JPS61134611A - Instrument for measuring shape in furnace - Google Patents

Abstract

PURPOSE:To detect the local bend at the front end of a measuring lance with good accuracy by providing plural circular rings near the front end of the measuring lance and picking up the image of the movement of the lowermost point by an image pickup means having the visual vield including the lowermost point of the plural circular rings near the front end of the measuring lance provided to a self-traveling carriage which supports the rear end of the measuring lance. CONSTITUTION:A measuring lance 12 is inserted into a converter 10 and a laser beam 23 is projected by projecting parts 24, 28 to furnace wall surface 10B and a furnace base 10C. The images of the bright points 26A, 30A of the beam are respectively received by photodetecting parts 32, 34 and are fed to an ITV36, by which the images are picked up. Such operation is executed while the lance 12 is rotated around the axis by a lance driving part 22 and is moved in the axial direction so as to scan the entire inside surface of the converter by the laser beams 26, 30. The coordinates at the respective points of the profile in the furnace are thus determined in accordance with the principle of triangulation by the various coordinate positions and rotating angle. However, the deflection by gravity, etc. arise when the lance 12 is inserted into the furnace and therefore the movement of the lowermost point of the circular rings 14, 16 on the lance 12 are projected on the ITV40 and the positions of the bright points 26A, 30A of the laser beam are corrected.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to an apparatus for measuring the shape inside a furnace, and is particularly suitable for use in detecting the state of wear and tear on the refractory lining of a converter.
The present invention relates to an improvement of a furnace shape measuring device that non-contactly measures the shape of the inside of a furnace from the position of a bright spot of a laser beam projected into the furnace.

[Conventional technology]

The life of a refractory-lined furnace, for example a steelmaking furnace such as a converter, is determined by the wear and tear of the refractory lining. In recent years, along with the development of repair techniques for internal wear of refractory linings, there is a need for techniques to quickly and accurately measure the state of wear of refractories after tapping. Therefore, for example, in Japanese Patent Application Laid-Open No. 115160/1983, a measuring lance is inserted into the converter immediately after steel is tapped, and a laser beam is used by a light emitting part and a light receiving part attached to the tip of this measuring lance. A method of measuring the inner surface shape of a refractory lining has been proposed based on the principle of so-called triangulation. In this method, by rotating the measuring lance around its central axis and/or moving it in parallel in the direction of the central axis, it is possible to detect and confirm the state of erosion over a wide range of the inner surface of the refractory lining. I can do it.

[Problems to be solved by the invention]

However, in order to accurately detect the erosion position using the method proposed in JP-A-54-115160, it is necessary to keep the center axis of the measuring lance constant during each measurement or at least one measurement. However, because the furnace volume of modern converters is extremely large, the measuring lance generally does not deflect due to gravity when inserted horizontally into the converter, which is tilted at right angles after tapping. In addition, since vertical and horizontal vibrations are also added, the curved shape of the central axis of the measuring lance cannot be kept constant and changes, making it extremely difficult to perform accurate measurements in practice. In order to solve these problems, the applicant has already proposed in Japanese Patent Application No. 58-153193 a method of imaging the tip of a hollow lance using an imaging device outside the reactor, and processing and calculating the image signal to obtain the tip of the lance. From the information on the lowest end position, the curve shape of the central axis of the measuring lance at the time of detection is estimated, and this is used to estimate the curve of the measuring lance and rXvJ.
We propose a method to correct measurement errors based on . However, in the method disclosed in Japanese Patent Application No. 58-153193, the position of the lowest point of the tip of the measuring lance is detected, so it is difficult to accurately detect local bending of the tip of the measuring lance. was difficult. .

[Purpose of the invention]

The present invention was made in order to solve the above-mentioned conventional problems, and it is possible to detect the local bending of the tip of the measuring lance with high accuracy, and therefore to perform highly accurate correction according to the bending of the measuring lance. The purpose of the present invention is to provide a device for measuring the inside shape of a furnace.

[Means to solve the problem]

The present invention provides a furnace shape measuring device for non-contact measuring the shape of the inside of a furnace from the position of a bright spot of a laser beam projected into the furnace. A measuring lance that is inserted into the furnace and is rotatable around its axis; a self-propelled cart that supports the rear end of the measuring lance and is movable in the axial direction of the measuring lance; and movement of the self-propelled cart. a moving displacement detection means for detecting displacement; a lance driving means disposed on the self-propelled cart for rotating the measurement lance; a rotation angle detection means for detecting a rotation angle of the measurement lance; A light projecting means for projecting a laser beam into the furnace at a set angle, arranged on the measurement lance; a first imaging means for capturing an optical image obtained by the light receiving means; and a field of view including the lowest point of a plurality of rings near the tip of the measuring lance disposed on the self-propelled cart. and a second imaging means for imaging the movement of the lowest point, and correcting the position of the laser beam bright spot detected by the first W1 means with the amount of bending of the measuring lance detected by the second imaging means. The above object is achieved by comprising a signal processing means for calculating the shape of the furnace interior from the true position of the laser beam bright spot obtained by the above-mentioned measurement, and the rotation angle and movement displacement of the measuring lance.

[Effect]

In the present invention, when detecting the amount of bending of the measuring lance, a plurality of rings are arranged near the tip of the measuring lance, and the measuring lance is arranged on a self-propelled cart that supports the rear end of the measuring lance. A second imaging means having a field of view including the lowest points of the plurality of rings near the tip of the lance detects the movement of the lowest points.
Since the measurement lance is imaged, the local amount of bending at the tip of the measuring lance can be detected with high accuracy. Therefore, the position of the laser beam bright spot detected by the first image carrier that obtains the optical image inside the furnace can be corrected by a high degree of 11 degrees, and the true position of the laser beam bright spot, that is, the shape of the inside of the furnace, can be corrected with high precision. It can be detected well.

【Example】

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a brick residual thickness measuring device for a converter to which the present invention is applied will be described in detail below with reference to the drawings. In this embodiment, as shown in FIG. 1, two rings 14 and 16 are arranged near the tip of the converter 10, which is inserted from the furnace mouth 10A into the converter 10 tilted at right angles after tapping. , includes a measuring lance 12 rotatable about a central axis. The rear end of the measuring lance 12 is connected to the measuring lance 12 via the lifting table 20.
It is supported by a self-propelled trolley 18 that is movable in the central axis direction. The self-propelled trolley 1B has its advancing and retreating positions, that is,
A forward/backward position detector 19 for detecting a forward/backward position x of the measuring lance 12 is provided. A lance drive mechanism 21 for rotating the measuring lance 12 around its central axis is disposed on the elevating table 20. The lance drive mechanism 21 has a rotation angle θ of the measuring lance 12.
A rotation angle detector 22 is provided to detect the rotation angle. Laser beams 26 and 30 are applied to the tip and central side surfaces of the measuring lance 12 at set angles to the furnace wall surface 1 of the converter 10, respectively.
Light projecting units 24 and 28 are provided to project light onto 0B or the furnace bottom surface 10C. Further, the light projecting section 24 is provided on the side surface of the measuring lance 12.
．． Light receiving sections 32 and 34 are provided to obtain an optical image of the furnace wall surface 10B or the furnace bottom surface 10C in fields of view 32A and 34A including the laser beam bright spots 26A and 3OA caused by the laser beams 28 and 3OA.
1 The self-propelled trolley 18
A laser oscillator 23 that emits a laser beam is installed at the rear of the
is installed. Note that the laser oscillation 123 can also be fixed to the floor. The light emitted 1!624.28 is transmitted to the laser oscillator 2 by an optical transmission fiber 29 housed in the measuring lance 12.
3 is connected. At the rear end of the measuring lance 12, the light receiving section 32.34 is provided.
A first industrial television camera (hereinafter referred to as ITV) 36 is disposed to convey an optical image of the inside of the furnace obtained by the above. The first iTV 36 is connected to the light receiving unit 3 by an image transmission fiber 38 housed in the front i2 measurement lance 12.
2.34 is connected. A second ITV 40 is disposed at the front of the self-propelled cart 18 to monitor the movement of the lowest point of the two rings 14 and 16 near the tip of the measuring lance 12 in a field of view that includes the lowest point. ing. Furthermore, the positions of the laser beam bright spots 26A, 30A on the screen detected by the 11th TV 36 are determined by the 2nd ITV 4.
A mini-computer 42 that calculates the shape of the furnace interior from the true position of the laser beam bright spot obtained by correcting the bending l of the measuring lance 12 detected at 0, the rotation angle θ and the advance/retreat position x of the measuring lance 12. are also provided. As shown in detail in FIGS. 2 and 3, the measurement lance 12 is composed of, in order from the outside, an outer pipe 12B, a first intermediate pipe 12G, a second intermediate pipe 120, and an optical system support pipe 12E. has been done. Said first intermediate vibe 1
2C and the second intermediate pipe 12D, there is a cooling water supply port 1.
Cooling water is supplied from 2F, and the first intermediate pipe 12G
A cooling water drain port 12G is connected between the external pipe 112B and the outside pipe 112B, and cooling water is supplied to both of them for cooling. Furthermore, a purge gas supply port 12H (
Compressed air is supplied from Fig. 1) and air purge is performed. As shown in detail in FIG. 4, the light projecting section 24 directs the laser beam transmitted through the optical transmission fiber 29A to the converter
Optical mirror 2 for projecting toward the furnace wall surface 10B of 0
Contains 4A. On the other hand, as also shown in detail in FIG. 4, the light projecting section 28 takes out the laser beam transmitted through the optical transmission fiber 29B to the outside of the measurement lance 12 and directs it toward the furnace bottom surface 10C, that is, for measurement. Two optical mirrors 28A and 28B for projecting images substantially parallel to the central axis direction of the lance 12, and a motor 28C for two-dimensionally changing the angle of the optical mirror 28B within a plane including the longitudinal direction of the measuring lance 12. It has the function of a beam scanner. The light receiving sections 32, 34 each include a light receiver 32B134B consisting of a lens system for obtaining an optical image. The operation of the embodiment will be explained below. As shown in FIG. 1, the self-propelled cart 18 is advanced and the measuring lance 12 is inserted into the converter 10, which is tilted at right angles after tapping, to its most extreme position. In this state, the laser fires! ! 2
3, the laser beam generated by
The laser beam is projected onto the furnace wall surface 10B and the furnace bottom surface 10C, and the laser beam bright spots 26A and 30A on the wall surface are received by the light receiving sections 32 and 34, respectively. That is, for the measurement of the furnace wall surface 10B, the laser beam generated by the laser oscillator 23 is transmitted to the light projecting section 24 through the optical transmission fiber 29A, and then
As a result, the light is projected onto the furnace wall surface 10B at right angles to the central axis of the measuring lance 12. A light receiving unit 3 whose field of vision includes the bright spot 26A of the laser beam 26
2 obtains an optical image including the laser beam bright spot 26A and transmits it to the 11th TV 36 via the image transmission fiber 38A, where it is imaged. On the other hand, regarding the measurement of the furnace bottom surface 10C, the laser beam generated by the laser oscillator 23 is transmitted to the optical transmission fiber 2.
9B to the light projecting section 28, and the light projecting section 28 projects the light onto the furnace bottom surface 10G while scanning two-dimensionally within a plane including the longitudinal direction of the measuring lance 12. Furnace bottom surface 10
The laser beam bright spot 30A generated at C is detected by the light receiving unit 34, and transmitted to the 117th V36 by the image transmission fiber
It is transmitted and imaged in step 1. The above operations are carried out by the lance drive unit 22 on the measuring lance 12.
By rotating around the axis and moving the self-propelled cart 18 backward in the axial direction, the laser beam 26.30 can scan the entire surface of the converter. Measurements can be taken. In this way, the coordinates of each point in the furnace profile are determined by the positional coordinates of the light emitter 24.28 and the light receiver 32.34, the projection angle of the laser beam 26.3o, the rotation angle of the measuring lance 12, and the optical image. It is completely determined from the position coordinates based on the principle of triangulation. In addition, in order to accurately detect the melting damage position, it is necessary that the central axis of the measuring lance 12 is always constant during a series of measurements. However, when the measuring lance 12 is inserted into the furnace, it is generally deflected by gravity and is also subjected to vertical and horizontal vibrations, so in order to perform accurate measurements, it is necessary to correct measurement errors caused by positional fluctuations of the measuring lance 12. becomes. Therefore, in the present invention, two fixed points on the measuring lance 12,
That is, as shown in FIG.
Laser beam bright spots 26A and 30A detected by TV36
The position of is being corrected. That is, if the central axis of the measuring lance 12 is now displaced from Z to 2' as shown in FIG. 6, the position coordinates U (X, Y, Z) of the laser beam bright spot U are In the 0 coordinate system, it is determined as follows. First, let the lowest point positions of the torus 14.16 be P and Q, respectively, and the position coordinates are P(XalYa, Q), Q(Xb,
Yb, d). Also, the rotation angle of the measuring lance 12 is θ,
If the projection angle of the laser beam is β, and the angle of reception of the laser beam bright spot at the image transmission fiber 38 is α+γ, the position coordinates of the foot T of the perpendicular line drawn from the measurement point U to the Z-axis are (Ktanβ
・xa+(1-Ktanβ)Xb1Ktanβ-Ya+
(1-K tanβ)Yb, (1-K tanβ
) dl. Here, K is expressed by the following formula. K-1/[tanβ+tan(α+γ)]-(1) Furthermore, the following relationship holds true. (1,0,O) ・Q P 'p L cos θ-(2
>(0,1,0)-QPΦL stnθ·(3) Here, L is expressed by the following formula. L-UT = d/ [tanβ+ tan(α+γ)] ・
-(4) Therefore, the following relationship holds true. Z -Z Q -L sln$ -(1-Ktanβ)d -L a-Xb)"+(Ya-Yb)'/d...
...-(5) From the above equations (2), (3), and (5), the true coordinates (X%Y, Z) of the measurement point are finally expressed by the following equation. X-Ktanβ-Xa + (1-Ktanβ>xb
+KOO8θ-d......(6)Y-K
tanβ"Ya+(1-Ktanβ)Yb+Kslnθ
−d −−−−−−−−−(7) Z=(1−
Ktanβ) d −Ka −Xb ) t + (Ya −Yb
) t...-(8) Therefore, the coordinates Xa % Ya 1Xb of the lowest point IP, Q of the ring 14.16 detected by the 21st TV 40. W! detected by the eleventh TV 36 from Yb, d, the rotation angle θ of the measuring lance 12, and the laser beam projection angle β! By correcting the reception angle α+γ of the laser beam bright spot in the i-image transmission fiber 38, the true position coordinates X, Y, and Z of the laser beam bright spot are determined by the above equations (6) to (8). I can do it. According to the inventor's experiments, this embodiment has a measurement point position accuracy of ±1 On and a refractory thickness direction accuracy of ±5 nm. With a data collection time of 5 milliseconds/point (20 seconds/4000 points), it was possible to calculate 4000 points of BuO fill. In this embodiment, since the furnace wall surface 10B and the furnace bottom surface 10G of the converter 10 are simultaneously detected by independent light emitting and receiving systems, the degree of am can be measured quickly. In addition, a single light emitting/receiving system has a furnace wall surface of 10
It is also possible to sequentially detect B and the furnace bottom surface 10C. Furthermore, in this embodiment, a method based on triangulation was used to determine the position of the laser beam bright spot;
Laser radar methods can also be used, such as time measurements with pulsed lasers or phase difference measurements with amplitude modulation. In the above example, the present invention is applied to measuring the brick residual thickness of a converter, but the scope of application of the present invention is not limited to this, and the inner shape of a general melting furnace such as an electric furnace can be similarly measured. It is clear that it can be done.

【Effect of the invention】

As described above, according to the present invention, the local bending amount of the tip of the measuring lance can be detected with high accuracy and corrected appropriately. Therefore, it has the excellent effect that the shape inside the furnace can be measured quickly and with high precision.

[Brief explanation of the drawing]

Fig. 1 shows the overall configuration of an embodiment of a brick residual thickness measuring device for a converter in which the present invention is adopted; 3 is a longitudinal sectional view of the measuring lance, FIG. 4 is a side view of the optical system support vibe, and FIG. 5 is a cross-sectional view of the second industrial television camera. FIG. 6, which is a diagram showing an example, is a diagram showing a method of correcting the detected value at the measurement point according to the bending of the measurement lance in the embodiment. 10... Converter, 12... Measuring lance, 12A, ZlZ"-... Central axis, 14.16... Annular ring, 18... Self-propelled trolley,
19...Encounter position detector, ×...Lance advance/retreat position, 21...Lance drive unit, 22...Rotation angle detector, θ...Lance rotation angle, 24.28.
...Light projection part, -26,30...Laser beam, 26A, 30A...Laser beam bright spot, 32.34.
... Light receiving section, 32A, 34A - Field of view, 36.40 - Industrial television camera (ITV>, 42...
・Mini computer, P, Q...lowest point position.

Claims (1)

[Claims] (1) From the position of the bright spot of the laser beam projected into the furnace,
A furnace shape measurement device that measures the shape of the inside of a furnace in a non-contact manner uses a measuring lance that is inserted into the furnace from the furnace mouth and has multiple rings near its tip and is rotatable around its axis. , a self-propelled cart that supports the rear end of the measuring lance and is movable in the axial direction of the measuring lance; a movement displacement detection means for detecting a displacement of the self-propelled cart; Further, a lance driving means for rotating the measuring lance, a rotation angle detecting means for detecting a rotation angle of the measuring lance, and a light projection disposed on the measuring lance for projecting a laser beam into the furnace at a set angle. means, a light-receiving means disposed on the measurement lance for obtaining an optical image of the interior of the furnace with a field of view including a bright spot of the laser beam from the light projecting means; and a light-receiving means for capturing an optical image obtained by the light-receiving means a second imaging means disposed on the self-propelled cart and configured to image the movement of the lowest point of a plurality of rings near the tip of the measuring lance with a field of view including the lowest point; The true position of the laser beam bright spot obtained by correcting the position of the laser beam bright spot detected by the first imaging means by the amount of bending of the measurement lance detected by the second imaging means; A measuring device for the shape of the furnace interior, comprising: a signal processing means for calculating the shape of the furnace interior from the rotation angle and movement displacement of the lance.