JPH07175931A - Slag height measuring device - Google Patents

Abstract

PURPOSE:To detect the liquid level of slag within a slag pot and to prevent the overflow of the slag from the slag pot without being affected by slag flowing down from a furnace pot to the slag pot by providing a filtering processing deleting a slag image flowing down to the slag pot. CONSTITUTION:The image obtained by a CCD camera 2 is inputted in an image processor 3, density conversion processing is performed for the image at first and the contrast of the image is made clear. Namely, the bright part on the image is further brightened and the dark part is further darkened. Next, a filtering processing is performed for the image after a density coversion processing, continuous vertical lines are deleted and continuous horizontal lines are emphasized. Thirdly, a binarization processing is performed for the image after the filtering processing and the bright part generated by the luminance difference of one image is made white or black, or only two values of 0 or 2 as digital signals. Fourthly, a contract/expansion processing is performed for the image after the binarization processing and noise scattering on the image is deleted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects the height of slag in a slag pan when the slag generated on molten steel in a semi-molten state is received from the furnace pot with the slag pan. The present invention relates to a slag height detecting device that prevents the overflow of slag from a slag pot by detecting the occurrence of a forming phenomenon in a slag.

[0002]

2. Description of the Related Art Iron and steel are produced by melting ore or metal, which is a raw material, or scrap, at a high temperature in an electric furnace or the like. At that time, in the molten steel in a semi-molten state after melting, the impurities contained in the raw material become oxidized slag and float on the molten steel. This oxidized slag is called Noro, but it is necessary to remove it in order to secure the quality characteristics of iron and steel.

Therefore, in order to remove the slag from the furnace pot of an electric furnace or the like, the slag on the molten steel is poured into the slag pot by tilting the furnace pot or the like. However, a phenomenon called forming frequently occurs in the Noro pot during the work of flowing from the furnace pot to the Noro pot. This forming means unreacted desiliconizing agent (FeO) in slag and C in molten steel.
Is a phenomenon in which fine bubbles (CO) are generated by the reaction. A familiar phenomenon is that when you pour beer with the cup standing vertically, the bubbles of beer gradually swell.

Therefore, when foaming occurs in the pot, it causes the foam-like bulge to overflow from the pot, so that the pot cannot be poured into the pot until the forming has subsided. .
However, since it is difficult to temporarily suspend the slag receiving work, the forming sand is intentionally calmed by throwing sand for forming prevention from above the foamed slag.

At present, the occurrence of forming is mainly determined by the operator's visual inspection. Therefore, the operator monitors the occurrence of forming to insert sand, or the sand is constantly introduced to cause the occurrence of forming. This is dealt with by preventing this.

[0006] As described above, according to the method of monitoring by the operator, it is possible to confirm the occurrence of forming and adjust the input amount of sand accurately, but it is always necessary to monitor when the slag is flowing. In addition, the method of always adding sand can suppress the occurrence of forming, but it is not economical because the addition of sand causes the addition of extra sand.

Therefore, it has been desired to automate the detection of the height of the slag inside the slag pan to prevent the overflow from the slag pan and the detection of the timing of sand feeding when forming occurs.

[0008]

Therefore, an image sensor, which is one of the sensors for detecting the liquid surface level, is utilized as a means for detecting the liquid surface level of the slag in the ladle.
In the image obtained by this image sensor, the liquid level is measured by utilizing the light emission of the Noro and the brightness difference between the Noro of the imaged image and the inner wall of the Noro pot. However, in general, in such an optical liquid level detection, it is desirable that there is no object that obstructs the image to be taken in from the image sensor.
The problem was that it was difficult to detect the level of the liquid level stably because the field of view was easily obscured by the sloppy flow from the furnace pan.

The present invention has been made in view of the above problems, and an image obtained by an image sensor is
By performing the treatment, the level of the slag in the slag pot is detected without being affected by the slag that flows down from the furnace pot to the slag pot, the overflow of the slag from the slag pot is prevented, and the occurrence of forming occurs. An object of the present invention is to provide a lapping height detecting device for detecting the timing of sand feeding.

[0010]

SUMMARY OF THE INVENTION According to the present invention, the height of the slag in the sushi pot is composed of an image sensor for capturing the image in the sushi pot and an image processing unit for processing the image obtained by the image sensor. It is a detecting device, wherein the image processing section is provided with a filtering process for erasing the image of the sloppy flowing into the sushi pot.

First, an image sensor for capturing an image inside the pot is provided. The image sensor may be a commonly used one that can capture a two-dimensional image.

An image of the inside of the ladle obtained by the image sensor is input to the image processing unit. In the image processing unit, the input image is first digitized and represented as a brightness value. Then, a certain threshold value is set for the luminance value of each portion, and the image processing portion discriminates the binary value of light and dark depending on whether the threshold value is greater than or equal to the threshold value. The binary value referred to here corresponds to a screen other than the non-standard screen.

However, the image obtained by the image sensor is blocked by the slag that does not relate to the liquid surface, that is, the flow slag, due to the slag that flows down from the furnace pot. For this reason, the image of the flowing roe is treated as noise, and filtering processing is performed to cut noise.

The filtering is a process of erasing one of continuous vertical and horizontal lines in an image, and the flow slag is eliminated by making the direction of the line to be erased the same as the direction of the flow slag.

The image data after the above processing is input to the arithmetic processing unit, and the position recognized as the bright portion on the image is calculated as the height of the slag. Also, the height displacement of the slag is divided by the time to calculate the slop height speed.

Further, the signal from the image processing section is input to an alarm circuit or a sanding circuit for forming prevention. This input signal is set so that an alarm or sand throwing is performed in case of an abnormality in the sloping height speed in the image processing unit.

[0017]

According to the ladle height detector of the present invention, the image inside the ladle pan is taken in by the image sensor, and the image obtained by the image sensor is input to the image processing section. Further, the image processing section makes the brightness of the image clear,
Further filtering is performed to eliminate continuous unnecessary lines and to cut the image of the flow slag, so that the liquid level height of the slag on the screen can be accurately captured.

Further, after the above processing is performed, the position recognized as the bright portion on the image is calculated by the arithmetic processing unit as the height of the slag. Further, the height displacement of the slag is divided by time to calculate the slag height speed, and it can be determined that the forming has occurred when the slop height speed rapidly increases.

After the above image processing is performed in the image processing section, when a rapid change in the roast height speed is detected, a signal is input to the alarm circuit and a sand pan is fed to the sand throwing circuit. It is possible to support the forming by inputting the signal for sand filling.

[0020]

Embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, an electric furnace 1 for melting scrap, which is a raw material of steel, is provided with a discharge port 11 for discharging slag on a side surface of the electric furnace 1. Further, the discharge port 11 is openable and closable by an opening / closing mechanism.

A pan 20 is arranged below the discharge port 11 provided on the side surface of the electric furnace 1. The pot 20 is a cart 2 held by a rail for transportation.
It is mounted on one cargo bed and guided by the carriage 21 so as to be movable in the longitudinal direction of the rail.

A CCD camera 2 which is an image sensor is installed above the roast pan. The CC
The D camera 2 is placed so that the visual field is located in the vertical direction of the inner wall of the pot, and is arranged vertically to the inner wall, and the focus of the CCD camera 2 is aligned with the inner wall of the pot 20. There is. This aims at minimizing the variation in sensitivity at the focus by focusing the field of view from the CCD camera on the inner wall.

The image picked up by the CCD camera 2 is input to an image processing device 3 which is an image processing section.
The image processing device 3 may be a normal device that digitizes a video signal or the like and performs computer processing.

The image processing device 3 has a basic function of performing the following processing. A density conversion processing function that changes the contrast of an image, a filter processing function that erases geometrical elements such as lines, and one image in white or black.
This includes the binarization processing function for converting values, the contraction / expansion processing function for eliminating noise on the image, the pixel count processing function for counting the number of pixels, and the arithmetic processing function for calculating the level and speed from the number of pixels. , Image information can be processed using these functions.

Further, an alarm circuit 4 and a sand throwing device circuit 5 are provided, and are arranged so as to be operable upon receiving an output signal from the image processing device 3. This alarm circuit 4
Is connected to an alarm lamp, and the sand input device circuit 5 is connected to a sand input device. The sand throwing device throws sand into the inside of the pot.

Next, these operations will be described. First, in the electric furnace 1, raw material scrap is melted at a high temperature.
In the semi-molten state of the molten steel produced by this melting,
Noro is formed on the molten steel. In order to remove this slag, the existing opening / closing mechanism of the discharge port 11 is opened and the electric furnace 1 is tilted. Below the discharge port 11 is a pot 2
0 is provided, and the slag in the electric furnace 1 flows down to the slag pan 20 through the discharge port 11. The pouring is poured to a predetermined liquid level in the pouring pan.

The above-mentioned C which is arranged above the above-mentioned pot
The CD camera 2 captures an image of a predetermined position on the inner wall of the ladle. Since the captured image has a vertical field of view with respect to the inner wall of the Noro pot, if the amount of Noro increases, the liquid level will rise to the upper side in the image.

The image obtained by the CCD camera 2 is input to the image processing device 3. And first of all
The density conversion processing 31 is applied to the image to clarify the contrast of the image. That is, the bright areas on the image are brighter,
Make dark areas darker.

Next, the image 51 after the density conversion processing 31 is performed.
Then, the filtering process 32 is performed to delete continuous vertical lines and emphasize continuous horizontal lines.

Thirdly, the image 52 after the filtering process 32 is subjected to the binarization process 33, and the light and dark produced by the brightness difference of one image is white or black, that is, only the binary value of 0 or 1 as a digital signal. To

Fourth, the image 53 after the binarization processing 33.
Then, the contraction / expansion process 34 is performed to eliminate noise scattered on the image. In the contraction / expansion process 34, when the value of a predetermined point on the image is the center, the neighboring point is forcibly set to 0, and the point of 1 is set to 1. By performing this processing on the entire screen, isolated bright and dark points such as noise are erased.

Fifth, the image 5 after the contraction / expansion processing 34
The window setting 35 is set to 4. By the window setting, an arbitrarily set image range is designated.

Sixth, the image 5 after the window setting 35
5, the pixel number counting process 36 is performed. The number of pixels in the bright area within the range designated by the window setting is counted.

Seventh, the image 56 after the pixel number counting process 36 is subjected to a level / velocity measuring process 37, and the liquid level of the slag is calculated from the information obtained from the pixel count number, and The rising speed of the Noro liquid level is calculated and calculated from the temporal transition of the liquid level.

Therefore, when forming occurs and fine bubbles are generated and the liquid surface rises, the rising speed of the liquid surface is increased, and the level / velocity measuring process 37 detects it.

Further, the output signal from the image processing device 3 is inputted to the alarm circuit 4 and the sand throwing device circuit 5,
The alarm circuit 4 receives an output signal from the image processing device 3 to display an alarm signal and turns on an alarm lamp. The sand throwing device circuit 5 receives the output signal from the image processing device 3 and transmits the throwing signal to the sand throwing device to throw the sand into the pot.

【The invention's effect】

As described above, by providing the image processing device 3 with the filtering process 32, the image of the slag flowing from the electric furnace 1 shown in the image of the CCD camera 2 is treated as a continuous vertical line and erased.

Therefore, according to the embodiment of the present invention, when pouring slag from the electric furnace 1 into the slag pan 20, even if the image is blocked by the sloping slag, the condition of the liquid level of the slag inside the slag pan is determined by the CCD. It is possible to monitor with the camera 2, and it is possible to quickly respond to the occurrence of forming.

[Brief description of drawings]

FIG. 1 is an overall view of an embodiment

FIG. 2 is a block diagram of image processing according to an embodiment.

[Explanation of symbols]

 1 Electric Furnace 2 CCD Camera 3 Image Processing Device 4 Alarm Circuit 5 Sand Input Circuit 11 Discharge Port 20 Noro Pan 21 Truck 31 Concentration Conversion Processing 32 Filtering Processing 33 Binarization Processing 34 Shrinkage / Expansion Processing 35 Window Setting 36 Level / Speed Measurement Processing 37 Pixel count processing 50 Image inside Noro pot 51 Image after density conversion process 52 Image after filtering process 53 Image after binarization 54 Image after contraction / expansion process 55 Image after window setting 56 Pixel count Data obtained by processing

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display area G06F 15/68 400 A

Claims (1)

[Claims] 1. A detection device for detecting the height of slag in a pot, comprising an image sensor for capturing an image in the pot and an image processing unit for processing the image obtained by the image sensor, A slag height detecting device, characterized in that the image processing section is provided with a filtering process for erasing the slag image flowing down to the slag pot.