JPS6355444A - Observing method and refractory wall surface in furnace - Google Patents

Abstract

PURPOSE:To automatically observe a wearing state in a short time by radiating a light beam to two points in an observation range on the wall surface in a furnace, from the outside of the furnace, and executing an image pickup to the wall surface by two sets of image pickup devices. CONSTITUTION:The light beam is radiated to two points in a block which necessitates an observation to the inside of a furnace 1, and the attitude zoom quantity of an image pickup device 3 is adjusted by a reference position deciding part 4, an attitude control part 5, etc., so that a reference light spot S is positioned in the same part on both screens of two sets of image pickup devices 3 installed at a prescribed interval, by which the respective images are recorded in an image reading part 7. Subsequently, these images are inputted as similar variable density patterns at every scanning line into a computing element, and the deviation amount of its peak part is detected and recorded. After a detection related to all the screens is ended, the detected deviation quantity is superposed onto one image, and stores as information in a three-dimensional direction, on the screen. In such a way, it is unified with the same deviation amount range at every prescribed range centering around the maximum point in the adjacent deviation amount, and a singular point is regarded as an error and contained in its range. At this time point, for instance, the deviation amount is displayed in each separate color on a first image, superposed and outputted, and outputted as an image which can be discriminated even with the naked eye on one screen.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a method for observing the wall surface of a refractory in a refining furnace or the like in a steelworks.

(B) Prior Art When refining molten metal in the field of steel manufacturing, etc., the lifespan of refractories in the refining furnace or the like plays a large role in manufacturing costs. However, in recent years, hot spraying of refractories has become more difficult due to advances in repair technology, and in the case of localized damage to refractories, it is now possible to repair them by attaching monolithic refractories.

As a result, the life of the large furnace wall refractories is significantly extended, and along with this, the cost of the refractories is also reduced.

This type of spraying of refractories was carried out under the Japanese Patent Publication No. 58-24185.
This is done using a device like the one seen in the publication. The operator confirms the spray position with the naked eye.

For example, spraying inside a converter or blast furnace was effective if it was sufficiently observable with the naked eye.

Visual observation is impossible in small mixed pig iron furnaces, torpedo cars, etc. Therefore, a method has been proposed in which an optical scope is installed near the spray nozzle as in Japanese Patent Laid-Open No. 54-2906. However, it is not practical due to the dust caused by spraying. JP 54-791 similar to this
Publication No. 04 proposes a method in which an ITV is installed near the spray nozzle and the ITV is used for observation, but as mentioned above, this method was also not practical.

Therefore, in Japanese Patent Application Laid-Open No. 59-145479, the condition of the refractory surface is first observed, the defective parts are stored as refractories divided into addresses, and then the spraying facing the address is automatically carried out using the nozzle. We are proposing a method of repair. This method allows repairs to be made even inside the furnace, which is impossible to observe with the naked eye.

However, it is extremely difficult to observe wear and tear on the refractories inside the furnace.
On ITV television screens, the only method that has been put into practical use is one in which humans make judgments and input instructions for each address on the screen. For example, in a refractory wear measuring device using a laser distance meter, it is necessary to measure each negative point at multiple points, which takes a lot of time and is not practical for hot repair.

The above-mentioned method of measuring the distance to the refractory surface in the furnace takes a long time to measure, especially in intermittent operation furnaces such as converters. ) Cannot be paused.

Therefore, the present applicant previously proposed in Japanese Patent Application No. 83741/1983 a method of taking photographs from two distant positions and viewing the unevenness in three dimensions based on the photographs. This is also one of the methods for determining the wear and tear of refractories as described above using the human eye. This method allows you to easily smooth out unevenness.
This is an effective method because it allows observation to be completed in a very short time even immediately after a stop, and instructions for spraying can be given at the next stop. However, this method also has problems, such as requiring a lot of manual work, requiring skill due to manual work, and having many variations in judgment criteria.

(c) Problems to be Solved by the Invention The problems to be solved by the present invention are to obtain an observation method that can capture the wear and tear condition of the refractory wall inside the furnace as an image and automatically deal with it in a short period of time. It is in.

B) Means for Solving the Problems The method for observing the wall surface of a refractory in a furnace according to the present invention is a method for observing a wall surface of a refractory in a furnace using an imaging device. Irradiating light from outside the furnace, capturing images of the refractory wall using two imaging devices installed at a predetermined distance from the light point, and aligning the positions of both captured images. The above problem is solved by recording an image, detecting the phase difference between each point in both recorded images, and composing and displaying the phase difference on the image.

(e) Examples Embodiments of the observation method of the present invention will be described with reference to the drawings.

As shown in FIGS. 1 and 2, two beams of light (preferably laser beams) are applied from a light source 2 to a section in a furnace 1, such as a smelting furnace, in which a refractory wall surface needs to be observed. A reference light point is placed at the same location on both screens of two imaging devices (e.g., television cameras) 3 installed at a predetermined interval in the same plane (a plane substantially parallel to the observation target surface). The reference position determination section 4, posture control section 5, and zoom control section 6 adjust the posture and zoom amount of the imaging device 3 so that S is located, and the respective images are recorded in the image reading section 7.

Next, the recorded image is detected as a similar density pattern for each scanning line in a computing unit, and the amount of deviation of the peak portion is detected and recorded. After the amount of deviation has been detected for the entire screen, the detected amount of deviation is superimposed on one of the images and is stored as three-dimensional information on the image. The amount of deviation will be described later.

The camera is preferably a COD (solid-state image sensor) monochrome camera. All subsequent processing and signals are digitized, which reduces the memory area.

The writing unit 8 is provided with a memory for l frames, stores - hours, and transfers the storage to a memory 9 (solid magnetic disk, etc.).

Next, as shown in Figure 3, for the entire screen, centering on the point with the largest amount of deviation among the neighboring amounts (separated into + side deviation amount and one side deviation amount), It is integrated with the same deviation amount range, and the singular point is regarded as an error and placed within that range. At this point, for example, it is possible to display the amount of deviation on the screen in different colors on the first image and output it in an overlapping manner so that the image can be output as an image that can be discerned with the naked eye on a single screen.

When performing automatic spraying, the spraying device is instructed to locate the position on the image in which the amount of deviation is greatest, and the spraying device is instructed to spray at that position. The position setting can be determined by coordinates with respect to the initial reference point position of the laser beam.

For example, when a refractory wall surface is partitioned by the method described in Japanese Patent Application No. 61-83741, the laser beam is applied to fixed positions of each partition (for example, the upper left corner and the lower right corner), and the spraying is carried out at the indicated position. can be instructed.

For example, the bottom of the converter furnace is the part where the refractory wear is most severe, centering on the bottom blowing tuyere. In addition to spraying, it is now possible to replace the furnace bottom, but the furnace wall may suddenly melt due to the progress of spalling in one area, and there is a risk of a hot water leakage accident. Management is extremely important.

First, after extracting all the molten steel 5 slag from the converter, turn the converter toward the measuring instrument (normally horizontal is preferable), and then place the measuring instrument at a viewing position that covers the entire bottom of the furnace with a laser beam. Place two points on the top left and bottom right. The laser beam is an Ar laser device with an output of 2 W, which is divided into two parts by a spectrometer, and the operator determines the irradiation position using two television cameras placed approximately 1.8 m apart. The direction, tilt, and zoom amount of the camera are automatically adjusted so that the light spot of the laser beam is placed at a fixed position in the upper left and lower right, and when the adjustment is completed, the images from each camera are stored in the recording device ( 1st
figure).

Next, the laser beam is applied to each control section (for example, the bottom of the hearth is divided into four), and then the television camera is automatically adjusted to record an image.

After approximately 3 minutes for initial instrument adjustment, the time required to record a single image is approximately 2-3 minutes, total (5 images x
2) takes 18 minutes. This recording device can be used to adjust the posture of the camera, adjust the zoom, and even store images using a personal computer equipped with a Heart 9 disk.

After the on-site observation is completed, while the converter is being blown again, the computer mentioned above is connected to a large processor, and the recorded images are read out and analyzed one by one.

The analysis procedure will be explained below with reference to FIG.

■ Average /I61 to /163 of the noise removal scan line and use the result as the first
Then, the average of 2 to /164 is used as a second scanning line, and thereafter, it is sequentially leveled to reduce the influence of noise.

■ Screen reduction/base point adjustment Cut certain data on the top, bottom, left and right sides of the screen, and discard unstable parts (Figure 4 (A)). The truncation criteria at this time is
This is done so that the laser beam spot position remains constant. This is because adjustments made by the imaging device cause minute errors.

■ Phase difference detection a, comparing the scanning lines at the same location in the images of the left and right imaging devices,
First, the positions of the maximum and minimum peak positions on each scanning line are detected, and the amount of deviation of this position is recorded as the amount of deviation at the peak position. Next, each maximum peak position on the left side of the peak position is found, and the amount of deviation is similarly recorded.

Here, the amount of deviation refers to the deviation distance when the reference laser beam spot position (one of the two) is taken as the zero point. For example, if it shifts to the left side of the zero point, the amount is represented by ■, and if it shifts to the right side, the amount is expressed as e. Then, it is recorded as a value at the scanning line signal position of the reference image of either of the two images.

Differential processing is performed on the b5 scanning line, and an approximate location of the degree of change is searched for as the degree of change in density. At this time, since there are several peak points, the amount of change between them is searched and the amount of deviation is recorded.

c5 The amount of deviation is given by assuming that many deviation amounts recorded in the above processing are positive, and the unrecorded position is an average change during that time.

d. Coloring is displayed (image composition) The area between the maximum deviation amount on the side and the maximum deviation amount on the θ side on the entire screen is divided into 10 equal parts, and the color corresponding to each deviation amount is, for example, orange for the ■ side, O The side is blue, divided into shading and displayed on the screen, and the screen and the reference image (monochrome) are superimposed and displayed (FIG. 4(C)).

(2) The above processing is performed on the five images, and each composite image is sequentially output according to the operator's request, so that it is possible to easily determine the position where spraying is required next time. (Figure 4 (Bl).

■Options/Image Synthesis When displaying the composite image obtained by the above processing on a CRT, a second image is added on top of the entire image.
~ The fifth image is copied at a different scale, and the oirator manipulates the position and scale to superimpose it. After that, 2nd to 5th
If the image is replaced with the first image and displayed, the entire image can be displayed in detail (Fig. 4 (El). For example, the image may be saved as a material for furnace layer management. Spraying is performed on the repaired area. The image can also be recognized at a glance.

■ After about 30 minutes of time image processing, based on the 5 screens,
Spraying indicates the position. After that, about 20 to 3
After running for 0 minutes, the screen is summarized on one screen and is used as a recording board.

(f) Effects According to the present invention, the following effects can be obtained. '■ Conventionally, the amount of wear at the bottom of the furnace was measured by heating the furnace for about 30 minutes every 25 to 50 charges, and measuring the amount of wear on the refractories inside the furnace at several points using a laser distance meter, as well as by visual observation. , the operator was writing down the unevenness in the record book, but the downtime was 18.
minutes, allowing for more detailed and accurate records. Furthermore, observation using a laser distance meter only requires measuring one point in one measurement, and by using the reference point laser beam as it is for distance measurement, the required time can be accomplished within the image recording time.

■ Spraying can save time and improve planning. Since the spraying area can be accurately known in advance, the spraying work can be started immediately after the furnace is shut down, and there is no need to reconfirm the spraying area after the furnace is shut down. Furthermore, the amount of spraying can be roughly estimated,
The time required for spraying can be estimated, and adjustments can be made in advance with previous and previous processes, eliminating process confusion.

■ The wear layer of the furnace body becomes more accurate, and by overlapping the five images, various analyzes such as checking the effectiveness of spraying and detecting areas where wear is likely to occur can be performed using mechanical processing.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a schematic configuration of the method of the present invention. FIG. 2 is an explanatory diagram when the method of the present invention is applied to a refining furnace. FIG. 3 is an explanatory diagram showing a schematic configuration of the present invention in relation to FIG. 1. FIG. 4 is an explanatory diagram of image processing. 1: Refining furnace 2: Light source 3: Imaging device Patent applicant Sumitomo Metal Industries, Ltd. (5 others)

Claims (1)

[Claims] A method of observing a refractory wall surface inside a furnace using an imaging device includes irradiating light from outside the furnace to two points within the observation range of the wall surface inside the furnace, and placing the light points at a predetermined interval as a reference. The following steps are required: capturing images of the refractory wall surface using two imaging devices, aligning the positions of both captured images, recording both images, detecting the phase difference between each point in both recorded images, and A method for observing a wall surface of a refractory in a furnace, which comprises displaying a phase difference by composing and displaying the phase difference on the image.