JP2001025851A - Method and instrument for automatically detecting abnormal state in molten metal treating equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely detect the development of such abnormal state as to the leakage of molten metal from an image obtd. by picking up the image of the operational state in molten metal treating equipment. SOLUTION: In an automatical detecting instrument of the abnormal state, a CCD camera 10 for picking up the image of the operational state in the molten metal treating equipment, a means for discriminating respective colors in the picture elements constituting the obtd. image, a means for calculating the number of the image elements showing a specified color contained in a prescribed range on the image based on the this discriminated result and an image processor 12 having respective functions as the means for deciding as the abnormal state in the case the number exceeds the predecided reference number.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an apparatus for handling molten metal, particularly in a facility for handling molten metal, such as a refining or casting factory, in which the operating state of the equipment is imaged using an imaging means such as a CCD camera, and the result of the imaging is obtained. By judging whether the normal state or the abnormal state by performing image processing on the obtained image, etc., when automatically detecting abnormal situations such as abnormal leakage and dripping of molten metal without relying on human visual monitoring, The present invention relates to a method and apparatus for automatically detecting an abnormal situation in a molten metal handling facility, which is preferably applied.

[0002]

2. Description of the Related Art An abnormal situation such as abnormal leakage and dripping of molten metal generated in a molten metal handling facility such as a refining or casting factory handling molten metal is conventionally detected by an operator by visual monitoring or by thermoelectric detection. A number of equal sensors have been arranged, and for example, a method has been used in which a detection is performed based on a disconnection caused by scattering and adhesion of a molten metal to a thermocouple.

However, in response to the increasing demand for automation of production equipment in recent years, the number of personnel has been reduced everywhere, and an exclusive use for mainly monitoring the extremely rare occurrence of abnormalities in the molten metal. Since there is almost no staff available, normal monitoring of abnormalities is usually performed while the equipment is operating, so work is concentrated in a series of continuous operations, such as at the start. At a peak time, attention to abnormality monitoring is lacking, and as a result, the discovery of an abnormal situation may be delayed, resulting in large damage to the equipment.

In the above-described method in which a large number of sensors such as thermocouples are arranged, a large number of sensors must be arranged near a place where molten metal is easily scattered. It is difficult to maintain and manage the above sensors, and it is also difficult to make the equipment inexpensive in terms of cost.

Therefore, as another method, for example, Japanese Unexamined Patent Publication No.
At 0-71453, a CCD camera is placed near the exit of the mold, the imaging screen is divided into a plurality of sections, and image processing is performed to monitor local temperature changes on the slab surface. Has been proposed. In this method, specifically, the average luminance of each section obtained by dividing the image into a certain size is calculated, and the calculated average luminance is compared with a specific threshold to determine whether there is an abnormality.

[0006]

However, in the method disclosed in Japanese Patent Application Laid-Open No. Hei 10-71453, although the sensitivity is improved when the area is set small, the method is easily affected by disturbance or mere passing of a splash. Conversely, if the area is set to be large, the influence of disturbance or the like can be reduced, but on the contrary, the sensitivity is reduced, so that there is a problem that it is difficult to put this method to practical use.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and it is an object of the present invention to reliably detect the occurrence of an abnormal situation of molten metal from an image obtained by imaging the operation of a molten metal handling facility. It is an object of the present invention to provide a method and an apparatus for automatically detecting an abnormal situation of molten metal that can be performed.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a method for automatically detecting an abnormal situation in a molten metal handling facility, wherein the operation state of the molten metal handling facility is imaged, and the colors of pixels constituting the obtained image are discriminated. Then, the number of pixels representing a specific color included in a predetermined area on the image is calculated based on the determination result, and when the number exceeds a predetermined reference number, it is determined that an abnormal situation has occurred. It is a solution to the problem.

According to the present invention, there is further provided an automatic detecting apparatus for detecting an abnormal situation in a molten metal handling facility, which includes means for imaging an operation state of the molten metal handling facility and means for discriminating a color of a pixel constituting an obtained image. Means for calculating the number of pixels representing a specific color included in a predetermined area on the image based on the determination result, and means for determining an abnormal situation when the number exceeds a predetermined reference number. ,
With the provision of the above, the above-mentioned problem is solved similarly.

That is, in the present invention, the operation state of the molten metal handling equipment is imaged by an image pickup means such as a CCD camera, and an image obtained as an image pickup result is subjected to image processing, so as to be related to an abnormal state of the molten metal. The pixels that display a specific color are extracted and the number of pixels is determined to be normal or abnormal, so that the occurrence of abnormal situations such as abnormal leakage or dripping of molten metal can be visually observed by humans. Detection can be automatically and reliably performed without relying on monitoring, and the cost of the detection equipment and its operation can be reduced.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a block diagram showing an outline of a system for automatically detecting an abnormal situation of a molten metal applied to one embodiment of the present invention.

The automatic detection system (apparatus) of the present embodiment
Is an image of the operating state of a molten metal handling facility.
A CD camera (imaging means) 10 and the colors of the pixels constituting the obtained image are each determined, and the number of pixels representing a specific color included in a predetermined area on the image is calculated based on the determination result. An image processing apparatus 1 that performs processing such as determining an abnormal situation when the number exceeds a predetermined reference number
2 is provided.

In the above system, since the CCD camera 10 is also used for monitoring, an image signal is also input to the monitoring CRT 16 via the distributor 14. Is connected to the development CRT 20, and a video signal is output from the video 18 to the image processing device 12. In the above system, the image processing device 12
As a result of the image processing by, when it is determined that an abnormal situation has occurred,
An alarm is issued to the operator by the patrol light 22.

The system of the present embodiment is specifically applied to monitoring of the operating state of a continuous casting facility as shown in FIG. In this continuous casting facility, molten steel (molten metal) M stored in a ladle 24 is injected into a tundish 28 from a long nozzle 26, and the tundish 2
8 is injected into the mold 30 through the I / M nozzle 29. When the molten steel M injected into the mold 30 is cooled from the surroundings to form a solidified shell, the molten steel M is guided by the guide rolls 32 in a molten state, and is finally sequentially extracted as a completely solidified slab. Then, it is cut to a predetermined length on the downstream side and carried out.

In the continuous casting facility, the mold 30
The CCD camera 1 which is also used for monitoring as described above is located at a position where an image of the lower segment can be taken.
The camera 10 detects a breakout trouble occurring below the mold 30.

FIG. 3 shows an image of molten steel leakage due to a breakout trouble as an example of abnormal leakage of molten steel M in the continuous casting facility targeted for detection in the present embodiment. As for the breakout trouble, various detection methods have been established for those restricted in the mold 30 and each method has been put to practical use. However, the solidified shell is broken at a portion below the mold 30. In the case of the breakouts occurring at the three locations, methods other than visually monitoring and finding the scattering of molten steel by the operator have not been put to practical use.

FIG. 4 shows an image of a captured image obtained by the CCD camera 10 when a breakout trouble occurs. The imaging range in this case may be arbitrarily set according to a range in which molten steel may leak from the equipment, and may be divided into a plurality of ranges.

The object to be imaged is the segment portion of the secondary cooling zone of the continuous casting facility as described above, and this portion is imaged by the camera 10 from an external safe place. In this imaging part, usually, the lighting is made dark by not installing the lighting, so that the image of the breakout can be obtained as an image in which the sparks of the fireworks fall in the dark as shown in FIG. Can be. However, the method of imaging is easy to automatically detect by adjusting the aperture of the camera and taking a dark image according to the actual situation of the equipment, or by intentionally unifying the color of the surrounding equipment to a specific color. Needless to say, this may be done. If a breakout occurs during imaging under such conditions, an image in which sparks of fireworks suddenly occur in the dark as shown in FIG. 4 is obtained.

In the present embodiment, for an image obtained by imaging with the CCD camera 10, a pixel of a specific color is set in a predetermined area in the imaging range as shown in FIG. In a manner similar to the occurrence of more than a predetermined number of references, it is determined and detected that molten steel has leaked due to a breakout trouble.

The predetermined area is set in advance, and the specific color is determined and set in advance based on an image obtained by actually capturing a breakout. In order to determine whether a color is a specific color, when comparing with a current image, R, G, B
These three primary colors may be used individually, or intermediate colors other than the primary colors may be used.

More specifically, the color of the molten metal is decomposed into the three primary colors and intermediate colors from the image obtained at the time of the breakout, and the luminance value of each color is obtained. Defined as a specific color. The number of pixels of such a specific color present in a predetermined area in the imaging range,
Save as basic data for determining breakout. In monitoring the actual operation, the luminance value of each color for determining that the color of the pixels constituting the captured image is the same color as the specific color is relative to the luminance value of the specific color. You may set an allowable range of ± some%.

When the breakout is actually determined and detected based on the basic data, the number of pixels of a specific color existing in the predetermined area obtained as the basic data according to the equipment is determined. For example, a number considering an arbitrary safety factor such as 90% or 80% is set as a reference number, which is used for actual automatic determination.

With the above-described configuration of the automatic detection system of the present embodiment, a technique for detecting a breakout trouble caused by the breakage of the solidified shell in the segment below the mold 30 could be established. .

[0025]

[Example] Mold size: 600-165
Using a vertical bending type continuous casting equipment of 0 mm and thickness of 200 to 260 mm, carbon concentration of 0.20 to 0.40 wt%
The present invention was applied to continuous casting of high carbon steel, and its effect was investigated.

The surveillance image was image-processed into 80 × 100 pixels, and the color of each pixel was divided into three primary colors of RGB and compared with a specific color obtained from the color of molten steel at the time of actual breakout.
Here, the luminance of the three primary colors of the specific color is 95% for R,
G is 70%, B is 5%, and ±
The number of pixels in the range of pixels was counted as 5% as a specific color, with 5% as an allowable range.

The image processing apparatus was programmed to determine that a breakout had occurred when the counted pixels were 5% or more of all the pixels, and to issue an alarm.

Without applying the present invention, an ITV (industrial
When the operator visually observed the monitoring image of the slab under the mold 30 by the television, the operation trouble became large because the judgment of the breakout occurrence was delayed in 10% of the breakout occurrence charge.

On the other hand, when the present invention is applied, since the occurrence of breakout can be automatically detected at the initial steel leakage stage in all of the breakout occurrence charges, an action for immediately reducing the casting speed may be taken. And operation troubles were reduced. Further, when the present invention was applied, there was no occurrence of so-called erroneous detection that a normal state was erroneously detected as a breakout occurrence.

According to the embodiment described in detail above, the operation state of the continuous casting facility is imaged using the CCD camera 10,
Since the normal state and the abnormal state are determined by performing image processing on the image of the obtained imaging result, the detection of abnormal situations such as abnormal leakage or dripping of molten steel, without relying on human visual monitoring, The automatic detection can be performed automatically, and the automatic detection system can be installed and operated at low cost.

In this embodiment, since the camera for monitoring and the CRT for monitoring use a system which has already been introduced for operator monitoring, the image of the existing monitoring camera is distributed. Since the present invention can be applied to the automatic detection by the method, the equipment can be further inexpensively manufactured.

Although the present invention has been specifically described above, the present invention is not limited to the above-described embodiment, and can be variously modified without departing from the gist thereof.

For example, in the above-described embodiment, an example of a continuous casting facility has been described as a facility for handling molten metal. However, the present invention is not limited to this and may be a refining facility or the like.

In the above-described embodiment, an example in which the result of the image processing is warned to the operator by the patrol light 22 has been described. However, in the case of a continuous casting facility, the discharge opening of the tundish 28 is automatically adjusted to the full value. The casting speed may be reduced urgently by closing.

[0035]

As described above, according to the present invention,
An occurrence of an abnormal situation of the molten metal can be reliably detected from an image obtained by imaging the operating state of the molten metal handling equipment.

Further, if necessary, the equipment can be automatically stopped using the result of the automatic detection, so that it is possible to realize accurate abnormality detection in which no human error can intervene, and to reduce damage. There is also an advantage that the equipment can be minimized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an outline of an automatic detection system applied to an embodiment according to the present invention.

FIG. 2 is an explanatory view showing an outline of a continuous casting facility to which the above automatic detection system is applied.

FIG. 3 is an explanatory view showing an image of a breakout of molten steel generated in the continuous casting facility.

FIG. 4 is an explanatory diagram showing an image of an image of a portion where a breakout has occurred;

[Explanation of symbols]

 Reference Signs List 10 CCD camera 12 Image processing device 28 Tundish 30 Mold 32 Guide roll M Liquid steel B Breakout

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4E004 MC11 5B057 AA17 BA02 BA30 CA01 CA08 CA13 CB01 CB08 CB13 CC03 DA13 DA16 5C086 AA42 BA17 CA28 CB36 DA07 DA33 EA11 EA23 EA45 FA12

Claims (3)

[Claims] An image of an operation state of a molten metal handling facility is taken, colors of pixels constituting an obtained image are discriminated, and a pixel representing a specific color included in a predetermined area on the image is determined based on a result of the discrimination. A method for automatically detecting an abnormal situation in a molten metal handling facility, wherein the abnormal situation is determined when the number exceeds a predetermined reference number. 2. The method according to claim 1, wherein the specific color is a luminance value of three primary colors of R, G, and B or a plurality of intermediate colors constituting a color of the molten metal obtained from an image of an actual abnormal situation. A method for automatically detecting an abnormal situation in a molten metal handling facility, characterized in that it is determined in advance based on the base. 3. A means for photographing an operation state of a molten metal handling facility, a means for discriminating a color of a pixel constituting an obtained image, and a specification included in a predetermined area on the image based on the discrimination result. Means for calculating the number of pixels representing a color, and means for determining that an abnormal situation has occurred when the number exceeds a predetermined reference number. Automatic detection device.