by the radiation thermometer 20a from the wavelength band of (a1), to select the wavelength λ to be measured by a radiation thermometer 20b from either (b1) or (c1).
[0026]
　Here, the lower limit of the above-mentioned (a1), determined from the lower limit value of the spectral emission wavelength capable luminance measuring the λ the radiation thermometer (the lower limit of the temperature of the steel material SM to be measured). The lower limit of the spectral radiance wavelength capable of measuring the λ is determined according to the temperature of the steel material SM to be measured. For example, when the measures a 900 [° C.] or higher temperatures as the temperature of the steel material SM to be measured, the lower limit is 0.6 [[mu] m wavelength capable of measuring spectral radiance λ the radiation thermometer ]become. Therefore, here, it was 0.6 [[mu] m] the lower limit of (a1). In the case where the lower limit of the temperature of the steel material SM to be measured to 600 [° C.], the lower limit value of the aforementioned (a1) becomes 0.9 [μm]. Further, the upper limit of (c1), determined from constraints of the performance of the optical sensing device of the radiation thermometer (infrared detection capability of long wavelength).
[0027]
　Then, the present inventors have found that in the wavelength λ belonging to the wavelength band of the above-mentioned (a1) ~ (c1), the following studies were made.
　Figure 3 is a graph showing the measured value of the temperature of the steel material SM, an example of the relationship between the thickness of the single layer scale. As shown in FIG. 3, where the temperature is considered as an example steel SM of 900 [° C.].
[0028]
　As shown in FIG. 3, the spectral emissivity ε of FeO in accordance with the wavelength lambda w by the setting a radiation thermometer, a temperature of the single layer scale (FeO), regardless of the thickness of the single layer scale (FeO) constant temperature is measured by a radiation thermometer can be seen that as the measurement value. Further, regardless of the wavelength lambda, the temperature of the single layer scale (FeO), the temperature of the same value is found to be measured by a radiation thermometer. This, FeO is opaque, because there is never the spectral emissivity varies with the thickness. Incidentally, the spectral emissivity ε of FeO w is or measured experimentally, can be determined by or with reference to optical constants database.
[0029]
　Further, the present inventors have found that the temperature of the steel SM having multilayer scale on the surface, the outermost layer of Fe in the multilayered scale 2 O 3 the relationship between the thickness of, (a1), (b1) , (c1 ) was investigated in each wavelength λ belonging to each of the wavelength bands. As described above, the wavelength lambda, the wavelength to be detected by the radiation thermometer.
　At each wavelength lambda, the measured value of the temperature of the steel SM having multilayer scale on the surface, the outermost layer of Fe in the multilayered scale 2 O 3 shows an example of the relationship between the thickness of the Fig. As described above, the outermost layer of the multilayer scale, Fe 2 O 3 is present. In FIG. 4, Fe 2 O 3 and the thickness, the outermost layer of Fe multilayered scale 2 O 3 refers to the thickness of the. Further, in deriving the temperature of the steel material at each wavelength lambda is the spectral emissivity ε of FeO described above in the wavelength lambda w was used.
[0030]
　4, curves 401, 402 and 403 wavelengths λ, respectively (a1), (b1), the wavelength when the band belonging, the measured value of the temperature of the steel material SM, Fe of (c1) 2 O 3 thickness (outermost layer of Fe multilayered scale 2 O 3 shows the relationship between the thickness of). In the present embodiment, thus, at each wavelength lambda, measurements and hematite temperature of the steel material SM (Fe 2 O 3 optionally a curve showing the relationship between the thickness) is referred to as "hematite curve".　
[0031]
　As shown in FIG. 4, values measured with a radiation thermometer of the temperature of the steel material SM having multilayer scale on the surface, Fe 2 O 3 varies by the thickness of. This, Fe 2 O 3 due to the influence of interference of light due to, Fe 2 O 3 by the thickness of, Fe 2 O 3 spectral emissivity of changes, also the waveform (spectral emissivity and Fe 2 O 3 thickness waveform) indicating a relationship between a well, presumably because different depending on the wavelength lambda. Incidentally, Fe 2 O 3 due to the influence of interference of light due to, Fe 2 O 3 by the thickness of, Fe 2 O 3 is the phenomenon itself that the spectral emissivity of the changes is described in Patent Document 1. In the present embodiment, Fe 2 O 3Change in the spectral emissivity due to the thickness of utilizing novel finding that different depending on the wavelength.
[0032]
　From the results shown in FIG. 4, Fe 2 O 3 when the thickness of at least 1.5 [[mu] m] or less, it can be seen that hematite curves 401, 402, 403 all never intersect at one point. Therefore Fe 2 O 3 when the thickness is at least 1.5 [[mu] m] The following is a set of two curves of hematite curve 401, a set of two curves do not intersect with each other at least one exists. Specifically from 4, it can be seen that the following (a2) ~ (c2).
[0033]
　(A2) Fe 2 O 3 when the thickness of the 1.5 [[mu] m] or less, do not intersect and the hematite curves 401 and hematite curve 403.
　(B2) Fe 2 O 3 when the thickness is less than 0.86 [[mu] m], not intersect and the hematite curves 401 and hematite curve 402, and do not intersect and the hematite curves 401 and hematite curve 403.
　(C2) Fe 2 O 3 when the thickness of less than 0.29 [μm], does not intersect any of the hematite curves 401-403.
[0034]
　Incidentally, Fe is produced in the outermost layer of the scale SC 2 O 3 thickness is determined as follows. First, by using the temperature and the subsequent elapsed time of the steel material SM during descaling by descaling, finding a total thickness of the scale SC from known scale thickness calculation formula. Scale thickness calculation formula is an equation for obtaining the total thickness of the scale SC from a function of temperature and time. Then, Fe be generated in the hot-rolling line is assumed 2 O 3 as a thickness of, determine the thickness of 1 [%] of the total thickness of the scale SC. In the present embodiment, in this way, Fe 2 O 3 is described as an example when the thickness of the is estimated. In the following description, Fe is estimated in this way 2 O 3 Fe thickness of optionally 2 O 3 referred estimated thickness. Incidentally, by performing actual lab experiments assumed scale formation temperature history, Fe 2 O 3 may be obtained estimation thickness. The range of the temperature of the steel SM which assumes that in the present embodiment (600 [℃] ~ 1200 [ ℃]), Fe is produced in the outermost layer of the scale SC 2O 3 estimation thickness is thicker by 0.50 [μm]. In steel SM of passing through the finishing mill 15, Fe is produced in the outermost layer of the scale SC 2 O 3 thickness is thicker by 0.18 [μm].
[0035]
　In the range of temperature of the steel SM which assumes that in the present embodiment (600 [℃] ~ 1200 [ ℃]), or more "Fe 2 O 3 and estimate the thickness of the combination of the two hematite curves do not intersect with each other shows the relationship "(a2) ~ (c2) was similar in other combinations of wavelengths of the wavelength band of the above-mentioned (a1) ~ (c1). However, in the combination of other wavelengths, the point of intersection of each hematite curves 401, 402, 403, different from the illustrated intersection in FIG. 4 described above, and (a2) ~ (c2).
[0036]
　For example, Fe in the description of the above-mentioned (a2) 2 O 3 is the upper limit of the estimated thickness of the hematite curve (first hematite curve) obtained from the wavelength λ selected from the wavelength band of (a1), ( hematite curve obtained from the wavelength λ selected from the wavelength band of a2) (calculated from the intersection of the second hematite curve).
　Then, Fe 2 O 3 and 1.5 [[mu] m] is an estimated thickness of, among the thickness calculated from the intersection of the first hematite curve and second hematite curve, the larger the thickness of the first of and thickness, the minimum thickness and the second thickness.
[0037]
　If there is a difference between the first thickness and the second thickness is "do not intersect and hematite curves 401 and hematite curve 403 'of the second thickness is smaller thickness (a2) the upper limit in the case It is adopted as.
[0038]
　Similarly, the (b2) "and hematite curves 401 and hematite curve 402 does intersect, does not intersect and the hematite curves 401 and hematite curve 403" upper region (0.86 [μm] in the example shown in FIG. 4) , adopted to calculate the respective hematite curves 401-403 in accordance with the wavelength λ selected.
[0039]
　(C2) of the "do not intersect any of the hematite curves 401-403" Similarly, the region from the intersection of hematite curves 402 and hematite curve 403, the upper limit (0.29 [μm] in the example shown in FIG. 4) it may be determined. In the present embodiment as described above, in the hot rolling line, steel SM ranging in temperature 600 [℃] ~ 1200 [℃ ] is assumed to be conveyed. In such a temperature range, Fe is employed in place of the upper limit 1.5 [[mu] m] in (a2) 2 O 3 thickness will not vary greatly with respect to 1.5 [μm]. (B2) Fe in the description of ~ (c2) 2 O 3 Similarly for the thickness of not vary significantly from the upper and lower limits shown in Figure 4.
[0040]
　From the above, it can be said the following of (a3) ~ (c3).
　(A3) Fe 2 O 3 estimation thickness of (less than or 1.5 as previously described [[mu] m], Fe 1.5 [[mu] m] 2 O 3 a second thickness) of less than, the above-mentioned (a1) and selecting the wavelength λ, one each from the wavelength band of (c1). Thus, when in their wavelength λ there is a difference between the first temperature and the second temperature measured radiation thermometer 20a, by 20b, Fe in the outermost layer of the scale SC 2 O 3 it can be determined that there is, if there is a difference between the first temperature and the second temperature, as shown in FIG. 3 because FeO is in the outermost layer, Fe 2 O 3 can be determined that there is no.
[0041]
　(B3) Fe 2 O 3 estimation thickness of 0.86 [[mu] m] (Fe is employed in place of or 0.86 as previously described [[mu] m] 2 O 3 of less than the thickness of) the above-mentioned ( a1) and selecting a wavelength λ, one each from the wavelength band of (c1), the aforementioned (a1) and the selecting the wavelength λ, one from among the wavelength band of (b1) either to adopt one. Thus, the radiation thermometer 20a in their wavelength lambda, when there is a difference in temperature measured by 20b, the outermost layer of the scale SC Fe 2 O 3 can be determined that there is, if there is no difference , Fe 2 O 3 can be determined that there is no.
[0042]
　(C3) Fe 2 O 3 estimation thickness of 0.29 [[mu] m] (Fe is employed in place of or 0.29 as previously described [[mu] m] 2 O 3 of less than the thickness of) the above-mentioned ( a1) selecting the wavelength λ, one each from among any two wavelength bands of ~ (c1). Thus, the radiation thermometer 20a in their wavelength lambda, when there is a difference in temperature measured by 20b, the outermost layer of the scale SC Fe 2 O 3 can be determined that there is, if there is no difference , Fe 2 O 3 can be determined that there is no.
[0043]
　As described above, Fe as a target of determination 2 O 3 in accordance with the upper limit value of the estimated thickness of the (second thickness), two wavelength bands from the wavelength band of the above-mentioned (a1) ~ (c1) select. Here, the target of the determination Fe 2 O 3 and the upper limit value of the estimated thickness of the scale SC outermost layer of Fe to be generated on the surface of the steel material SM that hot rolling is carried out at a hot rolling line 2 O 3 is the maximum value of the thickness that is assumed as the estimated thickness. Then, (a1) ~ mutually different wavelengths lambda measured (first wavelength lambda and the second wavelength lambda) selected from among the two wavelength bands selected from among the wavelength bands one each of (c1) the wavelength of interest. In this measurement of each wavelength, using the radiation thermometer 20a, 20b, respectively. Then, it sets the spectral emissivity of FeO at a wavelength λ selected radiation thermometer 20a, to 20b. In this way, constitute radiation thermometer 20a, the 20b. Then, the measured values of the steel temperature measured by the radiation thermometer 20a corresponding to the first wavelength (first steel temperature), the measurement of the steel temperature measured by the radiation thermometer 20b corresponding to the second wavelength if there is a difference between the value (second steel temperature), Fe as the outermost layer of the scale SM being generated on the surface of the steel material SM 2 O 3 is determined to have been generated. In contrast, if there is a difference between the first steel temperature and a second steel material temperature, the outermost layer of the scale SC is FeO, Fe 2 O 3 can be determined to be not generated.
[0044]
　However, in the actual radiation thermometer, the measurement (there tolerance etc.) variations occur because, even outermost layer FeO scale SC, first steel temperature and the second steel material temperature perfectly matched there is a case in which not. Thus, the radiation thermometer 20a, if the absolute value of the difference between the first steel temperature and the second steel material temperature is above a predetermined value measured by 20b, the scale SM being generated on the surface of the steel material SM Fe in the outermost layer 2 O 3 determines that has been generated, otherwise, Fe 2 O 3 preferably determined is not generated. For example, if the variation in temperature is ± 10 [° C.], can be employed 20 [° C.] as the absolute value of the difference between the first steel temperature and a second steel material temperature.
[0045]
　5, Fe 2 O 3 is a diagram showing time and which are generated, an example of the relationship between the temperature of the steel material SM.
　Temperature in Figure 5 shows the temperature of the steel material SM when it is descaled. Here, the temperature of the steel material SM when being de-scaling 1000 [℃], 1050 [℃ ], 1100 [℃], 1150 [℃], at 1200 [° C.], after performing descaling, the steel the outermost layer of Fe of the scale SC that is generated SM surface of 2 O 3 thickness were respectively derived time until 1.5 [μm]. Its value is a plot shown in FIG. Incidentally, the formula used for the derivation, because it is described in Non-Patent Document 1, here, detailed description thereof is omitted. Further, here, Fe 2 O 3 thickness was assumed to be 1 [%] of the thickness of the scale SC.
[0046]
　After performing descaling Fe is produced in the outermost layer of the scale SC 2 O 3 the time until the thickness of is 1.5 [[mu] m] t B and [second], is approximated by a cubic equation, the following (1) becomes formula. Here, T s is the temperature of the steel material SM [° C.].
　t B = -2.978 × 10 -5 × T s 3 + 1.069 × 10 -1 × T s 2 -1.281 × 10 2 × T s + 5.128 × 10 4　· · · (1)
[0047]
　Figure 4 as described with reference to, Fe 2 O 3 if the estimated thickness is 1.5 [[mu] m] or less, as described above, a radiation thermometer 20a, and the wavelength λ to be detected by 20b, radiation thermometer 20a, by determining the spectral emissivity is set to 20b, the outermost layer of the scale SC Fe 2 O 3 can determine whether is generated (the aforementioned (a3) ~ (c3) see). Then, in the actual hot rolling process, the time interval for de-scaling is performed, the time t shown in equation (1) B is often carried out in a shorter time than. Thus, Fe in the outermost layer of the scale SC in the manner previously described 2 O 3 the method determines whether is generated, among the hot rolling line, the time interval at which the descaling is performed, (1) time t shown in B can be applied to the shorter portion than.
[0048]
　However, in the steel material SM being transported to the downstream side of the finishing mill 15, and the temperature is low, since a being continuous rolling, and the cooling water is sprayed, the outermost layer of the scale SC Fe produced 2 O 3 thickness is thicker by 0.1 [μm]. Thus, in the downstream side of the finishing mill 15, (1) the time t shown in equation B independently of the can determine where to place the radiation thermometer 20a, and 20b.
[0049]

　Next, an example of details of the scale composition determination apparatus 10. Hardware scale composition determination device 10 includes, for example, it can be realized CPU, ROM, RAM, HDD, and an information processing apparatus provided with various interfaces, or by using a dedicated hardware.
[0050]
　Figure 6 is a flowchart illustrating an example of an operation of the scale composition determination apparatus 10. With reference to FIGS. 2 and 6, an example of a function of the scale composition determination apparatus 10. The flowchart of FIG 6 is performed every time the temperature of the steel material SM is measured radiation thermometer 20a, by 20b.
[0051]
　In step S601, the temperature acquiring unit 201 acquires the temperature of the steel material SM measured by a radiation thermometer 20a, 20b.
　Next, in step S602, the determination unit 202, the absolute value of the difference between the temperature of the obtained steel SM at step S601 is equal to or higher than a predetermined temperature. Predetermined temperature, before starting the execution of the flowchart of FIG. 6, is set to the scale composition determination device 10. Further, as described above, for example, when the variations of temperature is ± 10 [° C.], can be employed 20 [° C.] as a predetermined value.
[0052]
　The result of this determination, if the absolute value of the difference between the temperature of the steel material SM is equal to or greater than a predetermined temperature, Fe in the outermost layer of the scale SC 2 O 3 is judged to be generated (i.e., steel SM multilayer scale is determined to be generated on the surface). Therefore, in step S603, the output unit 203, Fe in the outermost layer of the scale SC 2 O 3 outputs information indicating that has been generated (multilayer scale on the surface of the steel material SM is generated). Then, the processing according to the flowchart of FIG.
[0053]
　On the other hand, when the absolute value of the difference between the temperature of the steel material SM is less than the predetermined temperature, Fe in the outermost layer of the scale SC 2 O 3 is determined not to be generated (i.e., single layer on the surface of the steel material SM scale is determined to be generated). Therefore, in step S604, the output unit 203, the outermost layer of the scale SC Fe 2 O 3 outputs information indicating that the has not been generated (monolayer scale on the surface of the steel material SM is generated). Then, the processing according to the flowchart of FIG.
[0054]
　As the output form of the information by the output unit 203, for example, display on a computer display, transmission to an external device, and at least one of storage in the internal or external storage medium of the scale composition determination device 10 it can be adopted.
[0055]
　Figure 7 is a diagram showing an example of a hardware configuration of the scale composition determination apparatus 10.
　7, the scale composition determination device 10, CPU 701, main memory 702, an auxiliary storage device 703, a communication circuit 704, the signal processing circuit 705, image processing circuit 706, I / F circuit 707, a user interface 708, a display 709, and a bus 710.
[0056]
　CPU701 performs overall control of the entire scale composition determination apparatus 10. CPU701, using the main memory 702 as a work area, executes a program stored in the auxiliary storage device 703. Main memory 702 stores data temporarily. The auxiliary storage device 703, other program executed by the CPU 701, stores various data. The auxiliary storage device 703 stores information necessary for processing of the flowchart shown predetermined temperature such as mentioned above, in FIG.
[0057]
　The communication circuit 704 is a circuit for communicating with an external scale composition determination apparatus 10.
　The signal processing circuit 705, the signal and received by the communication circuit 704, the input signal under the control of the CPU 701, performs various signal processing. Temperature acquisition unit 201, for example, CPU 701, to perform its function by using the communication circuit 704 and the signal processing circuit 705. The determination unit 202, for example, exerts its function by using the CPU701 and the signal processing circuit 705.
[0058]
　The image processing circuit 706, the input signal under the control of the CPU 701, performs various image processing. Signal the image processing has been performed is output to the display 709.
　The user interface 708 is a portion that the operator gives an instruction to the scale composition determination device 10. The user interface 708 has, for example, buttons, switches, and a dial or the like. The user interface 708 may have a graphical user interface using a display 709.
[0059]
　Display 709 displays an image based on the signal outputted from the image processing circuit 706. I / F circuit 707 exchanges data with the devices connected to the I / F circuit 707. In Figure 7, a device connected to the I / F circuit 707, showing the user interface 708 and display 709. However, devices connected to the I / F circuit 707 is not limited thereto. For example, portable storage medium may be connected to the I / F circuit 707. At least a portion and a display 709 of the user interface 708 may be external to the scale composition determination apparatus 10.
　The output unit 203 is, for example, exert a communication circuit 704 and the signal processing circuit 705, image processing circuit 706, I / F circuit 707, and the function by using at least one of the display 709.
[0060]
　Incidentally, CPU 701, main memory 702, an auxiliary storage device 703, the signal processing circuit 705, image processing circuit 706 and the I / F circuit 707, is connected to the bus 710. Communication between these components is performed via the bus 710. The hardware of the scale composition determination device 10, if it is possible to realize the function of the scale composition determination apparatus 10 described above is not limited to that shown in FIG.
[0061]
　In this embodiment as described above, the scale composition determination device 10, when the absolute value of the difference between the temperature of the steel material SM measured radiation thermometer 20a, by 20b is equal to or greater than a predetermined temperature, the outermost layer of the scale SC the Fe 2 O 3 is determined as is generated, otherwise, Fe in the outermost layer of the scale SC 2 O 3 determines that is not generated. At that time, a radiation thermometer 20a, for each of the selected wavelength λ from the wavelength band which is not affected by the gas in the atmosphere as measured by 20b, previously obtained hematite curve beforehand. In the present embodiment, hematite curve, the temperature of the steel material SM to be measured by a radiation thermometer was set spectral emissivity of FeO (Fe 2 O 3 and temperature), Fe 2 O 3 curve showing the relationship between the thickness of the it is. Then, Fe being measured 2 O 3 the upper limit of the thickness of, Fe at the intersection of the curves 2 O 3Obtaining a set of wavelength λ such that less than thickness. The radiation thermometer 20a, the wavelength to be detected by 20b lambda, the radiation thermometer 20a, the spectral emissivity is set to 20b, respectively, determined wavelength lambda, the spectral emissivity of FeO in the wavelength lambda. Therefore, by performing the two radiation thermometry can scale SC that is generated on the surface of the steel material SM in operation is to determine accurately whether the multilayer scale or a single layer scale online. Thus, for example, or you can go to quickly and accurately manage the operations, or quickly as and accurately reflected in the operation of the discrimination result of the composition of the scale SC.
[0062]

[Modification 1]
　In the present embodiment was described by taking two radiation thermometers 20a, a case of using 20b as an example. However, if so as to measure the temperature by radiation thermometry at two different wavelengths, it is not limited to this. For example, it may be a single radiation thermometer with a part of the optical system in two-color thermometer. Specifically, for example, disperses light entering from the same light receiving lens into two by the half mirror. Then, the light spectrally, through either one of the two wavelength selective filter which passes only light of mutually different wavelengths. Measuring the temperature by radiation thermometry for the light that has passed through the wavelength selection filter. In this way, it is possible to save space of the radiation thermometer.
[0063]
[Modification 2]
　In the present embodiment, descaler 12b and the work roll and the backup roll and the region with a set of radiation thermometer 20a between the rolling stand 14b provided at the most upstream among the roll stands having, 20b the case of arranging the shown as an example. However, the hot rolling process, it if a place downstream of the most upstream descaler 12a (extracted from the heating furnace 11, if the measured temperature of the steel sheet at least one descaling has been performed) , where to place a set of radiation thermometer is not limited to this location. For example, it is possible to arrange a descaler, a location between the rolling stand located closest downstream to the descaler, a set of radiation thermometer. Further, the plurality of locations of such locations, may be disposed a set of radiation thermometer respectively (i.e., may be more disposed pairs of the radiation thermometer). In this case, the scale composition determination device 10, for a set of each radiation thermometer, subjected to a flow chart shown in FIG. 6, at each location where a set of radiation thermometer is disposed, Fe as the outermost layer of the scale SC 2 O 3 determines whether or not it is generated.
[0064]
[Modification 3]
　In the present embodiment, the radiation thermometer 20a, as spectral emissivity is set to 20b, an example in which setting the spectral emissivity of FeO in accordance with the wavelength λ to be detected by the radiation thermometer 20a, 20b It has been described as. However, it is not necessarily need to be the case. For example, radiation thermometers 20a, as spectral emissivity of 20b, may be set to the same value regardless of the wavelength lambda (for example, to 0.78 in any of the wavelength lambda, also or in the initial setting value good). If to such, the inherent FeO spectral emissivity different spectral emissivity of being set in the radiation thermometer 20a, 20b. Accordingly, by that amount, also changes the temperature measured radiation thermometer 20a, by 20b. Therefore, minute in consideration of the change in the temperature, to determine the magnitude of the predetermined value to be compared with the absolute value of the difference between the temperature measured radiation thermometer 20a, by 20b.
[0065]
[Modification 4]
　In the present embodiment has been described as an example a case of applying the scale composition determination device 10 to the hot rolling line of the sheet. However, the Apply scale composition determination device 10 is not limited to the hot rolling line of the sheet. In this case, the content of the wavelength ranges defined in the aforementioned (a1) ~ (c1) will content corresponding to the Apply scale composition determination apparatus 10. Further, Fe 2 O 3 thickness, such as, what is specified in the aforementioned (a3) ~ (c3) also becomes the content corresponding to the application target of the scale composition determination apparatus 10. However, even in this case, as shown by curve 401 and 403 shown in FIG. 4, the temperature of the steel material SM obtained by radiation thermometry at two wavelengths different from each other lambda (Fe 2 O 3 and temperature), Fe 2 O 3 Fe at the intersection of the two curves showing the relationship between the thickness of 2 O 3 thickness of, Fe to be measured 2 O 3 two wavelengths λ that exceeds the upper limit of the thickness of the radiation thermometer 20a , the wavelength λ to be detected by 20b. Other Apply scale composition determination device 10, for example, the heating furnace described in Patent Document 1.
[0066]
[Modification 5]
　In the present embodiment has been described by taking a case of measuring the temperature by a radiation thermometer 20a, 20b as an example. However, it is not always necessary to obtain radiation thermometer 20a, 20b at up to temperature. For example, to detect the spectral radiance by radiometer, the scale composition determination device 10 based on the detected spectral radiance may be the temperature measured (derived). Without risk of damage to the thermometer may be used thermometer contact.
[0067]
(Second Embodiment)
　Next, a second embodiment will be described. In the first embodiment, the two radiation thermometers 20a, a case of using a 20b has been described as an example. In contrast, in the present embodiment, the case of using three or more radiation thermometers. Thus the present embodiment and the first embodiment is different from the that the number of radiation thermometer is different, and a part of the processing of the scale composition determination apparatus 10 according to the number of the radiation thermometer mainly different. Accordingly, in the description of this embodiment, the first embodiment and the same parts of, and detailed description thereof is omitted equal denoted by the same reference numerals as those in FIGS. 1 to 7.
[0068]
　Figure 8 is a diagram showing an example of the configuration of the scale composition determination system. 8 shows the radiation thermometer 20a, 20b, the arrangement of 20c, an example of the functional configuration of the scale composition determination apparatus 10. Figure 8 is a view corresponding to FIG.

　First, a radiation thermometer 20a, 20b, an example of the arrangement of 20c will be described. 8, the radiation thermometer 20a, 20b, and 20c of the shaft (the optical axis of the light receiving lenses), as intersection of the passage position of the steel material SM (surface) substantially coincides, radiation thermometers 20a, 20b, 20c to place. Incidentally, shown by way in FIG. 8, the radiation thermometer 20a in the conveyance direction of the steel material SM, 20b, the case of arranging 20c as an example. However, the radiation thermometer 20a, 20b, and 20c of the shaft (the optical axis of the light receiving lens), if as the intersection between a passing position of the steel material SM (surface) substantially coincides, radiation thermometers 20a, 20b, 20c and need not be arranged in this manner. For example, the width direction in the radiation thermometer 20a of the steel material SM, 20b, may be arranged to 20c.
[0069]
　Then, the radiation thermometer 20a, 20b, an example of a wavelength detected in 20c will be described.
　Radiation thermometer 20a is a radiation thermometer to wavelength to be measured has been a wavelength λ selected from the wavelength band of that described in the first embodiment (a1). Radiation thermometer 20b is a radiation thermometer to wavelength to be measured has been a wavelength λ selected from the wavelength band of that described in the first embodiment (b1). Radiation thermometer 20c is a radiation thermometer to wavelength to be measured has been a wavelength λ selected from the wavelength band of that described in the first embodiment (c1).
[0070]
　Further, the spectral emissivity ε of FeO in accordance with the wavelength lambda w to set the radiation thermometer 20a, 20b, to 20c.
　As described above radiation thermometer 20a, 20b, by using 20c, and the temperature of the steel SM having multilayer scale on the surface, the outermost layer of Fe in the multilayered scale 2 O 3 as an example of the relationship between the thickness of the , can be obtained hematite curve 401 in FIG.
[0071]
　In the example shown in FIG. 4, the outermost layer of Fe multilayered scale 2 O 3 as long as the thickness of 1.5 [[mu] m] or less, the intersection of all the curves 401, 402, 403 intersect is not present. Thus, the radiation thermometer 20a, 20b, of the two of the plurality of combinations of the temperature of the temperature measured by 20c, a difference in temperature in at least one combination occurs. Thus, the radiation thermometer 20a, 20b, of the two of the plurality of combinations of the temperature of the temperature measured by 20c, when there is a difference in temperature in at least one combination, Fe in the outermost layer of the scale SC 2 O 3 it can be determined that there is, if there is no difference in all combinations, Fe 2 O 3 can be determined that there is no. In this way, Fe in the determination target 2 O 3 can expand the range of the estimated thickness of. Further, Fe 2 O 3 by estimating the thickness of, eliminating the need to replace the radiation thermometer.
[0072]
　However, as described in the first embodiment, the actual radiation thermometer (with tolerances) variations in measurements. Thus, the radiation thermometer 20a, 20b, among the plurality of combinations of the two temperatures of the temperature measured by 20c, if the absolute value of the temperature difference in at least one combination or more predetermined values, steel SM Fe in the outermost layer of the scale SM that are generated on the surface 2 O 3 determines that has been generated, otherwise, Fe 2 O 3 preferably determined is not generated. For example, if the variation in temperature is ± 10 [° C.], can be employed 20 [° C.] as a predetermined value.
　Also, portions of placing radiation thermometer 20a, 20b, and 20c are the same as portions described in the first embodiment.
[0073]

　configuration of the scale composition determination device 10 is the same as the scale composition determination device 10 of the first embodiment. With reference to the flowchart of FIG. 6, an example of a function of the scale composition determination apparatus 10 of the present embodiment. The flowchart of FIG. 6, a radiation thermometer 20a, 20b, is executed each time the temperature of the steel material SM is measured by 20c.
[0074]
　In step S601, the temperature acquiring unit 201 acquires a radiation thermometer 20a, 20b, the measured temperature of the steel SM at 20c.
　Next, in step S602, the determination unit 202, among the plurality of combinations of the two temperatures of the temperature of the obtained steel SM at step S601, the absolute value of the predetermined temperature of the temperature difference in at least one combination It determines at either higher.
[0075]
　As a result of this determination, one of two of the plurality of temperature combination of the temperature of the obtained steel SM at step S601, if the absolute value of the temperature difference in at least one combination is equal to or greater than a predetermined temperature, the outermost layer of the scale SC Fe 2 O 3 is judged to be generated (i.e., multilayer scale is determined to be generated on the surface of the steel material SM). Therefore, in step S603, the output unit 203, Fe in the outermost layer of the scale SC 2 O 3 outputs information indicating that has been generated (multilayer scale on the surface of the steel material SM is generated). Then, the processing according to the flowchart of FIG.
[0076]
　On the other hand, among the plurality of combinations of the two temperatures of the temperature of the obtained steel SM at step S601, if the absolute value of the temperature difference in at least one combination is less than the predetermined temperature, most of the scale SC surface Fe in 2 O 3 is determined not to be generated (i.e., single layer scale is determined to be generated on the surface of the steel material SM). Therefore, in step S604, the output unit 203, the outermost layer of the scale SC Fe 2 O 3 outputs information indicating that the has not been generated (monolayer scale on the surface of the steel material SM is generated). Then, the processing according to the flowchart of FIG.
[0077]
　In the example shown in FIG. 4, the intersection of all the curves 401, 402, 403 intersect is not present. However, for example, by the application destination of the scale composition determination device 10, and the temperature of the steel material SM, the outermost layer of Fe in the multilayered scale 2 O 3 intersections intersect three curves showing the relationship between the thickness of the can occur. Therefore, as in the first embodiment, such a point of intersection in advance to ensure that it does not. More specifically, as follows.
[0078]
　A wavelength λ selected from the wavelength band of (a1) a measurement wavelength of the radiation thermometer 20a. Also, setting the spectral emissivity of FeO in accordance with the wavelength λ in the radiation thermometer 20a. A wavelength λ selected from the wavelength band of (b1) a measurement wavelength in the radiation thermometer 20b. Also, setting the spectral emissivity of FeO in accordance with the wavelength λ in the radiation thermometer 20b. A wavelength λ selected from the wavelength band of (c1) as a measurement wavelength in the radiation thermometer 20c. Also, setting the spectral emissivity of FeO in accordance with the wavelength λ in the radiation thermometer 20c.
[0079]
　Or more radiation thermometers 20a, 20b, the temperature of the steel material SM (Fe measured at 20c 2 O 3 and temperature), Fe 2 O 3 to create each hematite curve showing the relationship between the estimated thickness. Then, Fe 2 O 3 within the range of the estimated thickness of, determines whether there is an intersection that intersects three hematite curves. If there is an intersection where three hematite curves intersect changes at least one of the measuring wavelength in the radiation thermometer 20a, 20b, 20c. Then, in the same manner as described above, Fe 2 O 3 determines whether within the estimated thickness, there is a point of intersection intersect three hematite curves. The above steps, Fe 2 O 3 within the range of the estimated thickness of the performed until no intersection intersecting three hematite curves. Then, Fe 2 O 3 within the range of the estimated thickness of, if there is no intersection intersect three hematite curves, employing radiation thermometer 20a while writing the three hematite curves, 20b, a measurement wavelength of 20c.
[0080]
　In this embodiment as described above, the scale composition determination apparatus 10, the radiation thermometers 20a, 20b, among the plurality of combinations of the two temperatures of the measured temperature of the steel SM by 20c, in at least one combination If the absolute value of the difference in temperature is equal to or higher than a predetermined temperature, the outermost layer of the scale SC Fe 2 O 3 when determining that has been generated, otherwise, Fe in the outermost layer of the scale SC 2 O 3 It determines that but has not been generated. Therefore, in addition to the effects described in the first embodiment, the following effects can be obtained. That, Fe determination target 2 O 3 can expand the range of the estimated thickness of. Further, Fe is supposed 2 O 3 by estimating the thickness of, it is not necessary to replace the radiation thermometer.
[0081]
　In the first embodiment, the number of radiation thermometer is two. In contrast, in the present embodiment, the number of radiation thermometer is three. Therefore, towards the first embodiment, than in the second embodiment, it can be constructed at low cost system. Further, towards the first embodiment, than in the second embodiment, it can be made compact installation space of the radiation thermometer. On the other hand, in the second embodiment, Fe is supposed 2 O 3 even, the outermost layer of the scale SC Fe when the estimated thickness of is changed 2 O 3 can be reliably determined whether or not there is. For example, it is possible to determine in view of the above, to employ any form of the first embodiment and the second embodiment.
[0082]

[Modification 6]
　In the present embodiment has been described as an example where the number of three wavelengths λ to be detected by the radiation thermometer. However, the number of wavelengths λ to be detected by the radiation thermometer may be at least three. For example, as described in the first embodiment (a1), (b1), and among the wavelength band of (c1), from among the two or more wavelength bands, by selecting the wavelength λ to be detected by the radiation thermometer it may be. However, this time, to select a total of three or more wavelengths. Thus, (a1), it is not necessary to select the wavelength λ from all wavelength bands of (b1), and (c1).
[0083]
　Further, it is the number of wavelengths λ to be detected by the radiation thermometer even if two, adopting the method of this embodiment. In this case, the two temperature of the steel material SM to be measured by a radiation thermometer (Fe 2 O 3 and temperature), Fe 2 O 3 so that all of the two curves showing the relationship between the thickness of intersections intersect absent , to select a wavelength λ to be detected by the two radiation thermometers. In the example shown in FIG. 4, to select the hematite curves 401 and 403 correspond to this. For example, (a1), (b1) , and among the wavelength band of (c1), from among the two wavelength bands, as a wavelength λ to be detected by the radiation thermometer may be selected a total of two wavelengths.
　From the above, (a1), when using a wavelength band of (b1), and (c1), the wavelength λ to be detected by the radiation thermometer, (a1), the wavelength band of (b1), and (c1) among, the wavelengths of the two or more wavelength bands.
[0084]
　Generalizing the above, Fe 2 O 3 within the range of the estimated thickness of the temperature of the steel material SM to be measured by the N radiation thermometer (Fe 2 O 3 and temperature), Fe 2 O 3 thickness as no intersection all intersect exist of N hematite curve showing the relationship between, to select a wavelength to be detected by the N radiation thermometer lambda.
　Specifically, the N wavelengths, the wavelength of the first wavelength to N-th, the wavelength selected, one from the wavelength of the first wavelength to N-th and the wavelength of the n (the n as the wavelength and selecting a wavelength of the first wavelength to N-th one by one). Then, the hematite curve at the wavelength of the n-th, and the thickness of the hematite, spectral emissivity wustite (FeO) with the temperature of the hematite obtained by radiation thermometry at the wavelength of the first n as the spectral emissivity of It becomes curve showing the relationship. Here, the wavelength of the first wavelength to N-th are hematite envisaged (Fe 2 O 3 within the range of the thickness of the) intersection all intersect hematite curve at the wavelength of the first wavelength, second N is present It is defined so that it does not. Then, measured by a radiation temperature measuring method the temperature of the steel material at the wavelength of the n-th spectral emissivity as a spectral emissivity of wustite at the wavelength of the first n. Performed for each such measurement of the wavelength of the first wavelength, second N.
　In the above description, N is the, but preferably an integer of 3 or greater, may be an integer of 2 or more.
[0085]
[Modification 7]
　In the present embodiment, it is possible to adopt a modification described in the first embodiment.
[0086]
[Other Modifications]
　embodiment of The present invention described above can be realized by a computer executing a program. A computer program product such as the programmable read computer recorded the recording medium and the program is also applicable as an embodiment of the present invention. As the recording medium, for example, it may be used a flexible disk, hard disk, optical disk, CD-ROM, magnetic tape, nonvolatile memory card, a ROM or the like.
　Further, embodiments of the present invention described above are all merely illustrate concrete examples of implementing the present invention, the technical scope of the present invention should not be restrictively interpreted it is intended. That is, the present invention without departing from its spirit or essential characteristics thereof, can be implemented in various forms.
Industrial Applicability
[0087]
　The present invention can be utilized such as to produce a steel material.

The scope of the claims

[Requested item 1]A scale composition determination system for determining the composition of the scale produced on the surface of the steel material,
　and measuring means for measuring the measured radiation temperature of the steel product at two different wavelengths temperature method,
　measured by the measuring means was based on the difference of temperature of the steel material, the hematite in the outermost layer of the scale (Fe 2 O 3 has a determining means for determining whether) is generated,
　the first of said two wavelengths and hematite curve at the wavelength of the thickness of the hematite in the intersection of the hematite curve at the second wavelength, determined as the upper limit of the thickness that is assumed as a thickness of the hematite generated in the outermost layer of the scale and which,
　the hematite curve, the scale composition determination system which is a curve showing the relationship between the temperature of hematite thickness and hematite .
[Requested item 2]
　The hematite curve at the first wavelength, a thickness of the hematite, spectral emissivity relation between the temperature of hematite obtained by radiation thermometry at the first wavelength as the spectral emissivity of wustite (FeO) a curve showing,
　the hematite curve at the second wavelength is obtained and the thickness of the hematite, with warm method measuring radiation at the second wavelength as the spectral emissivity of the spectral emissivity of wustite (FeO) is a curve showing the relationship between the temperature of hematite,
　said measuring means measures the radiation thermometry temperature of the steel in the first wavelength spectral emissivity as a spectral emissivity of wustite in the first wavelength it and radiation thermometry temperature of the steel in the second wavelength spectral emissivity as a spectral emissivity of wustite in the second wavelength Scale composition determination system according to claim 1, characterized in that a be more measured.
[Requested item 3]
　The determination unit, when the absolute value of the difference between the temperature of the steel material measured by the measuring means is a predetermined value or more, determines that the hematite in the outermost layer of the scale has been generated, otherwise the scale composition determination system according to claim 1 or 2, characterized in that to determine that hematite is not generated in the outermost surface layer of the scale.
[Requested item 4]
　The steel to be measured of the temperature, is extracted in a heating furnace in the hot rolling process, and, according to claim 1 to 3, characterized in that a steel material after at least one descaling is performed scale composition determination system according to any one.
[Requested item 5]
　The two wavelengths, the wavelength in the range of 0.6 [μm] ~ 1.6 [μm], and a wavelength in the range of 3.3 [μm] ~ 5.0 [μm], 8.0 [ μm] ~ 14.0 [μm] scale composition determination system according to claim 4, characterized in that any two of wavelength in the range of.
[Requested item 6]
　It said measuring means includes a light receiving lens, a spectroscopic means for spectrally into two light entering through the light receiving lens, extracting means for extracting the light of the two wavelengths from the light dispersed by the spectroscopic means the a scale composition determination according to any one of claims 1 to 5, wherein the measuring the radiation thermometry temperature of the steel in the extracted the two wavelengths by the extraction unit system.
[Requested item 7]
　A scale composition determination system for determining the composition of the scale produced on the surface of the steel material,
　and measuring means for measuring the radiation thermometry temperature of the steel product over N different wavelengths,
　measured by the measuring means based on the difference between the two temperatures of the temperature of the steel material are, hematite the outermost layer (Fe of the scale 2 O 3 has a determining means for determining whether) has been generated,
　the N wavelengths are hematite envisaged (Fe 2 O 3 within the range of the thickness of) the and the intersection all intersect defined as absence of N hematite curve at the wavelength,
　the hematite curve is a curve showing the relationship between the temperature of hematite thickness and hematite,
　wherein N is the scale composition determination system characterized in that it is an integer of 3 or more.
[Requested item 8]
　The N wavelength is the wavelength of the first wavelength to N-th,
　the one at wavelengths selected from the wavelength of the first wavelength to N-th and the wavelength of the n,
　at a wavelength of said first n the hematite curve, the thickness of the hematite is a curve showing the relationship between the temperature of hematite obtained by radiation thermometry at the wavelength of the first n as the spectral emissivity of the spectral emissivity of wustite (FeO),
　said measuring means, the temperature of the steel material at the wavelength of the first n spectral emissivity as a spectral emissivity of wustite at the wavelength of the first n measured by the radiation thermometry,
　the wavelength of the first wavelength, second n is hematite envisaged (Fe 2 O 3 within the range of the thickness of the), and characterized in that the intersection all intersect hematite curve at the wavelength of the first wavelength, second N is defined such that there to claim 7, serial Scale composition determination system of.
[Requested item 9]
　The determination means of the two temperature combination of one of the said steel measured by the measuring means temperature, when the absolute value of the temperature difference in at least one combination is a predetermined value or more, the scale outermost surface layer determines that hematite is generated, otherwise, the scale composition determination according to claim 7 or 8, wherein determining that no hematite is generated in the outermost surface layer of the scale of system.
[Requested item 10]
　The steel to be measured of the temperature, is extracted in a heating furnace in the hot rolling process, and, according to claim 7-9, characterized in that a steel material after at least one descaling is performed scale composition determination system according to any one.
[Requested item 11]
　Said N wavelengths, the wavelength in the range of 0.6 [μm] ~ 1.6 [μm], and a wavelength in the range of 3.3 [μm] ~ 5.0 [μm], 8.0 [μm] ~ 14.0 [μm] scale composition determination system according to claim 10, characterized in that of the wavelength is the wavelength in any two or more ranges within the range of.
[Requested item 12]
　It said measuring means includes a light receiving lens, a spectroscopic means for spectrally separating light entering into N through the light receiving lens, extracting means for extracting the light of the N wavelengths from the spectral light by the spectroscopic means When having a scale according to any one of claims 7 to 11, characterized by measuring the radiation thermometry temperature of the steel in the extracted the N wavelengths by the extraction unit The composition determining system.
[Requested item 13]
　Wherein N is the scale composition determination system according to any one of claims 7 to 12, characterized in that an integer of 3 or more.
[Requested item 14]
　A scale composition determining method for determining the composition of the scale produced on the surface of the steel material,
　the step of measuring the radiation thermometry temperature of the steel product at two different wavelengths,
　measured by the measuring step was based on the difference of temperature of the steel, hematite (Fe in the outermost layer of the scale 2 O 3 anda determination step of determining whether) is generated,
　the first of said two wavelengths and hematite curve at the wavelength of the thickness of the hematite in the intersection of the hematite curve at the second wavelength, determined as the upper limit of the thickness that is assumed as a thickness of the hematite generated in the outermost layer of the scale and which,
　the hematite curve, the scale composition determination method which is a curve showing the relationship between the temperature of hematite thickness and hematite.
[Requested item 15]
　A scale composition determining method for determining the composition of the scale produced on the surface of the steel material,
　the step of measuring by mutually N different radiation thermometry temperature of the steel material at a wavelength,
　measured by the measuring step based on the difference between the two temperatures of the temperature of the steel material are, hematite the outermost layer (Fe of the scale 2 O 3 anda determination step of determining whether) has been generated,
　the N wavelengths are hematite envisaged (Fe 2 O 3 within the range of the thickness of) the and the intersection all intersect defined as absence of N hematite curve at the wavelength,
　the hematite curve is a curve showing the relationship between the hematite thickness and hematite temperature,
　the N is the scale composition determination method, characterized in that it is an integer of 3 or more.
[Requested item 16]
　A program for executing the determining the composition of the scale produced on the surface of the steel material to a computer,
　which is measured by the radiation thermometry, acquires the temperature of the steel product at two different wavelengths get a step,
　based on the difference of temperature of the steel material obtained by the obtaining step, hematite (Fe in the outermost layer of the scale 2 O 3 and a determination step of determining whether) is generated in the computer It is executed,
　and hematite curve at the first wavelength of the two wavelengths, the thickness of the hematite in the intersection of the hematite curve at the second wavelength, is assumed as a thickness of the hematite generated in the outermost layer of the scale that it has been determined as the upper limit of the thickness,
　the hematite curve, the relationship between the temperature of hematite thickness and hematite Program, which is a to the curve.
[Requested item 17]
　A program for executing the determining the composition of the scale produced on the surface of the steel material to a computer,
　which is measured by the radiation thermometry, acquires the temperature of the steel product over N different wavelengths an acquisition step,
　based on the difference of the two temperatures of the temperature of the steel material obtained by the obtaining step, the hematite in the outermost layer of the scale (Fe 2 O 3 determines whether) is generated a determination step, cause the computer to execute,
　the N wavelengths, hematite envisaged (Fe 2 O 3 within the range of the thickness of), there is no intersection all intersect hematite curve at the N wavelengths and-defined by such,
　the hematite curve is a curve showing the relationship between the temperature of hematite thickness and hematite,
　wherein N is up, characterized in that it is an integer of 3 or more Grams.