JPH0526733A - Device for measuring temperature distribution in width direction of rolled material - Google Patents

Abstract

PURPOSE:To enable temperature distribution in width direction of a rolled material to be detected highly precisely and accurately by combining a temperature detector which measures temperature distribution in axial direction of the rolled material and a CCD camera which measures a plate width of the rolled material. CONSTITUTION:A rotary mirror 6 within a scanning unit 2 of a scanning-type radiation thermometer scans a surface of a strip 1 at a scanning angle of approximately 60 degrees, converts temperature distribution in axial direction of the strip 1 which is detected by a detection portion 8 of a silicon cell into an electrical signal, amplifies it, and then feeds it to an operation portion 10. On the other hand, a CCD camera control portion 12 detects a plate width value of the strip 1 with an accuracy of + or -0.125mm according to an image of both edge portions of the strip 1 which are input from CCD cameras 3 and 4 and then outputs it to a signal-processing device 11. The device 11 performs signal processing of a temperature distribution signal in width direction which is input from the operation portion 10 and the plate width value which is input from the control portion 12 according to a distance from a line center which is an installation reference and then accurately measures the temperature distribution in width direction of the strip 1 instantly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a widthwise temperature distribution measuring device for measuring a temperature distribution of a material to be rolled in a hot rolling process.

[0002]

2. Description of the Related Art In the production of hot-rolled products, rolling is performed sequentially while moving a heated material in the rolling direction. In such a rolling process, it is necessary to maintain the temperature of the material to be rolled within an appropriate range. However, in general, the edge of the material to be rolled is easier to cool than the center, so the surface temperature of the rolled material on the entry side of the finish rolling mill is about 50 to 100 ° C. lower at both edges than in the center. ing. In this way, both edge parts whose temperature is lower than that of the center part are rolled by the finish rolling machine as they are, and thus the temperature difference causes edge stretching and flatness failure in the rolled material, and Since the hardness of the edge portion of the rolling roll increases due to the temperature difference in the width direction of the rolled material, the roll wear at the abutting portion is more severe than that at the central portion, and the life of the roll is short and the roll replacement frequency increases. ..

In order to prevent the temperature of both edges of the rolled material from decreasing during the hot rolling process, as shown in FIG. 4, an edge heater 32 is installed on the inlet side of the finishing rolling mill 31, and the edge heater 32 and the finishing rolling mill 31 are installed. A scanning radiation thermometer 33 is installed in between, and the widthwise temperature distribution of the rolled material 34 is detected by the signal processing device 35 and output to the edge heater control unit 36. The edge heater control unit 36 compares the edge portion temperature raising target value input from the upper process computer 37 with the width direction temperature distribution of the rolled material 34 input from the signal processing device 35, and controls heating of both edge portions. To compensate for the temperature drop. However, in order to accurately heat only the both edge portions where the temperature is lowered by the edge heater 32 to raise the temperature, the width direction accurately corresponding to the position of the rolled material 34 in the width direction, particularly near both edge portions. It is necessary to measure the temperature distribution of.

Conventionally, as a method for measuring the widthwise temperature distribution of a rolled material in a hot rolling process, line scanning is repeated in the widthwise direction of the rolled material by an infrared radiation thermometer to correspond to the temperature of each part of the surface of the rolled material. A temperature signal is generated and waveform-shaped into a rectangular wave signal having a width substantially equal to the temperature signal, and the rectangular wave signal is time-integrated to be positioned at a predetermined distance from at least one end in the width direction on the scanning line of the rolled material. Or sampling the temperature signal when the set signal corresponding to a plurality of points and the integrated value become substantially equal to each other, regardless of the width of the rolled material and the fluctuation of the moving path, A method of automatically detecting the surface temperature of a rolled material substantially continuously in the moving direction (Japanese Patent Laid-Open No. 50-281381), and heating in a heating furnace in the process of manufacturing a forged tube. A temperature detector for detecting an image of the skelp in the width direction, and a temperature indicator for displaying an output signal of the temperature detector. Supplied from the self-propelled photodiode array projected and the output pulse of the clock pulse generation circuit, and the photodiode array drive circuit that supplies the electrical output of the photodiode to the amplifier in synchronization with the pulse cycle There has been proposed a device (Japanese Patent Publication No. 59-29805) equipped with a sample-and-hold circuit for maintaining a pulsed signal voltage at a predetermined level for a certain period.

[0005]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
The width-direction thermometer disclosed in Japanese Patent Publication No. 381 and Japanese Patent Publication No. 59-29805 is a rotating mirror type scanning scanning type, and an edge recognition method of a rolled material is a method of recognizing an edge position at a self-temperature threshold level. Is. On the other hand, the edge heater installed in front of the finishing rolling mill in the hot rolling process accurately measures the temperature distribution from the edge ends to the center direction with reference to both edge ends, and the entire temperature becomes uniform. Need to be heated. However, the method for recognizing the edge position by the self-temperature threshold level is affected by the radiant heat from the rolled material 34 and the reflected heat from the rolls as shown in FIG. The rising edge of the edge portion is unclear, and the plate width TW recognized by the thermometer from the temperature pattern detected by the width direction thermometer head portion 41 is the actual plate width because the edge position is recognized by the temperature threshold level 42. W
An error 43 is generated as compared with the above, and the edge portion cannot be accurately recognized. The surface temperature of the measured material is the plate width,
It is not uniform depending on the plate thickness and product type, but it varies between 1000 ° C and 1150 ° C on the entry side of the finishing rolling mill, and the temperature threshold level value for edge recognition also needs to change accordingly. To do. Further, it is impossible to eliminate external influences such as reflected heat from the roll and radiant heat of the rolled material at the edge portion, and the edge detection accuracy is limited to about ± 5 mm. Therefore, it is difficult to accurately heat the entire rolled material by the edge heater so that the whole rolled material has a uniform temperature.

The object of the present invention is to continuously and accurately correspond to the temperature distribution in the width direction of the rolled material in the hot rolling process and highly accurately match the vicinity of both edge portions of the rolled material with the position in the width direction of the rolled material. An object of the present invention is to provide a temperature distribution measuring device that can measure the temperature.

[0007]

[Means for Solving the Problems] The present inventors conducted various test studies in order to achieve the above object. As a result, in addition to the scanning radiation thermometer that measures the temperature distribution in the width direction of the rolled material, a CCD camera of the lower light source system that measures the plate width value of the rolled material is installed, and the strip plate width value measured by the CCD camera. And the temperature distribution in the width direction of the rolled material measured by the scanning radiation thermometer to a temperature distribution corresponding to the distance in the width direction of the rolled material by the signal processing device. It was clarified that the measurement can be performed accurately corresponding to the position in the width direction of the, and the present invention was reached.

That is, according to the present invention, a temperature detector for measuring a temperature distribution in the width direction of a rolled material, a CCD camera of a lower light source type for measuring a strip width value of the rolled material, and a rolled material input from the temperature detector The signal processing device comprises a width direction temperature distribution signal and a plate width value signal of the rolled material input from the CCD camera, which corresponds to the distance in the rolled material width direction.

[0009]

According to the present invention, since the lower light source type CCD camera for measuring the strip width value of the rolled material is installed in addition to the temperature detector for measuring the temperature distribution in the width direction of the rolled material, rolling by the temperature detector is performed. The temperature distribution in the width direction of the rolled material can be accurately measured instantaneously by performing corresponding signal processing on the distance distribution from the line center which is the installation reference. The bottom light source of the bottom light source type CCD camera that measures the width and length of the rolled material is different from the wavelength of infrared rays from the rolled material by using a fluorescent lamp, so the CCD camera accurately measures the edge portion of the rolled material. Can be determined.

As the temperature detector in the present invention, a radiation thermometer using a silicon cell having a rotating mirror, or a solid-state image pickup device such as a CCD linear array is used.
It is either a scanning type temperature detector that installs these scanning units above the line center, or a fixed type temperature detector that projects a rolled material image onto a self-propelled photodiode array or the like via an imaging optical system. However, the same effect can be obtained. Further, as shown in FIG. 1, the bottom light source type CCD camera type plate width meter has a CCD camera 21 on both sides at a predetermined distance from the line center LC, that is, at a distance ½ of the average plate width in the hot rolling mill. , 22 are installed. The plate width W of the rolled material 23 is detected by the CCD cameras 21 and 22, and the plate width W = R + L, R = CCW / 2 + RM,
L = CCW / 2 + LM. As a result, even if the rolled material 23 meanders, the absolute width can be measured within the visual field range 24 of the CCD cameras 21 and 22. 2
Reference numeral 5 is a fluorescent lamp as a lower light source. Therefore, by correlating the measured strip width value and the width direction temperature distribution measured by the temperature detector with the distance from the line center LC which is the corresponding installation reference, the rolled material width direction temperature distribution can be accurately measured. ..

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to FIGS. FIG. 2 is an explanatory view of the measurement principle of the width direction temperature distribution measuring device of the present invention. Figure 3
FIG. 3 is a control system diagram of the width direction temperature distribution measuring device of the present invention.

In FIG. 3, 1 is a strip before finish rolling of a hot rolling mill, 2 is a scanning radiation thermometer scanning unit for measuring the widthwise temperature distribution of the strip 1 installed above the line center, 3, 4 is a CCD camera installed at a distance of 1/2 of the average plate width of the hot rolling mill from the line center LC, and 5 is a fluorescent lamp of a lower light source provided below the strip 1. In the scanning unit 2 of the scanning radiation thermometer, a hexagonal rotary mirror 6, a rotary encoder 7, a silicon cell detector 8 and an amplifier 9 are incorporated, and the scanning angle is 60 ° in the direction perpendicular to the traveling direction of the strip 1. , Scanning speed 50 m / sec, scanning frequency 10 times / sec, temperature measuring range 600 to 1200 ° C., instantaneous field of view 3.5 mm × 30 mm, the surface of the strip 1 was scanned, and the strip 1 detected by the detection unit 8 of the silicon cell was measured.
The temperature distribution in the width direction is converted into an electric signal, amplified by the amplifier 9, and then input to the operation unit 10.

The electric signal of the temperature distribution in the width direction of the strip 1 from the amplifier 9 input to the operation unit 10 is converted into the temperature distribution in the width direction and output to the signal processing device 11. On the other hand, the CCD cameras 3 and 4 have a resolution of 4000 bits, a visual field range of 500 mm, and a width direction length of 0.12 per bit.
Both edges of the strip 1 are imaged at 5 mm and output to the CCD camera control unit 12. The CCD camera control unit 12
The strip width value of the strip 1 is accurately ± 0.1 from the images of both edges of the strip 1 input from the CCD cameras 3 and 4.
It is detected at 25 mm and output to the signal processing device 11. The signal processor 11 uses the width direction temperature distribution signal 13 shown in FIG. 2 input from the operation unit 10 and the plate width value W shown in FIG. Corresponding signal processing is performed at a distance from LC, and as shown in FIG. 2, the temperature distribution 14 in the width direction of the strip 1 can be instantaneously and accurately measured.

Therefore, if the temperature distribution 14 in the width direction of the strip 1 processed by the signal processing device 11 is output to the edge heater control section to control the heating by the edge heater, the edge section reaches a predetermined temperature increase target value. It can be controlled with high precision and accuracy. According to the present invention, the overall edge position detection accuracy of ± 1 mm can be ensured, and ± 1 mm of the conventional self-temperature threshold level method is used.
It is possible to significantly improve the position recognition accuracy as compared with 5 mm.

[0015]

As described above, according to the present invention,
By combining the temperature detector of the rolled material and the edge position detection mechanism by CCD camera, the edge position detection accuracy of the conventional self-temperature threshold level system is ± 5m.
The edge position can be detected more than 5 times more accurately than m, and the widthwise temperature distribution of the rolled material can be detected with high accuracy, and the temperature of the rolled material edge part can be accurately adjusted by the edge heater. Can be done.

[Brief description of drawings]

FIG. 1 is an explanatory view of a measurement principle of a bottom light source type CCD camera type plate width meter of the present invention.

FIG. 2 is an explanatory diagram of a measurement principle of the width direction temperature distribution measuring device of the present invention.

FIG. 3 is a control system diagram of the width-direction temperature distribution measuring device of the present invention.

FIG. 4 is a control system diagram of an edge heating device in a conventional hot rolling mill.

FIG. 5 is an explanatory diagram of a measurement principle of edge position detection of a conventional self-temperature threshold level method.

[Explanation of symbols]

 1, 23, 34 Strip 2, 41 Scanning Unit 3, 4, 21, 22 CCD Camera 5, 25 Fluorescent Lamp 6 Rotating Mirror 7 Rotary Encoder 8 Detecting Section 9 Amplifier 10 Operating Section 11, 35 Signal Processing Device 12 CCD Camera Control Section 13 Width direction temperature distribution signal 14 Width direction temperature distribution 24 Field-of-view range 31 Finishing mill 32 Edge heater 33 Scanning radiation thermometer 36 Edge heater control unit 37 Upper process computer 42 Temperature threshold level 43 Error

Claims (1)

Claim: What is claimed is: 1. A temperature detector for measuring a temperature distribution in the width direction of a rolled material, and a lower light source type C for measuring a strip width value of the rolled material.
From a CD camera and a signal processing device for processing the widthwise temperature distribution signal of the rolled material input from the temperature detector and the plate width value signal of the rolled material input from the CCD camera in correspondence with the distance in the widthwise direction of the rolled material. Width direction temperature distribution measuring device for hot rolled material.