JP3358537B2 - Automatic deceleration method and apparatus for defect handling in continuous line - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for automatically decelerating a continuous line when performing a visual inspection by a human based on defect information of a surface defect meter used for surface inspection of a cold-rolled steel sheet.

[0002]

2. Description of the Related Art The ability to detect surface defects on a steel sheet is most excellent in a human visual inspection if a static inspection is performed over a long time.
However, there are two types of defects that are easily visible visually and defects that are hardly visible. Which of the above is different depending on the type of defect, and also between the same defect type and the defect class. In addition, many defects are likely to occur at the edge of the steel sheet, but the defect at the edge deteriorates the detection ability by visual inspection. Therefore, while the steel plate is running, the capability of detecting defects by human visual inspection is significantly reduced.

[0003] When a steel plate is running, the defect detection capability of the surface defect meter for sporadic surface defects is significantly superior to that of humans. Therefore, the detection of sporadic surface defects relies on a surface defect meter. However, the defect detection accuracy of the surface defect meter largely depends on the surface properties of the steel sheet. In addition, it is not in a state where the defect detection accuracy can be satisfied with respect to all the defects because a minute uneven defect cannot be detected.

[0004] Therefore, a surface defect meter and a human visual inspection are used together to inspect a surface defect over the entire length of a steel sheet. In particular, in the visual inspection, the exit line is stopped at regular intervals, and a fine unevenness defect that cannot be detected by the surface defect meter is grinded to detect the defect.

In a continuous line of cold-rolled steel sheets, an inspection table for performing a visual inspection is provided on the exit side of the line in order to detect defects generated in the line as accurately as possible. Has been installed. Since the defect detection accuracy of the surface defect meter is not in a satisfactory state, it is often necessary to visually confirm the defects detected by the surface defect meter.

However, the exit speed of the continuous processing line is high, and when a surface defect meter is installed near an inspection table, even if a defect is detected, the defect passes and cannot be visually checked.
Even if it is in time, it is impossible to visually confirm the defect due to the high speed of the line. Further, if it is installed too upstream, it is unknown when the defect reaches the inspection table, and it is difficult to visually confirm the defect detected by the surface defect meter. Further, a defect occurring from the surface defect meter to the inspection table cannot be detected.

Furthermore, in a continuous processing line, the operating conditions of the central section where the required processing is performed are the most important, and it is necessary to stabilize the line speed of the central section and to pass a stable high quality product efficiently. Indispensable for manufacturing. The exit side speed of the continuous line is restricted by the central section, and when the exit side line speed is reduced during visual inspection or the like on the exit side, it must be performed within a range that does not affect the line speed of the central section.

[0008] Under such circumstances, it is difficult to sufficiently detect defects by visual inspection on the exit side of the continuous line. For this reason, there is a situation in which after the coil is once wound around the coil, it is inserted into the next step, for example, a recoil line or a slitter line, and is visually inspected again by a human to make a final judgment on the defect.

For these reasons, Japanese Patent Publication No. 1-2677
In Japanese Patent Application Laid-Open No. 2 (1994) -207, there is proposed an automatic deceleration method for a defective portion in a slitter line which can improve work efficiency when performing a visual inspection on a slitter line based on defect information of a continuous processing line in a previous process.

[0010]

[Problems to be solved by the invention] However,
In the deceleration method disclosed in Japanese Patent No. 6772, the deceleration target speed is constant, and it is possible to cope with a defect that is easily detected visually, but cannot cope with a defect that is hard to see visually. In addition, there is a problem that the work efficiency is reduced because automatic deceleration is performed to a defect whose detection by the surface defect meter is 100% reliable.

Further, since it is assumed that a defect detected on a continuous processing line is once wound around a coil and then re-inspected on another line, there is no point in performing an effective defect inspection on a continuous processing line. Not considered.

The present invention has been made in consideration of the above problems, and a main object of the present invention is to provide an automatic deceleration method and apparatus capable of effectively performing a defect inspection on a continuous line.

[0013]

The gist of the present invention for solving the above problems is as follows.

(1) When the defect information detected by the surface defect meter on the exit side of the continuous line of the band is visually re-inspected downstream of the surface defect meter, the defect information is placed on the exit side of the continuous line of the band.
In addition, the defect marking device and the defect marking inspection downstream
Equipment for detecting defects with a surface defect meter
Defect marking on the edge of the strip using a defect marking device
To track defect information detected by the surface defect meter
And the defect marking detection device
Detecting the defect and correcting the tracking of the defect position, and automatically reducing the exit line speed to a required visual inspection speed when the defect position reaches a predetermined position downstream, automatically responding to defects in a continuous line. Method.

(2) Surface gap on the exit side of the continuous line of the band-shaped body
Visually inspect the defect information detected by the defect meter downstream of the surface defect meter
When re-inspecting, the type of defect detected by the surface defect meter
Defect class and the reliability of surface defect meter judgment
The necessity of automatic deceleration is set in consideration of the difficulty of
An automatic deceleration method for dealing with defects in continuous lines , characterized in that :

(3) Surface gap on the exit side of the continuous line of the belt-shaped body
Visually inspect the defect information detected by the defect meter downstream of the surface defect meter
Defect information detected by the surface defect meter during re-inspection
When the defect position reaches a predetermined position downstream
In addition, the defect type and defect class and the corresponding surface defect meter
Target speed considering the reliability of the vehicle and the difficulty of visual judgment
Automatic deceleration method for a defect in a continuous line , wherein the output line speed is automatically decelerated to a certain degree .

(4) Defective markin on the continuous line of the band
A marking device and a defect marking detection device downstream of it
Detects defects with a surface defect meter and provides a defect marking device.
Marking on the strip with the device and detecting it with a surface defect meter
Defect information and tracking defect information
The defect marking is detected by the
Correct the tracking so that the defect position reaches a predetermined position downstream.
Automatically reduces delivery line speed to required visual inspection speed when
An automatic deceleration method for dealing with defects in a continuous line , characterized by speeding up .

(5) The required processing is performed on the strip,
Surface defects, visually inspect the band surface,
In the production method of cold rolled steel sheet manufactured through
Prior to performing any of the above (1) to (4)
Use the automatic deceleration method described in
A method for producing a cold-rolled steel sheet, comprising automatically decelerating.

(6) The surface of the band is not provided on the exit side of the continuous line.
A surface defect meter for detecting a defect, and the surface defect meter detects a defect.
Mark that marks the edge of the strip when
King device and the defect information detected by the surface defect meter.
A tracking device that tracks the in-in position
Detect defect marking and track defect position
The defect marking detection device to be corrected and the defect position
Output line speed is detected by a surface defect meter when it reaches a predetermined position
Required visual inspection speed set based on the defect information
And a delivery speed control device that decelerates at
Automatic deceleration device that responds to defects in continuous lines.

(7) A surface defect meter for detecting a surface defect of the strip on the output side of the continuous line, a tracking device for tracking a position in the line of the defect information detected by the surface defect meter, a defect type and a defect class and the like. Of surface defect meter for
Automatic deceleration in consideration of constant reliability and difficulty of visual judgment
Means for setting necessity / unnecessity and a delivery speed control device for reducing the delivery line speed to a required visual inspection speed set based on the defect information detected by the surface defect meter when the defect position reaches a predetermined downstream position. An automatic deceleration device that responds to defects in continuous lines.

(8) The surface of the strip is not provided on the output side of the continuous line.
A surface defect meter for detecting a defect, and a defect detected by the surface defect meter.
Tracking to track the position of the defect information in the line
Equipment, defect type and defect class and corresponding surface defect meter
Deceleration target considering constant reliability and difficulty of visual judgment
The speed setting means and the defect position reach the predetermined downstream position.
When the speed reaches, the exit line speed is reduced to the deceleration target speed.
An automatic deceleration device for a defect in a continuous line, comprising an output speed control device.

(9) On the exit side of the continuous line, the surface of the band is
A surface defect meter for detecting a defect, and the surface defect meter detects a defect.
Marking device for marking a strip when
And the position of the defect information detected by the surface defect meter
A tracking device for tracking the position,
To detect defects and correct defect location tracking
Defect marking detection device and a predetermined position where the defect position is downstream
When reaching the delivery line speed is reduced to the required visual inspection speed.
Communicating <br/> automatic deceleration device defects corresponding in connection lines, characterized in that it comprises a left-side speed controller for fast.

[0023]

[0024]

[0025]

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing an arrangement of main equipment of a continuous line of cold-rolled steel sheets. In FIG. 1, a coil paid out from a pay-off reel 1 on the entry side of a continuous line is connected by a welding machine 2, and is conveyed to a central section 4 via an entry side loop car 3. In the middle section 4, annealing,
It is subjected to a plating process or the like, and is conveyed to the inspection table 10 via the output side loop car 5. After the visual inspection of the surface of the steel sheet on the inspection table 10, the steel sheet is wound around the tension reel 12 on the delivery side.
When the wound coil reaches a predetermined length, the cutting machine 11
Cut at

1, a surface defect meter 6, a defect marking device 7, a defect marking detecting device 8, and a trimmer 9 are provided. The surface defect meter 6 is installed at a position where the deceleration of the inspection table 10 can be completed when the exit line speed is at the maximum speed. The defect marking device 7 is a surface defect meter 6
When the surface defect meter 6 detects a defect, the defect marking device 7 immediately performs defect marking, and at the same time, detects the defect with the tracking device 15 based on the rotation speed of the steel sheet transport roll 13 detected by the PLG 14. Track position.

The defect marking detecting device 8 is installed immediately before the trimmer 9. The defect marking detecting device 8 detects the defect marking, corrects the defect position tracking, and further improves the defect position tracking accuracy. The defect marking is removed by a trimmer 9 after being detected by the defect marking detection device 8.

Known devices can be used for the surface defect meter 6, the defect marking device 7, and the defect marking detection device 8. For example, as a defect marking device, Japanese Patent Publication No. Sho 63
As described in JP-A-10-784, an apparatus for changing a magnetic field at a defect position using a magnetizer or Japanese Patent Application Laid-Open No. H2-2594.
As described in Japanese Patent Application Publication No. 54-54, a device for adhering ink can be used, and a device for detecting a change in the magnetic field or a device for detecting an ink adhering portion may be combined as a marking detector.

FIG. 2 is a diagram showing a system configuration of the surface defect meter 6. In the surface defect meter 6, surface defects are detected by the detectors 21 on the front and back surfaces of the steel sheet, and the signal processing unit 22 determines the defect type and defect class. Further, the surface defect meter 6 includes, in advance, a defect in which the judgment result of the surface defect meter 6 is reliable in consideration of a defect type and a defect class, a defect in which the reliability of the judgment result is inferior but which is easy to see visually, and a reliability of the judgment result. However, defects that are inferior and hard to see even visually are discriminated and set.

In the surface defect meter 6, the defect type / defect class detected and determined, and the reliability of the judgment of the surface defect meter 6 set in advance for the defect and the difficulty of visual judgment are considered, and the defect portion is determined. Necessity of automatic deceleration at the inspection table 10,
Set the deceleration target speed for automatic deceleration.

If the defect type / defect class detected and determined by the surface defect meter 6 is a defect for which the determination result of the surface defect meter 6 is reliable, the inspection table 10 does not perform automatic deceleration. Surface defect meter 6
In the case of a defect in which the judgment result of
The speed at the inspection table 10 is set to a predetermined deceleration target speed and visually inspected. When the reliability of the determination result of the surface defect meter 6 is low and the defect is difficult to see visually, the deceleration target speed is set so that the defect is stopped at the inspection table 10 and visually inspected.

Based on the target deceleration speed set by the surface defect meter 6, a deceleration command is issued to the outlet speed control device 24. The exit speed control device 24 calculates a deceleration condition and decelerates the inspection table 10 to complete automatic deceleration based on the tracking of the current speed, the target deceleration speed, and the defect position. When the defect marking detection device 8 detects a defect marking portion, the tracking of the defect position is corrected, and the deceleration condition is recalculated so that the predetermined deceleration target speed is reached when the defect position reaches the inspection table 10. Correct the deceleration speed. Also,
The exit speed control device 24 can set whether or not to perform automatic deceleration based on an instruction from the surface defect meter 6 based on the defect type and defect class detected by the surface defect meter 6.

FIG. 3 is a diagram showing an example of the reliability of a surface defect meter for each defect type / defect grade, and FIG.
It is a figure which shows the example of the difficulty of discrimination of the defect by visual inspection according to defect kind / defect grade in case of pm. 3 and 4,
For each defect type, the defect class is classified into four stages of A to D according to the degree of defect, and further classified into three stages of upper, middle and lower in each of the classes. The reliability of the surface defect meter and the difficulty of discriminating defects by visual inspection are set for each of the defect types and defect classes classified as described above. Note that the degree of defect is the smallest in A, and the degree becomes severe in the order of B, C, and D. Within each of the above sections, the degree becomes severe in the order of upper, middle, and lower.

Table 1 is a speed table showing an example of the deceleration target speed when performing the visual inspection in consideration of the reliability of the surface defect meter shown in FIG. 3 and the difficulty of the visual inspection shown in FIG. .

When the surface defect meter 6 detects a defect, the surface defect meter 10 is determined based on the defect type / defect class based on these figures and table.
Automatic deceleration is not performed for a 0% reliable defect. Also,
If the reliability of the surface defect meter is 80%, if the defect is clearly visible, the automatic deceleration target speed is set to 100 mpm.
For defects that are visible, set to 50 mpm. For a defect whose surface defect meter reliability is 80% and cannot be seen visually, the automatic deceleration target speed is set to 0 mpm.

[0038]

[Table 1]

The output speed control device 24 monitors the position of the output loop car 5 until the automatic deceleration is started after the input of the deceleration command from the surface defect meter 6, and the storage amount of the steel plate in the loop car 5 is equal to or more than a certain value. If it has increased, it is determined that the central section 4 will be affected, and automatic deceleration is not performed. In this case, since the visual inspection of the defect cannot be performed on the output side, the defect is once wound around the tension reel 12, and then the surface inspection is performed on the recoil line in the next process. In addition, an alarm is output to the alarm device 25 to the effect that automatic deceleration is not possible, to alert the inspector.

The surface defect meter 6 detects defect information,
The defect image is tracked, and a defect information display 27 and a defect image display 28 are displayed on a CRT 26 provided on the inspection table 10 before the defect reaches the inspection table 10. In addition, an alarm is output to the alarm device 25 five seconds before the defective portion reaches the inspection table 10 to notify the inspector of the arrival of the defect. For the defect information, a defect longitudinal position, a defect width position, a defect type, and a defect class are displayed so that the inspector can easily find the defect position. The inspector visually inspects the steel sheet traveling at a predetermined target deceleration speed on the inspection table 10, and accelerates the delivery side after the visual inspection is completed.

If the exit side does not accelerate after a lapse of a certain time after the completion of the automatic deceleration, or if the storage amount of the exit side loop car 5 increases to a certain value or more, an alarm to that effect is output.

FIG. 5 is an example of a display screen of the defect information displayed on the CRT 26. When the visual judgment of the inspector is positive, C
The defect information can be corrected by directly inputting from the RT 26. In addition, it is possible to input an overlooked defect of the surface defect meter 6.

The defects detected and determined by the surface defect meter 6 are visually inspected, and the results are sent to the host computer 23. The host computer 23 performs quality control for each product coil.

FIG. 6 is a diagram showing a change in the outgoing line speed when the automatic deceleration is performed.
When the output line speed is not reduced in the case of a 0% reliable defect, the case of a defect that is easy to see by visual inspection, and when the target deceleration speed is changed according to the difficulty of the visibility (for example, in FIG. , △) indicates a case where the defect is difficult to see by visual inspection and the exit side is stopped for inspection.

In the above-mentioned apparatus, the defect marking device 7 and the defect marking detecting device 8 are installed for improving the accuracy of defect tracking, but these devices may not be provided. Although the trimmer 9 is provided to remove the defect marking portion, the defect marking portion may be removed by a recoil line in the final process.

[0046]

As described above, according to the present invention,
Automatically decelerates to a speed suitable for visual inspection when defects detected by the surface defect meter reach the inspection table, eliminating the need for inspectors to search for defect positions, reducing the defect determination work load and reducing re-inspection time. Shortening is possible, and retesting efficiency can be greatly improved. The required surface defect inspection can be effectively performed in a continuous line by using both a surface defect meter and a visual inspection, so that a highly reliable surface inspection can be performed in terms of quality assurance. Therefore, conventionally, the defect detected by the surface defect meter is determined in the recoil line or the slitter line, which is the final step of the cold-rolled steel sheet, but such an operation becomes unnecessary and the step can be omitted. In addition, it is possible to greatly reduce the work time and the work load of the inspector by omitting the inspection.

Further, it is possible to detect the generated defect at an early stage, and it is possible to take a necessary defect countermeasure at an early stage.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a continuous line used for describing an embodiment of the present invention.

FIG. 2 is a diagram showing a system configuration of a surface defect meter.

FIG. 3 is a diagram showing an example of the reliability of a surface defect meter for each defect type and defect grade.

FIG. 4 is a diagram showing an example of the difficulty of detecting a defect in a visual inspection by defect type and defect grade.

FIG. 5 is a view showing an example of a display screen of defect information of a CRT.

FIG. 6 is a diagram showing a change in an outgoing line speed when automatic deceleration is performed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1-Off-reel 2 Welding machine 3 Entry loop car 4 Center section 5 Exit loop car 6 Surface defect meter 7 Defect marking device 8 Defect marking detection device 9 Trimmer 10 Inspection table 11 Cutting machine 12 Tension reel 11 Alarm device 13 Steel plate transport roll 14 PLG 15 Tracking device 16 Steel plate 21 Detector 22 Signal processing unit 23 Host computer 24 Outgoing speed control device 25 Alarm device 26 CRT 27 Defect information display 28 Defect image display

Continued on the front page (72) Inventor Shigemi Fukuda 1-1-2 Marunouchi, Chiyoda-ku, Tokyo Nippon Kokan Co., Ltd. (72) Inventor Akio Naga1-2-1, 1-2-Marunouchi, Chiyoda-ku, Tokyo Nippon Kokan stock In-company (72) Inventor Tsutomu Kawamura 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Nippon Kokan Co., Ltd. (56) References JP-A-3-118912 (JP, A) JP-A 5-346407 (JP, A) JP-A-6-714 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B21C 51/00 G01N 21/84

Claims (9)

(57) [Claims] 1. A method for visually re-inspection of defect information detected by a surface defect meter on the output side of a continuous line of a band downstream of the surface defect meter, the defect information is further provided on the output side of the continuous line of the band.
Defect marking device and defect marking detection device downstream
The defect is detected at the same time as the
Defect marking is performed on the edge of the strip using a marking device.
There, to track defect information detected by the surface defect meter
With the defect marking detection device
Detecting the defect and correcting the defect position tracking, and automatically reducing the exit line speed to a required visual inspection speed when the defect position reaches a predetermined downstream position, the method for automatically decelerating defects in a continuous line. . 2. A surface defect meter on the exit side of a continuous line of a strip.
Visually re-examine the defect information detected in the downstream of the surface defect meter
In the inspection, the defect type and defect detected by the surface defect meter
Grade and the reliability and accuracy of the
Set the necessity of automatic deceleration considering the difficulty of visual judgment
An automatic deceleration method for dealing with a defect in a continuous line. 3. A surface defect meter on the exit side of a continuous line of a strip.
Visually re-examine the defect information detected in the downstream of the surface defect meter
The defect information detected by the surface defect meter.
Racking, when the defect position reaches the predetermined position downstream,
Defect type and defect class and signal of judgment of surface defect meter for it
The deceleration target speed considering the reliability and the difficulty of visual judgment
Automatic deceleration method for a defect in a continuous line, wherein the output line speed is automatically decelerated . 4. A defect marking device on a continuous line of a strip.
A defect marking detection device is installed on the
Detect defects with a defect meter and use a defect marking device
Defect marking was performed on the strip and detected with a surface defect meter
Tracking defect information and defect marking inspection
The defect marking is detected by the output device and the defect position is traced.
Corrects the locking, and when the defect position reaches the predetermined position downstream
Automatically reduce the exit line speed to the required visual inspection speed
An automatic deceleration method for dealing with a defect in a continuous line. 5. A required process is performed on the strip, and the table of the strip is displayed.
Detects surface defects, visually inspects the surface of the band, and
In the manufacturing method of the manufactured cold rolled steel sheet, a visual inspection was performed.
Prior to the operation, the vehicle according to any one of claims 1 to 4
Automatically decelerates the outgoing line speed of the defective part by dynamic deceleration method
A method for producing a cold-rolled steel sheet. 6. A surface defect of a belt-like body at an output side of a continuous line.
Surface defect meter to be detected and when the surface defect meter detects a defect
Mark marking on edge of strip
Device and a line of defect information detected by the surface defect meter
A tracking device for tracking the inside position,
Detect defect marking and correct defect location tracking
And a defect marking detection device that
Outgoing line speed was detected by a surface defect meter when it reached the position
Reduced to required visual inspection speed set based on defect information
And a delivery speed control device for speeding up the delivery.
Automatic reduction gear for defect handling in the continuation line. 7. A surface defect meter for detecting a surface defect of a strip on the output side of a continuous line, a tracking device for tracking a position of the defect information detected by the surface defect meter in a line , a defect type and a defect class and a corresponding defect class Judgment of surface defect meter
Automatic deceleration is necessary in consideration of the reliability of
Means for setting the failure and a delivery speed control device for reducing the delivery line speed to a required visual inspection speed set based on the defect information detected by the surface defect meter when the defect position reaches a predetermined downstream position. An automatic deceleration device that responds to defects in a continuous line. 8. A surface defect of a belt-like body on the output side of a continuous line.
Surface defect meter to be detected, defect information detected by the surface defect meter
Tracking device that tracks the position of the
Location, defect type and defect class and the corresponding surface defect meter
Target speed considering the reliability of the vehicle and the difficulty of visual judgment
Degree setting means and defect position reach predetermined position downstream
When the output line speed is reduced to the deceleration target speed
An automatic deceleration device for a defect on a continuous line, comprising a side speed control device. 9. A surface defect of a belt-like body at an exit side of a continuous line.
Surface defect meter to be detected and when the surface defect meter detects a defect
Marking device for marking a strip on a web
And the position in the line of the defect information detected by the surface defect meter
A tracking device for tracking the defect mark;
The lack of detecting the king and correcting the tracking of the defect position
Defect marking detection device and the defect position
Upon arrival, reduce exit line speed to required visual inspection speed
And an automatic speed reduction device for dealing with defects in a continuous line.