JPH07117501B2 - Steel plate surface defect concentration inspection device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel sheet surface defect concentration inspection apparatus capable of integrally performing quality control of steel sheets processed in a plurality of steps.

[0002]

2. Description of the Related Art In a steel sheet manufacturing facility, a flaw inspection for quality assurance is performed over almost the entire surface. And if you go through multiple processes before shipping as a product,
It is necessary to inspect each process because the defect generated in the previous process may affect the process in the next process and it is necessary to know in which process the defect occurred. Conventionally, it has been customary that an inspection facility and an inspector are arranged in each process, and each inspector individually makes an inspection and makes a judgment.

On the other hand, as a method for inspecting defects on the surface of a steel sheet,
The surface of the steel sheet conveyed in the line is scanned in the width direction with a laser beam, the reflected wave is converted into voltage intensity by a photoelectric conversion element such as a CCD element, and the presence / absence of a flaw is determined from this signal data, and the examiner A system for issuing an alarm or the like has already been established (see JP-A-63-62825, etc.).

[0004]

[Problems to be Solved by the Invention] When individual inspectors individually inspect as described above, the quality evaluation between each process may be inconsistent, and in some cases, incomplete communication of information may occur. Depending on the situation, there were cases where the work was duplicated or a confirmation error was made. Further, according to the above-described optical inspection device, the surface roughness and the background color are different depending on the steel type and heat treatment specifications, so it is necessary to change the defect evaluation reference value depending on the product. For this reason, the inspection device of each process must have a file of the reference value, which tends to increase the equipment cost and make adjustment difficult.

The present invention has been devised in order to eliminate such disadvantages of the prior art, and its main purpose is to unify quality evaluation in a series of processes to achieve quality among a plurality of processes. While reducing the variation in evaluation,
An object of the present invention is to provide an improved steel plate surface defect concentration inspection device that does not have a reference value file for each process.

[0006]

According to the present invention, such an object is to provide an identifying means for identifying the surface state of a steel sheet, and a comparing means for comparing an output signal from the identifying means with a predetermined reference value. , The signal determined to be a surface defect by the comparison means is 2
As an apparatus for concentrating and inspecting surface defects detected in a plurality of steps each having a storage means for recording in the form of a three-dimensional image, an image signal output from the storage means in each step Display consisting of a judgment means for selecting based on a judgment value preset according to the steel type to be processed or external information, and a plurality of screens for simultaneously displaying a plurality of images selected by the judgment means And means for providing the same.

[0007]

According to such a configuration, various information regarding surface defects (defects) in a plurality of steps can be unified and managed. Therefore, it is possible to eliminate the inconvenience that the quality evaluation standards between the processes are consistent and the inspection work already performed in the previous process is repeatedly performed in the next process or the defect is overlooked. In addition, a file of evaluation reference values according to the steel type and heat treatment specifications can be stored in one place.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be described in detail below with reference to specific embodiments shown in the accompanying drawings.

FIG. 1 shows the structure of a steel sheet surface defect concentration inspection device according to the present invention. This system is, for example, for unifying quality control between a plurality of processes involved in manufacturing a cold-rolled steel strip,
An optical surface defect inspection device 1-1 to 1-n is provided in each process.

The surface defect inspection devices 1-1 to 1-n are He-Ne laser oscillators 2 for sweeping and irradiating a laser spot radiated toward the surface of the strip in the width direction, and the reflected light from the He-Ne laser oscillator 2. A pipe receiver 3 that outputs a voltage signal photoelectrically converted by light receiving elements such as photomultipliers provided at both ends of the pipe, and a predetermined flaw judgment after converting this voltage output into a differential waveform by a differentiating circuit A comparator 4 that determines the presence / absence of a flaw by comparing it with a value, an image processing unit 5 that binarizes a voltage output and converts it into a two-dimensional image, and an image corresponding to a flaw detection trigger signal from the comparator 4. And an image buffer memory 6 for recording. In addition,
The flawed portion judged here includes spot-like portions and small defects such as scratches.

Surface defect inspection apparatus 1-1 to 1-n in each step
The defect portion information output from is input to the centralized judgment board 7 having an integrated judgment function, and only the information on harmful defects is selected according to the evaluation reference value corresponding to the steel type and heat treatment specifications provided by the upper CPU 8, It is stored in the display buffer memories 9-1 to 9-n for each process. The harmful flaw information stored in the display buffer memories 9-1 to 9-n is distributed to the distributor 10
At the same time, the data are simultaneously displayed on a plurality of CRT displays 11 installed in the control room in accordance with a predetermined priority order. At the same time, the sounding device 12 notifies the approaching of the flawed portion by a sound signal.

In the control room, one inspector I constantly monitors a plurality of CRT displays 11, and if necessary, gives an instruction for visual confirmation to an operator O on the line side of each process and a visual confirmation. Give instructions to change operating conditions.

[0013]

As described above, according to the present invention, the surface defects detected in each step can be integrated and judged, and a single inspector can simultaneously monitor a plurality of steps. Various information regarding quality control in the steel plate processing step can be integrated and managed. Therefore, it is possible to minimize the variation in quality evaluation between each process, and it is possible to eliminate the inconvenience that the inspection work already performed in the previous process is repeatedly performed in the next process or the defect is overlooked. Moreover, since the data file that serves as the standard for quality evaluation according to the steel type and heat treatment specifications is stored in one place, the facility cost related to this can be reduced.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a steel sheet surface defect concentration inspection device based on the present invention.

[Explanation of symbols]

 1-1 to 1-n surface defect inspection apparatus 2 laser oscillator 3 pipe receiver 4 comparator 5 image processing unit 6 image buffer memory 7 centralized judgment panel 8 upper CPU 9-1 to 9-n display buffer memory 10 distributor 11 CRT Display 12 Sounder I Examiner O Operator

Claims (1)

[Claims] 1. A discriminating means for discriminating a surface state of a steel sheet, a comparing means for comparing an output signal from the discriminating means with a predetermined reference value, and a signal for discriminating a surface defect by the comparing means.
A device for concentrating and inspecting surface defects detected in a plurality of steps, each having a storage means for recording in the form of a three-dimensional image, and an image signal output from the storage means in each step, Judgment means for selecting based on a judgment value preset according to the type of steel processed in each step, or external information, and a plurality of screens for simultaneously displaying a plurality of images selected by the judgment means A steel sheet surface defect concentration inspection device, comprising: