Steel wire coil conveying equipment

Abstract

The present invention provides a steel wire coil conveying system that enables accurate measurement of the temperature of the dense and coarse parts of the steel wire coil. [Solution] The steel wire coil conveying equipment 1 is provided, comprising a conveyor 2 that conveys steel wire coils 5 along the conveying direction, a two-color radiation thermometer 3 installed above the conveyor 2, and a back plate 4 installed below the conveyor 2, wherein the conveyor 2 is equipped with a plurality of conveying rolls 6 spaced apart along the conveying direction, the back plate 4 is provided with a black section 4a which is positioned to overlap with the gap 6a between two adjacent conveying rolls 6, and the radiation thermometer 3 has a linear measurement scanning range S that extends in the width direction, and the measurement scanning range S is directed towards the gap 6a between two conveying rolls 6.

Description

Technical Field

[0001] The present invention relates to conveyance equipment for steel wire rod coils.

Background Art

[0002] A steel wire rod after hot rolling is, for example, formed into a spiral shape by a laying head, placed on a conveyor and conveyed. The steel wire rod on the conveyor is shaped into non-concentric, mutually overlapping rings. Hereinafter, the steel wire rod shaped into non-concentric, mutually overlapping rings is referred to as a steel wire rod coil. The steel wire rod coil is conveyed by the conveyor to a regulated cooling facility and cooled at a predetermined cooling rate.

[0003] Meanwhile, in the steel wire rod coil, since the multiple rings made of the steel wire rod overlap each other, the steel wire rod coil is provided with dense sections where the steel wire rods closely overlap each other and sparse sections where the steel wire rods have little overlap. When the steel wire rod coil is viewed in plan, the dense sections are located on both sides in the width direction orthogonal to the conveyance direction, and the sparse section is located at the center in the width direction. In the dense sections, the steel wire rods overlap each other, so the cooling rate tends to be slow, and in the sparse section, the steel wire rods do not overlap each other, so the cooling rate tends to be fast. As described above, the cooling rate tends to differ between the dense sections and the sparse section of the steel wire rod coil, and there is a problem that the entire steel wire rod coil cannot be cooled uniformly.

[0004] Further, in the regulated cooling line for steel wire rods, the temperature of the steel wire rod coil is measured from the side thereof by a radiation thermometer installed on the side of the conveyor. Therefore, the surface temperature of the dense sections facing the radiation thermometer can be measured relatively accurately, but the surface temperature of the sparse section located outside the measurement range of the radiation thermometer cannot necessarily be measured accurately.

[0005] Furthermore, taking advantage of the characteristics of radiation thermometers that can measure the temperature in a certain range, it has been considered to install radiation thermometers above the conveyor to measure the surface temperature of both the dense and coarse parts of steel wire coils being transported on the conveyor. However, the temperature of steel wire coils being transported on the conveyor is not always constant, and relatively hot and relatively cold steel wire coils are transported in no particular order. For example, if relatively hot steel wire coils are transported continuously, the temperature of the transport rolls that make up the conveyor and the back plate installed below the conveyor will gradually rise. Subsequently, when relatively cold steel wire coils are transported, the temperature of the transport rolls and back plate may exceed the surface temperature of the relatively cold coarse part of the steel wire coil. In this case, the surface temperature of the dense part of the relatively hot steel wire coil can be measured, but the surface temperature of the coarse part cannot be measured accurately. In order to understand the temperature variation of steel wire coils, it is necessary to accurately measure the surface temperature of the coarse part.

[0006] Patent documents 1 to 3 describe conventional methods for measuring the temperature of steel wire. However, none of the methods described in patent documents 1 to 3 accurately measured the temperature of the dense and coarse parts of the steel wire coil. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2002-039865 [Patent Document 2] Japanese Patent Application Publication No. 10-192948 [Patent Document 3] Special Publication No. 2019-505384 [Overview of the project] [Problems that the invention aims to solve]

[0008] The present invention has been made in view of the above circumstances, and aims to provide a steel wire coil conveying device that enables accurate measurement of the temperature of the dense and coarse parts of the steel wire coil. [Means for solving the problem]

[0009] To solve the above problems, the present invention adopts the following configuration. [1] A conveying device equipped with a function to measure the surface temperature of a steel wire coil while conveying the steel wire coil after hot rolling, A conveyor that transports the non-concentric, overlapping ring-shaped steel wire coils along the transport direction, A two-color radiation thermometer is installed above the conveyor to measure the surface temperature of the steel wire coil, The conveyor is further equipped with a back panel installed below it, The conveyor is equipped with a plurality of conveying rolls that are spaced apart along the conveying direction. At least a portion or all of the surface of the back plate facing the conveyor is provided with a black area having an emissivity of 0.95 to 1.00. The black portion of the back panel is positioned to overlap with the gap between two adjacent transport rolls. The aforementioned radiation thermometer has a linear measurement scanning range that extends in the width direction perpendicular to the transport direction, A conveying apparatus for steel wire coils, wherein the measuring scanning range of the radiation thermometer is directed towards the gap between the two conveying rolls. [2] The black portion is rectangular in shape, with its longer side aligned with the width direction and its shorter side aligned with the transport direction. The distance M between the shorter sides is greater than the width R in the width direction occupied by the steel wire coil placed on the conveyor. The steel wire coil conveying equipment according to [1], wherein the distance N between the long sides is greater than the diameter ψ of the steel wire constituting the steel wire coil. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a steel wire coil conveying system that enables accurate measurement of the temperatures of the dense and coarse parts of the steel wire coil. [Brief explanation of the drawing]

[0011] [Figure 1] A schematic diagram showing a steel wire rod coil conveyance facility that is an embodiment of the present invention. [Figure 2] A schematic perspective view showing the main part of the steel wire rod coil conveyance facility that is an embodiment of the present invention. [Figure 3] A schematic plan view showing the main part of the steel wire rod coil conveyance facility that is an embodiment of the present invention. [Figure 4] A schematic plan view showing a back plate provided in the steel wire rod coil conveyance facility that is an embodiment of the present invention. [Figure 5] A diagram showing the relationship between the radiation angle and the measurement error when the surface temperature of a steel wire rod is measured by a radiation thermometer. [Figure 6] A diagram for explaining a method for measuring the surface temperature of a steel wire rod coil by the steel wire rod coil conveyance facility that is an embodiment of the present invention. [Figure 7] A graph showing an example of the measurement result of the surface temperature of a steel wire rod coil obtained by the steel wire rod coil conveyance facility that is an embodiment of the present invention. [Figure 8] A graph showing an example of the measurement result of the surface temperature of a steel wire rod coil obtained by a steel wire rod coil conveyance facility of a comparative embodiment. [Mode for Carrying Out the Invention]

[0012] Hereinafter, the steel wire rod coil conveyance facility that is an embodiment of the present embodiment will be described. The conveyance facility 1 of the present embodiment has a function of measuring the surface temperature of the steel wire rod coil 5 while conveying the hot-rolled steel wire rod coil 5. This function is realized by the conveyor 2 and the radiation thermometer 3. More specifically, as shown in FIGS. 1 to 4, the conveyance facility 1 of the present embodiment includes a conveyor 2, a radiation thermometer 3 installed above the conveyor 2, and a back plate 4 installed below the conveyor 2.

[0013] The steel wire rod coil 5 being conveyed is placed on the conveyor 2. That is, the steel wire rod coil 5 is spirally wound by the winder 11 of the hot rolling facility, and then placed on the conveyor 2 to be in a state of being conveyed. The steel wire rod coil 5 is shaped into non-concentric and mutually overlapping ring forms. Here, each individual ring constituting the steel wire rod coil 5 may be referred to as a steel wire rod ring 5a. Further, the direction orthogonal to the conveyance direction L of the steel wire rod coil 5 is defined as the width direction W. The width of the steel wire rod coil 5 along the width direction W is R (mm).

[0014] The conveyor 2 is provided with a plurality of conveyance rolls 6. The conveyance rolls 6 are arranged at intervals along the conveyance direction of the steel wire rod coil 5. The length Lr of the conveyance roll 6 is larger than the width R (mm) of the steel wire rod coil 5 along the width direction W. Further, the interval Lg between the conveyance rolls 6 is larger than the diameter of the steel wire rod ring 5a constituting the steel wire rod coil 5. Thereby, the steel wire rod coil 5 being conveyed does not fall off from the conveyance rolls 6. Note that the interval Lg between the conveyance rolls 6 is the shortest distance between the roll surfaces of the adjacent conveyance rolls 6.

[0015] The radiation thermometer 3 is disposed above the conveyor 2. The radiation thermometer 3 is a two-color type radiation thermometer. Further, the radiation thermometer 3 has a linear measurement scanning range S extending in the width direction W. The radiation thermometer 3 is capable of measuring the surface temperature of the steel wire rod coil 5 passing through the measurement scanning range S. The measurement scanning range S of the radiation thermometer 3 is directed to the gap 6a between the conveyance rolls 6. Further, the radiation thermometer 3 is preferably positioned above the center position in the width direction W of the steel wire rod coil 5 conveyed on the conveyor 2. The installation height of the radiation thermometer 3 from the conveyor 2 is not particularly limited, and may be any height that allows accurate temperature measurement by the radiation thermometer 3.

[0016] The back plate 4 is positioned below the conveyor rolls 6. The back plate 4 is made of a metal plate such as a steel plate. The distance between the conveyor rolls 6 and the back plate 4 is, for example, about 50 to 300 mm. The back plate 4 is attached to a support part (not shown) that supports the conveyor rolls 6 in order to improve the overall strength of the conveyor 2. The back plate 4 also plays a role in receiving and collecting scale that falls off the steel wire coils 5 during conveyance.

[0017] The surface 4b of the back panel 4 on the conveyor 2 side in this embodiment is a surface that exhibits a metallic luster, but at least a part of the surface 4b is a black portion 4a that is colored black. The black portion 4a is formed, for example, by applying black paint to the surface 4b on the conveyor 2 side. The emissivity of the black portion 4a should be 0.95 to 1.00, and may be 1.00. The black portion 4a of the back panel 4 is positioned to overlap with the gap 6a between two adjacent conveying rolls 6. That is, the black portion 4a is located directly below the gap 6a between the two conveying rolls 6. The measurement scanning range S of the radiation thermometer 3 is directed towards the gap 6a. Therefore, the black portion 4a of the back panel 4 is located on the extension of the measurement scanning range S of the radiation thermometer 3.

[0018] In addition, in this invention, the entire surface 4b of the back panel 4 on the conveyor 2 side may be made of black material 4a.

[0019] Figure 4 shows the back plate 4 and one steel wire ring 5a that constitutes the steel wire coil 5. As shown in Figure 4, the black portion 4a has a rectangular shape when viewed from the radiation thermometer 3 side. The longer sides of the rectangle are parallel to the width direction W. The shorter sides are parallel to the conveying direction L. The distance M between the shorter sides is preferably greater than the width R in the width direction occupied by the steel wire coil 5 placed on the conveyor 2. The distance N between the longer sides is preferably greater than the diameter ψ of the steel wire constituting the steel wire coil 5. It is more desirable that the size of the black portion 4a occupies the same range as the overlapping measurement scanning range S of the radiation thermometer 3 when it overlaps with the surface 4b of the back plate 4, or a range larger than the overlapping measurement scanning range S.

[0020] Next, we will explain the radiation thermometer 3 in detail. Since the cross-sectional shape of the steel wire constituting the steel wire coil 5 is circular, the surface of the steel wire is curved. Therefore, when using a non-contact, single-color infrared radiation thermometer 3, it is necessary to eliminate the effect of the decrease in radiation intensity due to the radiation angle. If the effect of the decrease in radiation intensity is not taken into consideration, the accuracy of measuring the temperature of the steel wire coil 5 will be significantly reduced.

[0021] Figure 5 shows the relationship between the radiation angle and the error in the measured temperature. In Figure 5, the semicircular line represents the contour line of the surface of a 5.2 mm diameter steel wire when viewed in cross-section. The horizontal axis represents the diameter of the steel wire, and the vertical axis represents the difference between the output value of the measurement taken with the radiation thermometer 3 when the surface temperature of the steel wire heated to 800°C is measured, and the actual temperature (800°C). As shown in Figure 5, it can be seen that the difference between the measurement taken by the radiation thermometer 3 and the actual temperature (800°C) increases sharply as you approach the end of the steel wire in the diameter direction. In the example shown in Figure 5, the position where the difference begins to increase sharply corresponds to a radiation angle of 50°.

[0022] Thus, when the angle of the steel wire surface relative to the direction of infrared radiation incidence (hereinafter referred to as the radiation angle) exceeds 50°, the radiation intensity decreases significantly, reducing the accuracy of temperature measurement. Therefore, it is necessary to minimize the effect of the radiation angle.

[0023] Therefore, in this embodiment, a two-color radiation thermometer is used instead of a single-color radiation thermometer.

[0024] Here, we will briefly describe the measurement principle of a two-color radiation thermometer. When a high-temperature object such as a steel wire coil 5 is superimposed on the measurement scanning range S of a two-color radiation thermometer, infrared radiation emitted from the steel wire coil 5 and infrared radiation emitted from the background other than the steel wire coil 5 are incident. Here, K1 / K2 is defined as the ratio of the amount of infrared radiation emitted from the steel wire coil 5 with wavelength λ1 (K1) to the amount of infrared radiation emitted with wavelength λ2 (where λ1 > λ2). Similarly, k1 / k2 is defined as the ratio of the amount of infrared radiation emitted from the background with wavelength λ1 (k1) to the amount of infrared radiation emitted with wavelength λ2 (k2). A two-color radiation thermometer measures temperature based on the difference in the ratio of the amounts of infrared radiation at two wavelengths λ1 and λ2 (K1 / K2, k1 / k2).

[0025] In a single-color infrared thermometer, the measurement is affected by the radiation angle. This is because the ratio of radiation intensity differs between the central and end portions of the steel wire when viewed from above. On the other hand, a two-color infrared thermometer measures temperature based on the difference in the ratio of radiation amounts of two infrared wavelengths λ1 and λ2 (K1 / K2, k1 / k2), and is therefore not affected by the radiation angle. Consequently, by using a two-color infrared thermometer as the infrared thermometer 3, the measurement accuracy of the temperature can be prevented from being affected by the radiation angle of the steel wire surface, thus preventing a decrease in measurement accuracy due to the radiation angle.

[0026] Since a two-color radiation thermometer has the above measurement principle, in order to accurately measure the temperature of the steel wire coil 5 using a two-color radiation thermometer, it is necessary to provide a black area 4a on a part of the surface of the back plate 4, which serves as the background during measurement.

[0027] In the black section 4a, the emissivity is very close to 1 because the surface is black. On the other hand, the emissivity of the surface of the hot-rolled steel wire coil 5 is generally in the range of 0.85 to 0.92. Furthermore, the emissivity of the surface of the back plate 4 other than the black section 4a is close to that of the surface of the steel wire coil 5.

[0028] Here, as the steel wire coil 5 passes through the measurement scanning range S, the steel wire ring 5a of the steel wire coil 5 intermittently passes over the black portion 4a of the back plate 4 when viewed from the position of the radiation thermometer 3. When the radiation thermometer 3 measures the surface temperature of the steel wire ring 5a of the steel wire coil 5, both the steel wire ring 5a of the steel wire coil 5 and the back plate 4 are simultaneously within the measurement scanning range S. Here, if a black portion 4a is provided on the back plate 4, the difference between the emissivity of the steel wire coil 5 and the emissivity of the black portion 4a becomes large. As a result, the radiation thermometer 3 can clearly distinguish between the steel wire coil 5 and the black portion 4a, and can identify the steel wire coil 5.

[0029] Furthermore, if the black portion 4a is not provided on the back panel 4, the difference between the emissivity of the steel wire coil 5 and the emissivity of the back panel 4 becomes small, making it difficult to clearly distinguish between the steel wire coil 5 and the back panel 4.

[0030] As a result, even when the temperature of the back plate 4 rises due to thermal radiation from the steel coil 5, the steel wire coil 5 and the black part 4a can be clearly distinguished, making it possible to accurately measure the surface temperature of the steel wire coil 5. In particular, it becomes possible to accurately measure the surface temperature of the rough part of the steel wire coil 5.

[0031] Furthermore, if the conveying equipment 1 is equipped with a two-color radiation thermometer 3 but lacks a black section 4a, the emissivity of the back plate 4 and the steel wire coil 5 will be similar, making it impossible for the radiation thermometer 3 to distinguish between the steel wire coil 5 and the back plate 4 as the background (making it impossible to detect the temperature difference between the two). Similarly, if the black section 4a is provided but a thermometer other than a two-color radiation thermometer is installed, the thermometer will also be unable to distinguish between the steel wire coil 5 and the back plate 4 as the background (making it impossible to detect the temperature difference between the two). Therefore, in this embodiment, both a two-color radiation thermometer 3 and a black section 4a are necessary to accurately measure the temperature of the dense and coarse parts of the steel wire coil 5.

[0032] Next, we will explain how to measure the surface temperature of the steel wire coil 5 using the conveying equipment 1 shown in Figures 1 to 3.

[0033] As shown in Figures 1 to 3, after hot rolling, the steel wire is shaped into a spiral by a winding machine 11 and then placed on a conveyor 2. The steel wire placed on the conveyor 2 is shaped into non-concentric, overlapping rings, forming a steel wire coil 5. The steel wire rings 5a that make up the steel wire coil 5 are continuous with each other.

[0034] As the steel wire coil 5 is transported by the conveyor 2, it sequentially passes through the measurement scanning range S of the radiation thermometer 3. The radiation thermometer 3 continuously measures the surface temperature of the steel wire coil 5 as it passes through the measurement scanning range S. Multiple measurement positions are set within the measurement scanning range S, and the surface temperature of the steel wire coil 5 is continuously measured at each measurement position.

[0035] In this embodiment, the conveying equipment 1 is equipped with a back plate 4, and the black portion 4a of the back plate 4 is directly below the measurement scanning range S of the radiation thermometer 3. As a result, even if the temperature of the back plate 4 rises due to thermal radiation from the steel coil 5, the steel wire coil 5 and the black portion 4a can be clearly distinguished, and the surface temperature of the steel wire coil 5 can be accurately measured. In particular, the surface temperature of the rough part of the steel wire coil 5, which can be relatively cold, can be accurately measured.

[0036] Furthermore, since the radiation thermometer 3 is a two-color radiation thermometer, it can accurately measure the surface temperature of the rough part of the steel wire coil 5, especially the temperature of the rough part which is relatively cold, without being affected by the radiation angle.

[0037] Furthermore, the temperature of the steel wire coil 5 when passing through the steel wire ring 5a and the temperature when not passing through may be determined by artificial intelligence that has undergone machine learning.

[0038] Furthermore, by measuring the temperature from above the steel wire coil 5 using a two-color radiation thermometer, it becomes possible to understand the overall temperature distribution of the steel wire coil 5.

[0039] Figure 6 shows the surface temperature measurement results when multiple measurement positions are set within the measurement scanning range S. In Figure 6, the symbols s1 to s8 are measurement lines corresponding to the multiple measurement positions. Measurement line s1 is the line through which the coarse part of the steel wire coil 5 passes. Measurement lines s7 and s8 are the lines through which the dense part of the steel wire coil 5 passes. Multiple steel wire rings 5a constituting the steel wire coil 5 pass intermittently through the measurement lines s1 to s8 below.

[0040] Furthermore, the graph shown at the bottom of Figure 6 plots the highest and lowest surface temperatures of the multiple steel wire rings 5a that intermittently passed through each measurement line s1 to s8. The highest and lowest temperatures here represent the highest and lowest temperatures of the multiple steel wire rings 5a contained in one steel wire coil 5. As is clear from Figure 6, both the highest and lowest temperatures are higher in measurement line s7, which passes through the dense part of the steel wire coil 5, than in measurement line s1, which passes through the coarser part. In addition, the graph in Figure 6 allows us to understand the distribution of surface temperature in the steel wire coil 5.

[0041] Regarding the surface temperature distribution, it can be seen that the temperature distribution in the width direction W of the steel wire coil 5 can be determined from the temperature differences between each measurement line s1 to s8. Furthermore, it can be seen that the temperature distribution in the transport direction L of the steel wire coil 5 can also be determined from the difference between the highest and lowest temperatures of each measurement line s1 to s8.

[0042] Figure 7 shows an example of the results of measuring the temperature distribution of the steel wire coil 5 using the conveying equipment 1 of this embodiment. Figure 8 shows an example of the results of measuring the temperature distribution of the steel wire coil 5 using a comparative conveying equipment equipped with a back plate 4 without the black portion 4a.

[0043] In Figures 7 and 8, the horizontal axis represents the distance from the center of the steel wire coil 5 in the width direction W, and the vertical axis represents the surface temperature. Furthermore, in Figures 7 and 8, the max temperature is the highest temperature in the steel wire coil 5, and the min temperature is the lowest temperature in the steel wire coil 5. The maximum temperature in Figures 7 and 8 is generally the temperature of the dense parts, and the minimum temperature in Figures 7 and 8 is generally the temperature of the coarse parts.

[0044] Furthermore, in the comparative configuration, if the temperature of the back plate 4 is higher than the lowest temperature of the steel wire coil 5, the control is set to forcibly set the measurement temperature to 400°C.

[0045] In the embodiment shown in Figure 7, it can be seen that the lowest temperature (coarse temperature) of the steel wire coil 5 can be accurately measured. On the other hand, in the comparative configuration shown in Figure 8, most of the lowest temperature (coarse temperature) of the steel wire coil 5 falls at the 400°C threshold. Therefore, in the comparative configuration, it can be seen that the lowest temperature (coarse temperature) of the steel wire coil 5 cannot be accurately measured.

[0046] As described above, the conveying equipment 1 of this embodiment makes it possible to accurately measure the temperature of the dense and coarse parts of the steel wire coil 5. [Explanation of Symbols]

[0047] 1…Conveying equipment 2... Conveyor 3... Radiation thermometer 4…Back plate 4a...Black area 5...Steel wire coil 5a...Steel wire ring 6…Conveyor Roll 6a...Void

Claims

1. A conveying device equipped with a function to measure the surface temperature of a steel wire coil while conveying the steel wire coil after hot rolling, A conveyor that transports the non-concentric, overlapping ring-shaped steel wire coils along the transport direction, A two-color radiation thermometer is installed above the conveyor to measure the surface temperature of the steel wire coil, The conveyor is further equipped with a back panel installed below it, The conveyor is equipped with a plurality of conveying rolls that are spaced apart along the conveying direction. At least a portion or all of the surface of the back plate on the conveyor side is provided with a black area having an emissivity of 0.95 to 1.

00. The black portion of the back panel is positioned to overlap with the gap between two adjacent transport rolls. The aforementioned radiation thermometer has a linear measurement scanning range that extends in the width direction perpendicular to the transport direction, A conveying apparatus for steel wire coils, wherein the measuring scanning range of the radiation thermometer is directed towards the gap between the two conveying rolls.

2. The black portion is rectangular in shape, with its longer side aligned with the width direction and its shorter side aligned with the transport direction. The distance M between the shorter sides is greater than the width R in the width direction occupied by the steel wire coil placed on the conveyor. The steel wire coil conveying equipment according to claim 1, wherein the distance N between the long sides is greater than the diameter ψ of the steel wire constituting the steel wire coil.

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