JP2005003542A - Method and apparatus for detecting marking position of steel piece - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for detecting a marking position of a steel piece, which marks a flaw part with a marking material containing a florescent substance and which can precisely detect the marking position. <P>SOLUTION: In the method for detecting the marking position of the steel piece, the marking position is detected by magnetizing the steel piece, attaching a magnetic powder liquid containing the fluorescent substance to a magnetic pole generated at the flaw part so as to detect the flaw, marking the flaw part with the marking material containing the fluorescent substance, then performing the irradiation with ultraviolet rays from an ultraviolet irradiation light source so that the marking emits a florescent light, converting the optical signal of the fluorescent emission light into an electric signal by an optical sensor, and processing electric signal. The marking position is detected, using the marking material which emits the fluorescent light having the wavelength different from those of the ultraviolet rays of the ultraviolet irradiation light source and the florescent emission light of the magnetic powder liquid, and using the optical sensor having the characteristic in which the sensitivity for the wavelength of the ultraviolet rays of the ultraviolet irradiation light source and for the wavelength of the fluorescent emission light of the magnetic powder liquid is lower than the sensitivity for the wavelength of the florescent emission light of the marking material. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method and an apparatus for detecting a marking position of a steel slab, and more particularly to a technique for marking a ridge on a steel slab subjected to fluorescent magnetic particle testing and detecting the marking position.
[0002]
[Prior art]
For example, as disclosed in Japanese Patent Application Laid-Open No. 7-14117 (Patent Document 1), Japanese Patent Application Laid-Open No. 2001-154016 (Patent Document 2), etc., as a method for detecting a surface defect of a steel slab, fluorescent magnetic particle flaw detection is widely used. It's being used. The magnetic particle flaw detection is a method for detecting wrinkles by magnetizing a ferromagnetic material such as a steel material and utilizing magnetic powder liquid adhering to the magnetic pole generated in the wrinkle portion. Fluorescent magnetic particle flaw detection, which is a type of magnetic particle flaw detection, facilitates detection of wrinkles by including a fluorescent substance in a magnetic powder liquid and irradiating it with ultraviolet rays. In general, detection is performed visually.
[0003]
Marking is performed on the position of the wrinkle detected by the above-mentioned fluorescent magnetic particle flaw detection, and the wrinkle part is removed in the next process. If this marking position can be recognized automatically, the wrinkle part can be automatically removed by cutting. A method for recognizing a marking position that can realize this has been proposed in Japanese Patent Laid-Open No. 8-271234 (Patent Document 3) and Japanese Patent Laid-Open No. 11-264723 (Patent Document 4).
[0004]
Patent Document 3 proposes a method of marking a surface defect portion of a slab with chalk and detecting the position with an optical sensor such as a CCD camera.
[0005]
Patent Document 4 discloses a method for improving the reading accuracy of the marking position by including a fluorescent substance in the marking material for displaying the position of the heel of the steel slab, and irradiating the marking material with fluorescence by irradiating ultraviolet rays in the shielding hood. Proposed.
[0006]
[Patent Document 1]
JP 7-14117 A [Patent Document 2]
JP 2001-154016 A [Patent Document 3]
JP-A-8-271234 [Patent Document 4]
Japanese Patent Laid-Open No. 11-264723
[Problems to be solved by the invention]
However, in the method proposed in Patent Document 3, it is difficult to distinguish from marking if there is unevenness or dirt on the surface of a steel piece such as a slab, and it is difficult to detect a marking position with high accuracy. In particular, after performing the magnetic particle flaw detection, the magnetic powder liquid remains on the surface, and the identification becomes more difficult.
[0008]
Further, in the method proposed in Patent Document 4, since the marking material contains a fluorescent substance and is irradiated with ultraviolet rays to emit light, the marking can be detected more easily than the method proposed in Patent Document 3, but the fluorescent magnetic particle flaw detection is performed. After performing the above, a large amount of magnetic powder containing a fluorescent material (hereinafter also referred to as fluorescent magnetic powder) remains on the surface. For this reason, light emission from the remaining fluorescent magnetic powder becomes noise, and it is very difficult to detect only the marking. Then, although washing with water etc. can be considered as a method for removing the remaining fluorescent magnetic powder, it is not easy to wash away only the remaining fluorescent magnetic powder without affecting the marking material in the first place. This is because it penetrates deep into the steel surface with fine irregularities. (2) Further, in order to read the marking by washing it out, it is necessary to go through the steps of attaching a magnetic magnetic powder solution → implementing the marking → washing off → reading the marking. For this reason, it is difficult to wash away only the fluorescent magnetic powder, and there is a high possibility that the marking is also washed away. On the other hand, there is also a problem that light reflected by the surface of the steel material becomes noise.
[0009]
The present invention has been made in view of the above-mentioned problems, and its purpose is not to wash away the fluorescent magnetic powder liquid after the fluorescent magnetic powder flaw detection, but to mark the heel portion with a marking material containing a fluorescent substance thereafter. The present invention provides a method and an apparatus for detecting the marking position of a steel piece that can accurately detect the marking position.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, a method for detecting a marking position of a steel slab according to the present invention (Claim 1) magnetizes the steel slab and attaches a magnetic powder liquid containing a fluorescent substance to the magnetic pole generated in the flange portion. Detecting wrinkles, marking with a marking material containing fluorescent material on the wrinkles, and then irradiating ultraviolet rays from an ultraviolet irradiation light source to cause the markings to fluoresce. Is a method of detecting the marking position of a steel piece by processing the electrical signal and detecting the marking position of the slab, and the fluorescent light having a wavelength different from the wavelength of the ultraviolet light of the ultraviolet irradiation light source and the fluorescence emission wavelength of the magnetic powder is used. Uses a marking material that emits light, and is less sensitive to the ultraviolet light wavelength of the ultraviolet light source and to the fluorescent light emission wavelength of the magnetic powder liquid than the sensitivity of the marking material to the fluorescent light emission wavelength. And it detects a marking position using an optical sensor having characteristics.
[0011]
In the steel piece marking position detecting method according to claim 1, the optical sensor has a high transmittance with respect to the wavelength band of the fluorescence emission from the marking material, and the ultraviolet wavelength band of the ultraviolet irradiation light source and the magnetic powder liquid. It is preferable to provide an optical filter having a low transmittance with respect to the wavelength band of the fluorescence emission from (Claim 2). Further, in this case, the ultraviolet wavelength band of the ultraviolet irradiation light source is 300 nm to 413 nm, the fluorescent emission wavelength of the magnetic powder is 500 nm to 700 nm, the fluorescent emission wavelength of the marking material is 413 nm to 500 nm, and the transmission wavelength range of the optical filter is 413 nm to 413 nm. The thickness is preferably 500 nm. Further, the ultraviolet wavelength band of the ultraviolet irradiation light source may be 694 nm to 780 nm instead of 300 nm to 413 nm.
[0012]
Further, the steel piece marking position detecting device according to the present invention (Claim 5) magnetizes the steel piece, attaches a magnetic powder liquid containing a fluorescent substance to the magnetic pole generated in the saddle portion, and detects the soot. Marking with marking material containing fluorescent material in the part, and then irradiating ultraviolet rays from the ultraviolet light source to cause the markings to fluoresce. The optical signal emitted from the fluorescent light is converted into an electrical signal by an optical sensor, and the electrical A marking position detection device for a piece of steel that detects a marking position by processing a signal, wherein the fluorescent material of the marking material is different from the fluorescent light emission wavelength of the ultraviolet light of the ultraviolet light source and the fluorescent material of the magnetic powder liquid. Compared to the detection sensitivity of the fluorescence emission wavelength from the marking material, the optical sensor has a lower detection sensitivity for the ultraviolet wavelength of the ultraviolet irradiation light source and the fluorescence emission wavelength from the magnetic powder liquid. And it has a characteristic.
[0013]
In the present invention, as shown in FIG. 1, a step (a) of detecting flaws by performing flaw detection on a steel piece using a magnetic powder liquid (fluorescent magnetic powder liquid) containing a fluorescent material to detect wrinkles, The step of marking the portion with a marking material containing a fluorescent material having a fluorescent emission wavelength different from the wavelength of the ultraviolet light emitted from the ultraviolet light source and the wavelength of the fluorescent light emitted from the fluorescent magnetic powder solution (b), thereafter The steel piece is moved to a place where the whole is covered with a shielding hood, and the marking material is emitted by irradiating ultraviolet rays from the ultraviolet irradiation light source. The wavelength range of the irradiated ultraviolet rays and the fluorescence wavelength of the fluorescent magnetic powder liquid used in the fluorescent magnetic particle inspection A step (c) of recognizing the marking and recognizing the scissors by imaging the steel piece with an optical sensor such as a CCD camera to which an optical filter for removing the region is attached and performing image processing. of A light emitting wavelength range of the fluorescent magnetic particle solution used in the wavelength range and the fluorescent magnetic particle flaw of ultraviolet ray irradiated is removed, only the marking of the flaw portion is clearly photographed, it is possible to reduce wrong recognition of the marking. As a result, the accuracy of soot removal in the next step (d) is improved.
[0014]
In this case, the wavelength range of an ultraviolet irradiation light source having a metal halide lamp that is generally used is 300 nm to 413 nm and 694 nm or more (see, for example, paragraph [0008] of FIG. 8 and FIG. 8). Moreover, the emission wavelength of the commonly used fluorescent magnetic powder is 500 nm to 700 nm. Therefore, by setting the emission wavelength of the fluorescent substance included in the marking material to between 413 nm and 500 nm and the transmission wavelength of the optical filter also between 413 nm and 500 nm, the reflection of ultraviolet rays from the ultraviolet irradiation light source and the fluorescence emission from the fluorescent magnetic powder liquid are reduced. The influence can be reduced, and only the marking of the heel portion can be clearly photographed, and the erroneous recognition of the marking can be reduced. As a result, the accuracy of soot removal in the next step (d) is improved.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 2 is a schematic explanatory view of an apparatus applied to a steel piece marking position detection method according to the present invention, in which a is a plan view and b is an XX cross-sectional view of a.
[0016]
As shown in FIG. 2, the marking position detection device 1 includes a table roller 3 that conveys the steel piece 2, and a light shielding hood 4 that is installed so as to cover the side and upper side of the table roller 3. A CCD camera (light sensor) 6 having an optical filter 5 and an ultraviolet irradiation light source 7 are installed in the upper part of the light shielding hood 4.
[0017]
The slab 2 is preliminarily subjected to fluorescent magnetic particle flaw detection in the above process, and a fluorescent light having a fluorescent emission wavelength different from the fluorescent emission wavelength of the fluorescent substance of the fluorescent magnetic powder solution and the ultraviolet light wavelength of the ultraviolet irradiation light source 7 is provided in the flange portion. The marking 8 is made using a marking material containing a substance. Then, in the process of being transported on the table roller 3 and passing through the light shielding hood 4, ultraviolet light is irradiated from the ultraviolet irradiation light source 7 and imaged by the CCD camera 6 through the optical filter 5, and this imaging is subjected to image processing. Thus, the marking 8 is identified.
[0018]
【Example】
Using a fluorescent magnetic powder having an emission wavelength of 500 nm to 700 nm, a fluorescent magnetic powder flaw detection is performed on a target steel piece. Marking 8 is performed on the flange portion of the steel piece detected by the flaw detection with a fluorescent choke containing a fluorescent material having a central wavelength of light emission of 450 nm.
[0019]
In the shielding hood 6 of the marking position detection apparatus 1, a CCD camera 6 including an ultraviolet irradiation light source 7 having a metal halide lamp with wavelengths of 300 nm to 413 nm and 694 nm or more and an optical filter 5 with a transmission region of 430 nm to 470 nm is installed. Yes.
[0020]
When the steel piece 2 on which the marking 8 has been performed is conveyed on the table roller 3 and passed through the light shielding hood 4 and irradiated with the ultraviolet light source 7, the fluorescent magnetic powder used in the fluorescent magnetic particle inspection has a wavelength of 500 nm to 700 nm. The fluorescent chalk of the marking 8 that has emitted light in the region and marked the ridge part emits light with a wavelength of 450 nm as the center. Moreover, from the mirror surface part of the steel slab 2, light from the ultraviolet irradiation light source 7 is reflected in a wavelength range of 300 nm to 413 nm and 694 nm or more.
[0021]
Although the above-mentioned light is imaged by the CCD camera 6, the wavelength of the light observed by the optical filter 5 mounted on the CCD camera 6 is limited to 430 nm to 470 nm, and thus light emission from a fluorescent magnetic powder of 500 nm to 700 nm and 300 nm Only light emitted from the fluorescent chalk of the marking 8 centered at 450 nm is observed without being affected by light from the ultraviolet irradiation light source 7 of ˜413 nm and 694 nm or more (see FIG. 3).
[0022]
In the above embodiment, a fluorescent magnetic powder having an emission wavelength of 500 nm to 700 nm is used, a fluorescent magnetic powder flaw detection is performed on the target steel piece, and a mark portion of the steel piece detected by the flaw detection is marked with a fluorescent chalk. However, the present invention is not limited to this example. For example, when the fluorescent magnetic powder flaw detection is performed, a metal halide lamp is used in the light shielding hood, and the emission wavelength of the fluorescent magnetic powder liquid is the same. Fluorescent magnetic particle flaw detection is performed by photographing with a CCD camera equipped with an optical filter in the transmission region, and then marking 8 is performed with a fluorescent choke on the heel portion of the steel piece detected by the flaw detection. The marking position on the steel piece may be detected.
[0023]
As described above, in the case of fluorescent magnetic particle flaw detection, when imaged using a CCD camera, both imaged image data are added separately or simply, and then subjected to image processing (for example, binarization of white and black). Then, the wrinkle and the chalk are processed so that they are conspicuous, and the image processing of both is simply added to detect the wrinkle and the marking position. Based on this detection position, scoring is performed in a scoring process in a subsequent process. In this case, it is possible to simultaneously remove the wrinkles due to the detection with the fluorescent magnetic powder and the detection with the marking. Here, the image data may be subjected to image processing immediately after photographing (before marking) by the CCD camera in the fluorescent magnetic particle flaw detection, and the picking may be performed. In this case, the eyelid position is detected by the marking of the present invention after the normal process of fluorescent magnetic particle flaw detection. Alternatively, the image data may be image-processed immediately after photographing (before marking) with a CCD camera in fluorescent magnetic particle flaw detection, and marking may be performed with an automatic marking device.
[0024]
Moreover, in the said Example, although the case where the wavelength range of the ultraviolet irradiation light source 7 is 300 nm-413 nm and 694 nm or more (for example, 694 nm-780 nm) was taken as an example, this assumes the case where it test | inspects visually. Therefore, the present invention is not limited to this example, and an ultraviolet irradiation light source 7 having a wavelength range of 300 nm to 694 nm or more can be used. For example, the wavelength of 385 ± 5 nm shown in Patent Document 1 is used. It is also possible to use an ultraviolet irradiation light source 7 of the area. In this case, the wavelength range of the fluorescent chalk that can be used for marking can be expanded to 390 nm to 500 nm. However, if the wavelength of the ultraviolet irradiation light source 7 is narrowed, the absolute amount of light decreases, so that the emission intensity of the fluorescent chalk also decreases. It is necessary to select the ultraviolet irradiation light source 7 in consideration of the balance between the two. In addition, if the emission wavelength of the fluorescent magnetic powder liquid is increased, the wavelength of the fluorescent choke that can be used for marking can be increased. However, if the wavelength is increased, the visual sensitivity of the fluorescent magnetic powder flaw detection is lowered and the flaw detection capability is lowered. there is a possibility. In this case, it is necessary to select the wavelength in consideration of the balance between the two.
[0025]
In carrying out the present invention, the steel piece may be subjected to ultrasonic flaw inspection before and after magnetic particle flaw detection and before and after marking, and the data obtained therefrom may be used at the time of scraping. In addition, the scraping may be automated with a machine or manually. Further, scoring may be performed by combining the flaw position data of each flaw detection or may be performed separately. In addition, marking is generally performed manually by hand, but can also be performed mechanically. In addition, magnetic particle inspection and marking are basically performed separately on the front and back sides. However, in the case of marking, depending on the object to be inspected, it can also be performed at the same time. In addition, the scraping may be provided with a plurality of scraping devices in parallel or in series. Further, after the scraping, another magnetic particle flaw detection / marking / scoring may be performed again.
[0026]
【The invention's effect】
As described above, according to the present invention, the scissors portion is marked with a marking material containing a fluorescent substance without washing away the fluorescent magnetic powder after the fluorescent magnetic powder flaw detection, and the marked image is clearly captured. Therefore, accurate position information can be given to the removal of wrinkles in the next process.
[Brief description of the drawings]
FIG. 1 is a process explanatory diagram of a steel piece marking position detection method according to the present invention.
FIG. 2 is a schematic explanatory view of an apparatus applied to a steel piece marking position detection method according to the present invention, in which a is a plan view and b is an XX cross-sectional view of a.
FIG. 3 is an explanatory diagram of a wavelength range according to the present invention.
[Explanation of symbols]
1: Marking position detection device 2: Steel slab 3: Table roller 4: Light shielding hood 5: Optical filter 6: CCD camera 7: Ultraviolet irradiation light source 8: Marking

Claims (5)

The steel piece is magnetized, magnetic powder containing fluorescent material is attached to the magnetic pole generated in the saddle part, and the defect is detected, and marking is performed with a marking material containing the fluorescent substance on the saddle part, and then the ultraviolet light source is used. This is a method for detecting the marking position of a steel piece, in which the marking emits fluorescence by irradiating ultraviolet rays, the optical signal emitted from the fluorescence is converted into an electrical signal by an optical sensor, and the marking position is detected by processing the electrical signal. In addition, a marking material that emits fluorescence having a wavelength different from the wavelength of the ultraviolet light of the ultraviolet irradiation light source and the fluorescence emission wavelength of the magnetic powder is used, and the wavelength of the ultraviolet light of the ultraviolet light irradiation light source is higher than the sensitivity of the marking material to the fluorescent light emission wavelength. Steel mark markin using a photosensor having a low sensitivity to the fluorescence emission wavelength of the magnetic powder and the magnetic powder. Position detection method. In the method for detecting the marking position of a steel piece according to claim 1, as a photosensor having a characteristic that the sensitivity to the ultraviolet light wavelength of the ultraviolet irradiation light source and the fluorescence light emission wavelength of the magnetic powder liquid is lower than the sensitivity to the fluorescent light emission wavelength of the marking material, An optical sensor having an optical filter that has a high transmittance with respect to the wavelength band of the fluorescent light emitted from the marking material and a low transmittance with respect to the wavelength band of the ultraviolet light emitted from the ultraviolet light source and the wavelength band of the fluorescent light emitted from the magnetic powder liquid is used. A method for detecting the marking position of a steel piece. 3. The method for detecting the marking position of a steel piece according to claim 2, wherein the ultraviolet wavelength band of the ultraviolet irradiation light source is 300 nm to 413 nm, the fluorescent emission wavelength of the magnetic powder is 500 nm to 700 nm, and the fluorescent emission wavelength of the marking material is 413 nm to 500 nm. A method for detecting the marking position of a steel piece in which the transmission wavelength range of the optical filter is 413 nm to 500 nm. 3. The method for detecting the marking position of a steel piece according to claim 2, wherein the ultraviolet wavelength band of the ultraviolet irradiation light source is 694 nm to 780 nm, the fluorescent emission wavelength of the magnetic powder is 500 nm to 700 nm, and the fluorescent emission wavelength of the marking material is 413 nm to 500 nm. A method for detecting the marking position of a steel piece in which the transmission wavelength range of the optical filter is 413 nm to 500 nm. A steel piece is magnetized, a magnetic powder containing a fluorescent material is attached to the magnetic pole generated in the saddle part, and the soot is detected. Then, marking is performed with a marking material containing the fluorescent substance on the saddle part, and then an ultraviolet irradiation light source is used. A marking position detection device for a steel piece that detects the marking position by irradiating ultraviolet rays to cause the marking to emit fluorescent light, converting the fluorescent light signal into an electrical signal by an optical sensor, and processing the electrical signal. In addition, the fluorescent material of the marking material has a fluorescence emission wavelength different from the wavelength of the ultraviolet light of the ultraviolet irradiation light source and the fluorescence emission wavelength of the fluorescent material of the magnetic powder liquid, and the optical sensor is compared with the detection sensitivity of the fluorescence emission wavelength from the marking material. An apparatus for detecting the marking position of a steel piece, characterized by having a low detection sensitivity of the wavelength of the ultraviolet light of the ultraviolet light source and the fluorescence emission wavelength from the magnetic powder.

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