JP2000028547A - Steel plate surface inspection system - Google Patents

Abstract

(57) [Summary] [PROBLEMS] In a steel sheet surface defect inspection apparatus, surface defects of a cold rolled steel sheet manufactured by a plurality of processes are detected by a surface defect meter and a digital camera, and centrally managed. Reduce quality variations between processes. SOLUTION: Detection means for detecting a surface state of a steel sheet;
Comparing means for comparing a signal obtained by the detecting means with a predetermined reference value; calculating means for calculating a surface defect name and a defect grade based on the surface defect signal obtained by the comparing means; There are provided storage means for processing and recording the same, and display means for editing a surface defect image and defect information detected in each step and displaying this in each step.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for continuously manufacturing cold-rolled steel sheets, in which a surface defect of a cold-rolled steel sheet manufactured by a plurality of processes can be detected by a surface defect meter and a digital camera, and can be centrally managed. The present invention relates to an apparatus for inspecting the surface defect of a steel sheet.

[0002]

2. Description of the Related Art In a cold-rolled steel sheet, a surface inspection for quality assurance is performed on the entire surface and the entire length of the steel sheet. A cold-rolled steel sheet is manufactured through multiple processes before it is shipped as a product.
It may affect the processing in the next step. Therefore, it is necessary to know in which of the plurality of steps the defect has occurred. For this purpose, an inspection is performed for each step.

[0003] A large number of defective products will be generated if defects generated in the previous process or the present process are not processed immediately. Conventionally, surface inspection equipment and inspectors are assigned to each process. Each inspector individually performs an inspection to determine the presence or absence of a defect.

[0004] On the other hand, since there is no standard for the defect name and the defect grade for the surface defect of the steel sheet, at present, a sample is collected for each process and used as a defect limit sample. At that time, it is impossible to create exactly the same defect limit sample, so the quality evaluation is inconsistent due to individual inspections by each inspector and differences in samples between processes, etc., and in some cases, Inadequate communication of information resulted in duplication of work and incorrect confirmation.

Conventionally, surface defect meters for detecting various types of surface defects have been developed. Inspections which require detection of defect names and defect grades, even if the form of the defect is known, the surface defect It is difficult to determine an accurate defect name and defect grade by a meter and to detect all the defects necessary for quality control by a surface defect meter.

[0006] Therefore, inspection of this kind of surface defects is
It is necessary to use both the visual inspection by the inspector and the inspection by the surface defect meter, and to perform quality control by sharing the roles of each. Further, when a defect that is difficult for the inspector to determine occurs, it is necessary to collect a sample of the defective portion and perform a re-inspection operation, and the quality manager must determine this.

[0007] In addition, since the collected defect limit sample becomes unusable due to aging, the sample must be collected periodically. Hundreds of hundreds of samples are required for the defect limit samples required for inspection, and the sampling operation requires much labor and time.

[0008]

SUMMARY OF THE INVENTION
Japanese Patent Application Laid-Open No. 4-305147 proposes a method for centrally managing steel sheets.
No. 1 proposes a visual inspection method by an inspector.

However, in the method described in Japanese Patent Application Laid-Open No. 4-305147, it is difficult to determine a defect name and a defect grade. The defect name is determined by the cause of the defect, and the defect grade is determined by the defect area and defect depth. There is a problem when a difficult defect occurs. Defects that cannot be detected by the surface defect meter cannot be detected,
The problem of shipping as it is arises.

The method described in JP-A-5-327991 relates to a method for visually inspecting defect names and defect grades, and cannot solve the above-mentioned problems.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a main object of the present invention is to unify the quality control in a series of manufacturing processes of a cold-rolled steel sheet so that a plurality of cold-rolled steel sheets are manufactured. It is an object of the present invention to provide a method capable of reducing quality variation between processes, performing excellent quality control, and reducing the workload of an inspector.

[0012]

Means for Solving the Problems The invention described in claim 1 of the present application is a detecting means for detecting a surface state in each step of a steel sheet manufactured through a plurality of steps from rolling to recoil or shearing; A comparison unit that compares the detection signal of the detection unit with a predetermined reference value, and a calculation unit that calculates a surface defect name and a surface defect grade of the steel sheet based on the surface defect signal obtained by the comparison unit,
Image processing of the surface defect signal obtained by the comparing means, storage means for recording the processed image, and surface defect images detected in each of the plurality of steps, and edits the defect information, And a display means for simultaneously displaying in each of a plurality of steps.

According to a second aspect of the present invention, in the apparatus according to the first aspect, means for photographing a defect image by a digital camera installed in each of the plurality of steps, and defect information included in the defect image , And a means for editing the created information.

According to a third aspect of the present invention, in the apparatus according to the first or second aspect, defect information at the time of passing through each step and defect information from another department are corrected and edited. -It is characterized by having an image editing means.

According to a fourth aspect of the present invention, there is provided the apparatus according to the first, second or third aspect, further comprising means for selecting and re-editing a plurality of defect images and defect information, and storing and displaying these. Is characterized by the fact that
According to a fifth aspect of the present invention, there is provided the apparatus according to the first, second, third, or fourth aspect, further comprising a means for printing a collected defect image.

According to the present invention, various information relating to surface defects in a plurality of steps can be centrally managed. Therefore, it is possible to standardize the quality evaluation standard among the respective processes, and it is possible to solve the problem that the inspection work performed in the previous process is repeatedly performed in the next process or a defect is missed. .

Further, defects that are difficult for the inspector to determine are managed by the defect information and the photograph, so that the work of collecting the defect samples and the work of re-inspection become unnecessary. Furthermore, since there is a photographic image of each defect, there is no need for a defect limit sample, thus eliminating the task of collecting the defect sample by the cutting plate.

[0018]

Next, the present invention will be described with reference to the drawings. Drawing 1 is a figure showing an example of a manufacturing process of a cold rolled steel plate. As shown in the drawing, the hot-rolled steel sheet hot-rolled by the hot rolling mill 1 is scale-removed by the pickling device 2 and then cold-rolled by the cold rolling mill 3 to a target thickness. . The cold-rolled steel sheet cold-rolled by the cold rolling mill 3 is subjected to electrolytic cleaning, continuous annealing, and hot-dip galvanizing in an electrolytic cleaning device (ECL) 4, a continuous annealing device 7, or a hot-dip galvanizing device 9. Is done.

The cold-rolled steel sheet electrolytically cleaned by the electrolytic cleaning device (ECL) 4 is annealed in an annealing device 5 and then temper-rolled by a temper rolling mill 6 to perform shape correction, or to use an electrolytic zinc. Electroplating is performed by the plating apparatus 8. Further, the electrolytically cleaned cold rolled steel sheet is continuously annealed by the continuous annealing device 7, or
After the hot-dip galvanizing is performed by the hot-dip galvanizing apparatus 9, the hot-dip galvanizing apparatus 9 winds it up and ships it, or it is shipped after being sheared to a predetermined size by the shearing machine 11. An inspector, an optical surface defect meter, and a digital camera 21 are installed in each of the above-described cold-rolled steel plate manufacturing processes for quality control.

FIG. 2 is a block diagram of the main equipment showing the overall configuration of the present invention. As shown in FIG. 2, a front surface detector 12 and a back surface detector 13 as means for detecting the state of the front and back surfaces of the cold-rolled steel sheet are provided.
And the backside detector 13 detects defects on the front and back sides of the cold-rolled steel sheet by the CCD camera. The detected signal is corrected by the shelling correction device 31 and binarized by the binarization device 32, and thereafter, is compared with a predetermined reference value, that is, a threshold value, by the defect candidate detector 14 as comparing means, and A defect candidate point is detected by a signal exceeding the threshold.

When a defect candidate point is detected by the defect candidate detector 14, the defect image is stored in a defect image primary storage device 15 as storage means, and features such as the size and brightness of the detected defect are determined. Based on the quantity, the defect name and the defect grade are discriminated by the defect discriminating device 16 as an arithmetic mechanism. After the defects are discriminated in this way, the defect images other than the designated defect name and defect grade are deleted, and the selected defect images are stored in the secondary storage device 1.
7 is stored.

Next, information such as a defect name, a defect grade, a defect width, a defect length, and a defect position by the defect discriminating device 16 is provided as information to the defect image secondary storage device 17 and transmitted to the detection control unit 18. Can be The detection control unit 18
The sent defect image and defect information are transferred to a defect information correcting device 22 and a surface defect image display C as a display means.
The information is displayed on the RT 23 and the CRT 24 for displaying a back surface defect image, and their information is stored.

FIG. 8 shows the contents displayed by the defect information correcting device 22. When the defect reaches the position where the inspector is located, the color of the back of the device changes, and the arrival of the defect can be determined at a glance. The contents are also displayed on the CRT 23 for displaying a front surface defect image and the CRT 24 for displaying a back surface defect image. When one defect passes, the next defect is displayed. The inspector checks the defect based on the displayed defect information, and corrects the defect information using the defect information correction device 22 when the defect information needs to be corrected. There is also a method in which the display by the defect information correcting device 22 and the information by the front display CRT 23 and the rear display CRT 24 are combined to form a display screen as shown in FIG.

If it is determined that a detailed defect image is necessary, an image of the defective part is taken by the digital camera 21 and the defective image is replaced with the taken image. The digital camera 21 needs to be a close-up type camera having a resolution of 500,000 pixels or more. These pieces of information are sequentially stored in the detection control unit. When the steel plate is cut at the exit side of the line, the steel plate is reversely developed and transmitted to the tertiary storage device 25 by the defect information / defect image transmission device 19. The necessary department checks the defect information in the tertiary storage device 25.

In the case where the surface defect detection device is not installed, as shown in the block diagram of the main equipment of the RC line in FIG. 3, the defect information from the upstream process includes the surface defect image display CRT 23 and the back surface. CRT2 for defect image display
4, the defect position is collated with the defect position and the rewind amount by the rewind amount indicator 27. When the defect location is reached, the line is automatically decelerated or stopped by the automatic deceleration device and the defect is visually inspected.

When the defect information needs to be corrected, the defect information correction device 22 corrects the defect information. When it is necessary to collect a defect image, an image of the defect is taken by the digital camera 21 to determine whether to correct the defect image or to newly register the defect image. Send to device 19.

The defect information / defect image transmission device 19 reversely expands the defect information when the coil production on the line exit side is completed, and transmits this to the tertiary storage device 25. The defect information / defect image transmitted to the tertiary storage device 25 is edited again when the steel sheet passes through each process and the production is completed. The editing method is filed for each process, each customer, each defect type, and each defect grade.

Defect information to which information of a customer or the like needs to be added is obtained and input again, and is determined and edited.
Judgment of the necessity of permanent storage is made and edited again. Further, the information is used as a limit sample by organizing and editing the information in the limit sample management section.

FIG. 4 is a block diagram showing the overall system of the present invention. In each step, information sent from the defect information / defect image transmission device 19 is stored in the tertiary storage device 25. Defect information 2 from the sales department and other factories
When 8 is sent, that information is also stored in the tertiary storage device 25. These pieces of information are edited again in the defect information / image editing device 26 into information of each process, stored in the defect information / defect image final storage device 29, and printed on the display / printing device 30 of the person in charge of each department. Is done.

Therefore, the defect information is transmitted to all places in each process, and can be read out and displayed in any department and process, so that the checking operation can be performed in a timely manner, and thereby the quality can be unified. A system configuration that can be managed is realized.

FIG. 5 is a flowchart of the information processing in the present invention. As shown in FIG.
The back and front detector 13 detects the front and back surfaces of the cold rolled steel sheet, and the detected signal is corrected by the shelling correction device 31 and binarized by the binarization device 32. A defect candidate point is detected based on a signal exceeding a certain threshold and stored in the defect image primary storage device 15. The defect signal detected by the defect candidate detector 14 is used to discriminate a defect name and a defect grade by the defect discriminating device 16.

In this way, the discriminated defect information includes:
Defect image clipping device 3 from defect image primary storage device 15
The image cut out in step 4 is given, and is stored in the defective image secondary storage device 17. If there is no defective image, only the defect information is stored in the defective image secondary storage device 17.

The inspector compares the defect information with the surface defect, and when the defect information needs to be corrected, corrects the defect information by the defect information correcting device 22. When a detailed defect image is required or when image correction is required, the digital camera 21 captures the defect image.
When the coiling operation of the cold-rolled steel sheet is completed, the defect information / defect image is edited by the defect information / defect image transmission device 19 in a reverse manner to match the next process, and transmitted to the tertiary storage device 25 by the transmission device 19. .

The defect information and the defect image in the tertiary storage device 25 can be read and displayed by the transmission device 19 at any place. The defect information 28 from the sales department and other factories is edited by the defect information / image editor 26 using the coil number as a key and stored in the tertiary storage device 25.

These pieces of information are filed, organized as permanent storage, and stored and stored in the tertiary storage device 25. The permanent storage information cannot be operated unless it is a predetermined key man.

Further, such information is combined with a network system and can be displayed in any department. In addition, since it is possible to evaluate each process and necessary departments, it is possible to perform a series of quality control of surface defects, to strengthen quality control assurance, and to reduce equipment costs and labor for quality design. Can be planned.

FIG. 6 shows the defect image display CRT 2 described above.
It is an example of the display contents of 3 and 24. The reason why there is a CRT having the same contents is that the inspection positions of the front and back surfaces of the steel sheet are different, and a defect image of only the front surface or only the back surface is displayed. FIG.
Is an example of the display contents when the defect information from the defect image display CRTs 23 and 24 and the defect information correction device are combined. When a defect that is difficult to be identified on the own line is generated, the defect image is transmitted to the next process and the next process is asked for judgment.

FIG. 8 shows an example of the display contents of the defect information correcting device described above. When the defect reaches the position where the inspector is located, the color of the back surface changes, and the arrival of the defect can be determined at a glance. In addition, the color of the character is changed according to the defect grade, and serious defects that cannot be overlooked are displayed in red to call attention of the inspector.

FIG. 9 shows the display contents of the defect information at the end of the work. FIG. 10 shows an example of display contents obtained by editing information from a sales department or another factory, and filing is performed for each product type. It is effectively used when a defect is difficult to determine in each process. FIG. 11 shows an example of a defect limit sample, which is filed for each product type and each line, can be displayed anywhere, and is effectively used for the education of inspectors.

In the example described above, the defect information is corrected in the defect information display correction 22, but this may be performed by the defect image display CRTs 23, 24 instead. Further, the defect information on the front and back surfaces of the steel sheet is displayed separately by the defect image display CRTs 23 and 24, but one CR is used.
T may be substituted.

[0041]

As described above, according to the first aspect of the present invention, it is possible to integrate and manage the surface defects detected in each step, and to control the defect from the upstream step to the downstream step. A series of quality control can be performed on the occurrence state of According to the second aspect of the present invention, even if there is no surface defect meter, the defect image and the defect information are accurately created, so that accurate surface defect information can be displayed and managed as an inspection result. According to the invention described in Item 3, defect information is created more accurately, and more accurate surface defect information is displayed and managed. According to the fourth aspect of the present invention, defect information is created for each process and each product type.
More precise quality control can be performed.
According to the invention described in (1), since the defect images can be easily compared even when there is no display device, the quality control is thoroughly performed.

As described above, according to the present invention, quality control in a series of manufacturing processes of a cold-rolled steel sheet is unified, thereby reducing variation in quality among a plurality of processes and performing excellent quality control. Thus, an industrially useful effect that can reduce the work load can be obtained.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a manufacturing process of a cold-rolled steel sheet.

FIG. 2 is a block diagram of a main device section showing an overall configuration of the present invention.

FIG. 3 is a block diagram of a main device section of the RC line according to the present invention.

FIG. 4 is a block diagram showing an overall system of the present invention.

FIG. 5 is a flowchart of information processing according to the present invention.

FIG. 6 is a diagram showing an example of display contents of a defect image CRT according to the present invention.

FIG. 7 is a diagram showing another example of the display content of the defect image CRT according to the present invention.

FIG. 8 is a diagram showing an example of display contents of a defect information CRT according to the present invention.

FIG. 9 is a diagram showing another example of the display content of the defect information CRT according to the present invention.

FIG. 10 is a diagram showing an example of the display content of a defect information / defect image CRT according to the present invention.

FIG. 11 is a diagram showing another example of the display contents of the defect information / defect image CRT according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hot rolling mill 2 Pickling apparatus 3 Cold rolling mill 4 Electrolytic cleaning apparatus 5 Annealing apparatus 6 Temper rolling mill 7 Continuous annealing apparatus 8 Electrogalvanizing apparatus 9 Hot dip galvanizing apparatus 10 Recoiler 11 Shearing machine 12 Surface detector 13 Backside detector 14 Defect candidate detector 15 Defect image primary storage device 16 Defect discrimination device 17 Defect image secondary storage device 18 Detection control unit 19 Defect information / defect image transmission device 20 Surface defect meter 21 Digital camera 22 Defect information display and correction device 23 CRT for surface defect image display 24 CRT for back surface defect image display 25 Tertiary storage device 26 Defect information / defect image editing device 27 Rewind length display 28 Defect information from sales departments / other factories 29 Defect information / defect image final Storage device 30 Display / printing device for the staff in each department 31 Sailing correction device 32 Binarization device 33 Defect candidate detection device 34 Defect image cutout device

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shinichi Tomonaga 1-1-2 Marunouchi, Chiyoda-ku, Tokyo Inside Nihon Kokan Co., Ltd. (72) Inventor Shigemi Fukuda 1-1-2 Marunouchi, Chiyoda-ku, Tokyo F-term in Nippon Kokan Co., Ltd. (reference) 2G051 AA37 AB07 AC22 CA03 CA04 CA07 CA11 EA11 EA14 EB01 EB02 EC01 FA01

Claims (5)

[Claims] 1. A detecting means for detecting a surface state in each step of a steel sheet manufactured through a plurality of steps from rolling to recoil or shearing, and a comparison for comparing a detection signal from the detecting means with a predetermined reference value. Means, a calculating means for calculating a surface defect name and a surface defect grade of the steel sheet based on the surface defect signal obtained by the comparing means, and an image processing of the surface defect signal obtained by the comparing means. Storage means for recording an image obtained by the process, and display means for editing a surface defect image and defect information detected in each of the plurality of steps, and displaying the edited information simultaneously in each of the plurality of steps. A surface defect inspection device for steel sheets, characterized by the following. 2. A means for photographing a defect image by a digital camera installed in each of the plurality of steps, a means for adding defect information to the defect image, and a means for editing the created information The surface defect inspection device according to claim 1, comprising: 3. A defect information / image editing means for correcting and editing defect information at the time of passing through each step and defect information from another department.
A surface defect inspection device according to item 1. 4. The surface defect inspection apparatus according to claim 1, further comprising means for selecting and re-editing a plurality of defect images and defect information, storing and displaying them. . 5. The surface defect inspection apparatus according to claim 1, further comprising a printing unit for printing the collected defect images.