JP6624042B2 - Apparatus and method for remote inspection of narrow part in vertical furnace - Google Patents

Description

  The present invention relates to an apparatus and a method for remotely inspecting a narrow part in a vertical furnace.

  FIG. 1 is a diagram showing an example of equipment arrangement in a continuous annealing line for steel sheets. A vertical annealing furnace, which is one of the vertical furnaces, is provided in the line. The cold-rolled steel sheet paid out from the pay-off reel 1 is welded to a preceding material by a welder 2, sent to a vertical annealing furnace 4 via a looper 3, annealed, and then passed through a looper 3 to a tension reel 5. It is wound up.

  Inside the vertical annealing furnace 4, a plurality of radiant tubes (hereinafter, also abbreviated as RT) for heating a steel sheet are arranged. Since a high-temperature gas flows through the inside of the RT, it is necessary to periodically check the pipe itself for bending or cracking. Generally, a vertical annealing furnace has a height of several tens of meters, and the inspection work is performed at a high place, requiring a great deal of time and cost including preparation, inspection, and clearing.

  FIG. 2 is a diagram showing a situation where a worker directly enters the furnace and performs an inspection work. This shows a state of inspection work by a conventional worker, in which a worker 6b with a lifeline 8 becomes an inspector, and a damaged state of the radiant tube 7 between the furnace top 4a and the hearth 4b of the vertical annealing furnace 4. Inspect visually. During the inspection work, the worker 6a at the furnace top 4a and the worker 6c at the hearth 4b apply tension to the lifeline 8 so that the position of the worker 6b to be inspected does not fluctuate.

  Since the inside of the furnace is in a poor environment and the load on workers is large, inspection methods have been proposed as work improvement measures, such as checking with a hoisting device such as a gondola, and putting a camera in the furnace and raising and lowering with a hoisting device. However, inspection of the narrow part between the radiant tubes in the furnace had room for improvement in safety and efficiency.

  To cope with this, there is a technique disclosed in Patent Document 1. In this technology, an omnidirectional camera is equipped with an elevating device to check the radiant tube of the vertical annealing furnace so that the radiant tube can be raised and lowered between the radiant tubes and the inspection can be performed remotely while looking at the screen. Further, in a dark furnace, since it is not possible to take a picture as it is, an omnidirectional camera is provided with a light so that a picture can be taken.

JP 2013-40714 A

  However, the technique disclosed in Patent Document 1 has the following problems.

(1) Adjusting the position of the omnidirectional camera Although the introduction of the omnidirectional camera enabled the safety of inspection of the narrow part inside the furnace, the omnidirectional camera was moved up and down while checking slowly so as not to overlook the part to be inspected. There is a need.

  Further, in order to compare the past inspection record with the image by looking at the image, the omnidirectional camera must be moved up and down while visually adjusting the inspection position to the same position every time.

  For the above-mentioned reason, when the inspector climbs up the inside of the furnace to perform the inspection, the work that can be performed in a few hours takes about two to three times as much as six to eight hours.

(2) Necessity of vertical furnace modification The vertical annealing furnace targeted in Patent Literature 1 has a top roll at the top of the furnace, and a radiant tube is arranged directly below the top roll in the height direction of the furnace. . Normally, the top of the top roll has a structure in which the furnace lid can be removed so that the roll can be replaced. However, there is no furnace lid structure above the position where the omnidirectional camera can be raised and lowered to check the radiant tube from the side, and a new opening is installed at the furnace top to escape the top roll when the omnidirectional camera is raised and lowered It needs to be remodeled.

  The present invention has been made in view of such a conventional problem, and it is possible to safely and efficiently inspect a narrow portion in a vertical furnace without performing a new significant vertical furnace modification. It is an object of the present invention to provide an apparatus and a method for remotely inspecting a narrow part in a vertical furnace.

  The above problem can be solved by the following invention.

[1] A remote inspection device for a vertical furnace narrow section for remotely inspecting a vertical furnace narrow section,
An omnidirectional camera and an imaging device including an antenna and a lighting device for transmitting an image obtained by capturing an image of the vertical furnace narrow portion with the omnidirectional camera,
A winch wire for raising and lowering the imaging device, a winch for lowering,
And an image processing device that corrects image distortion of the transmitted image,
The winch includes a rotation control device that controls a rotation speed and a stop position of the rotation drive device,
When sending the winch wire into the vertical furnace,
Remote inspection of a vertical furnace characterized by being configured to avoid a structure disposed immediately below the furnace top opening through a support column and a guide support arranged near the furnace top opening of the vertical furnace. apparatus.

[2] The remote inspection device for a narrow part in a vertical furnace according to the above [1],
The vertical furnace is a vertical annealing furnace,
The imaging device has a lifting function along a passing chain, and includes a passing chain passing shackle for inserting the passing chain,
The said structure is comprised so that it may be a top roll, The remote inspection apparatus of the vertical furnace characterized by the above-mentioned.

[3] A method for remotely inspecting a narrow part in a vertical furnace, which remotely inspects a narrow part in a vertical furnace,
A winch wire is fed into the furnace via a support installed around the opening of the furnace top and a structure disposed directly below the opening via a guide support fixed to the support, Feeding step into the furnace;
An omnidirectional camera and an imaging device equipped with an antenna and an illuminating device that transmits an image obtained by photographing a narrow portion of the vertical furnace inside the omnidirectional camera are fixed to a winch wire, a fixing step of the winch wire and the imaging device,
Controlling the raising or lowering of the winch, moving the imaging device to a predetermined furnace height position and stopping, and then performing in-furnace shooting with an omnidirectional camera of the imaging device; When,
The captured image is transmitted to the image processing apparatus, image distortion correction is performed, cracking in the narrow portion of the vertical furnace, determination of the presence or absence of bending, image processing and inspection determination step,
A method for remotely inspecting a narrow part in a vertical furnace, comprising:

[4] In the remote inspection method for a narrow part in a vertical furnace according to the above [3],
The vertical furnace is a vertical annealing furnace,
The structure is a top roll,
Pulling the steel plate from the furnace by attaching the threading chain to the tip or tail end of the steel sheet, after performing the steel sheet removing step from the furnace by the threading chain, perform the step of feeding the winch wire into the furnace,
A method of remotely inspecting a vertical furnace, comprising fixing the winch wire and an image pickup device, and moving the image pickup device up and down along a plate chain.

  According to the present invention, a winch wire is fed into the furnace so as to avoid a structure by providing a column and a guide support near the opening of the furnace top, and the imaging device is moved up and down. It is now possible to safely and efficiently inspect the narrow part inside the vertical furnace without remodeling the furnace.

It is a figure showing the example of equipment arrangement in the continuous annealing line of a steel plate. It is a figure which shows a mode that an operator enters a furnace directly and performs an inspection work. It is a figure which shows the example of a whole structure of the remote inspection apparatus of the narrow part in a vertical annealing furnace. It is a figure which shows the structural example of a support | pillar and a guide support. FIG. 2 is a diagram illustrating a configuration example of an imaging device used in the present invention. FIG. 3 is a diagram illustrating an example of a captured image and an image after correction. It is a figure which shows the example of a processing procedure in the remote inspection method of the narrow part inside a vertical annealing furnace of a continuous annealing line of a steel plate.

  Hereinafter, an embodiment of the present invention will be described with an example of inspection of a radiant tube in a vertical annealing furnace of a continuous annealing line for steel sheets. It is needless to say that the present invention can be applied not only to the vertical annealing furnace but also to other vertical furnaces. In addition, as a vertical furnace, not only a large vertical furnace as shown in FIG. 1 and FIG. 2 but also a small vertical furnace as long as an imaging device can photograph a narrow part which is difficult to inspect in the furnace. It is possible.

  FIG. 3 is a diagram showing an example of the overall configuration of a remote inspection device for a narrow portion in a vertical annealing furnace. In the drawing, 4 is a vertical annealing furnace, 4a is a furnace top, 4b is a hearth, 7 is a radiant tube, 11 is a winch, 12 is a winch wire, 13 is a support, 14 is a guide support, 15 is a top roll, 16 is A threading chain, 17 is a bottom roll, 18 is an imaging device, 19 is a shackle for threading a threading chain, and 20 is an image processing device.

  2 shows a state in which a plurality of radiant tubes 7 arranged in the height direction immediately below a top roll 15 installed inside a vertical annealing furnace 4 are photographed by an imaging device 18. Here, an example of the radiant tubes arranged below the top roll immediately below the furnace top opening as the narrow portion inside the furnace that needs to be inspected is shown. However, the present invention is not limited to this example. In the vertical furnace described above, the present invention is also applicable to inspection of a narrow portion below a structure disposed immediately below a furnace top opening.

  Then, the image captured by the imaging device 18 is wirelessly transmitted to the image processing device 20 installed at a remote place, and the image is subjected to image processing. The presence or absence of bending or cracking of the tube itself is determined from the image processed image.

  The imaging device 18 moves up and down inside the vertical annealing furnace 4 with the winch wire 12 sent out from the winch 11.

  The winch 11 has a rotation drive device (not shown) and a rotation control device that controls the rotation speed and the stop position of the rotation drive device. The winch wire 12 is wound and wound at a desired rotation speed and a stop position. You can control the lowering. Thereby, the imaging device can be automatically moved or stopped at a predetermined height position.

  In the vertical annealing furnace of the continuous annealing line for steel sheets, when the furnace is lowered or started up, the steel sheet is pulled out of the vertical annealing furnace or charged with a threading chain 16 attached to the leading end or tail end of the steel sheet. In the present invention, the threading chain 16 remaining in the furnace after the steel sheet is extracted is used.

  If the imaging device 18 is moved up and down along the passing chain 16, it is possible to reduce the lateral swing of the imaging device, which is more preferable. For this reason, the imaging device 18 includes a shackle 19 for passing a threading chain through which the threading chain 16 is inserted (see FIG. 5 and a description about FIG. 5 described later).

  FIG. 4 is a diagram illustrating an example of the structure of the support and the guide support. In the figure, 13 denotes a support, and 14 denotes a guide support. As shown in FIG. 3, the column 13 is installed on the furnace top 4 a to change the direction of the winch wire 12 and support the guide support 14.

  The support column 13 is provided with a guide wheel (sheave) for changing the direction of the winch wire at the tip as shown in FIG. 4, and has a furnace top opening so as to support the guide support 14 so that the guide support 14 is arranged at the furnace top opening. It is located near.

  Then, the guide support 14 moves the winch wire from the furnace (a top roll in the case of the vertical annealing furnace shown in FIG. 3) by obstructing an obstacle (a top roll in the case of the vertical annealing furnace in FIG. 3) immediately below the furnace top opening provided directly above the top roll. It has a U-shaped bent shape to be fed into. For this reason, when creating the guide support, the position and diameter of the furnace top opening, the distance between the structure (in FIG. 3, the top roll) that is an obstacle immediately below and the furnace top, and the structure that is an obstacle immediately below (the top roll). In the case of FIG. 3, the optimum shape should be appropriately determined according to the actual application target such as the size of the top roll).

  In addition, by inverting the bent portion of the guide support, it is possible to easily inspect adjacent inspection objects (radiant tubes in FIG. 3) at the same height position of the furnace.

  FIG. 5 is a diagram illustrating a configuration example of an imaging device used in the present invention. FIG. 5A is a schematic diagram showing the configuration, and FIG. 5B is a photograph in the furnace. In the figure, 12 is a winch wire, 16 is a threading chain, 18 is an imaging device, 19 is a shackle for threading the threading chain, 21 is an omnidirectional camera, 22 is an LED light, 23 is a battery, and 24 is an access point antenna. Represent.

  The imaging device 18 suspended from the winch wire 12 includes an omnidirectional camera 21 equipped with a fish-eye lens (not shown), an LED light 22 as a lighting device for a narrow part in the furnace, a battery 23 for each device, and a captured image. An access point antenna 24 that transmits the image data to an image processing apparatus that performs image processing is built in the gantry.

  In addition, in the vertical annealing furnace of the continuous annealing line for steel sheets, in order to use the threading chain 16 as described above, on both sides of the mount of the imaging device 18, the threading chain 16 for inserting the threading chain 16 is inserted. The shackle 19 is installed, and the imaging device 18 is moved up and down along the passing chain 16. This makes it possible to more stably take an image without blur due to twisting or the like.

  FIG. 6 is a diagram illustrating an example of a captured image and an image after correction. FIG. 6A is an image before correction obtained by wide-angle photographing the front and rear radiant tubes (RT) with an omnidirectional camera from the top of the furnace, and FIG. 6B is an RT support unit and RT in order from the top. 9 shows an image after performing image distortion correction for the full width and the rear surface RT.

  An image photographed by the imaging device 18 shown in FIG. 3 is wirelessly transmitted to an antenna (not shown) of the image processing device 20, and the image processing program incorporated in the image processing device 20 removes image distortion from the center coordinates and curvature of the lens. Correction has been performed. A portable personal computer may be used as the image processing device used at the work site.

  Also, if the images before and after the correction for the same inspection point are stored in the recording device, by comparing the previously recorded image with the newly obtained image, the degree of the defect of the radiant tube can be more accurately and accurately determined. The determination can be made reliably, and the degree of deterioration in the future can be predicted. In addition, although the inspection about the radiant tube is mainly described, it is not limited to this.

  Devices from photographing to image processing are commercially available as systems and can be used. In the present invention, similarly to Patent Document 1, an image processing system product name: CamLight (LOARANT) [the optical system is a product name: ARTCAM300ML (ARTRAY) as an omnidirectional camera, and a product name: FJ062K (Opto Art) as a lens] It is used as a part of the image processing device 20 and the imaging device 18.

  Inspection processing of the narrow portion inside the vertical annealing furnace of the continuous annealing line for steel sheets to which the present invention is applied is performed through the following steps using the above-described remote inspection device. FIG. 7 is a diagram illustrating an example of a processing procedure in a remote inspection method of a narrow portion in a vertical annealing furnace of a continuous annealing line of a steel sheet. Explanation will be made based on FIG.

Step01: (Remove steel plate from furnace by threading chain)
After the supply of high-temperature gas to the radiant tube inside the vertical furnace is stopped and the temperature in the furnace is cooled to the atmospheric temperature, a threading chain is attached to the tip or tail end of the steel sheet and the steel sheet is pulled out of the furnace.

Step02: (Extending the winch wire into the furnace)
The winch wire is sent into the furnace, avoiding the top roll, via a support installed around the opening at the furnace top and a guide support fixed to this support, and guided to the outside of the furnace through the opening in the hearth. .

Step03: (Fixing winch wire and imager)
Fix the imaging device to the winch wire outside the furnace, lift the imaging device to the inside of the furnace, insert the passing chain through the shackle for passing the passing chain of the imaging device, and move the imaging device along the passing chain. To raise and lower.

Step04: (Photo taken inside the furnace using the imaging device)
After controlling the raising or lowering of the winch and moving the imaging device to a predetermined furnace height position and stopping the imaging device, the omnidirectional camera of the imaging device performs imaging in the annealing furnace. At this time, the height position of the RT to be inspected is often known from the design drawing or the inspection history. Therefore, if the winch hoisting or lowering position is stored and the drive of the winch is controlled so as to automatically move / stop the imaging device to the stored position, it is possible to quickly and accurately capture the image using the imaging device. is there.

Step05: (Image processing and inspection judgment)
The photographed image is transmitted to the image processing apparatus, the image is corrected for distortion, and the presence or absence of distortion such as cracking or bending of the radiant tube is determined. The necessity of component replacement or the like is determined.

  The remote inspection procedure for the narrow part inside the vertical annealing furnace in the continuous annealing line for steel sheets has been described above. However, in other vertical furnaces, for example, Step 01: (steel sheet removal from the furnace using a threading chain) is unnecessary or necessary. When there is an impossible procedure, it may be appropriately omitted, and when there is a necessary procedure, it may be added as appropriate.

  When the present invention is applied to the vertical annealing furnace shown in FIG. 1 at the timing of repair performed once every six months, the processing time can be reduced to about 2/3 compared to the processing time in Patent Document 1. It was possible to perform safe, accurate and detailed inspections without any human work in the furnace. In a vertical annealing furnace that requires continuous operation, inspection at the time of repair is important, and the above effects are very valuable in actual operation.

Reference Signs List 1 payoff reel 2 welder 3 looper 4 vertical annealing furnace 4a furnace top 4b hearth 5 tension reel 6a-6c worker 7 radiant tube 8 lifeline 11 winch 12 winch wire 13 support 14 guide support 15 top roll 16 threading chain 17 bottom Roll 18 Imaging device 19 Shackle for threading through chain 20 Image processing device 21 Omnidirectional camera 22 LED light 23 Battery 24 Access point antenna

Claims (4)

A remote inspection device for a vertical furnace narrow section for remotely inspecting a vertical furnace narrow section,
An omnidirectional camera and an imaging device including an antenna and a lighting device for transmitting an image obtained by capturing an image of the vertical furnace narrow portion with the omnidirectional camera,
A winch wire for raising and lowering the imaging device, a winch for lowering,
And an image processing device that corrects image distortion of the transmitted image,
The winch includes a rotation control device that controls a rotation speed and a stop position of the rotation drive device,
When sending the winch wire into the vertical furnace,
A vertical type, wherein the guide support is configured so as to avoid a structure disposed immediately below the furnace top opening through a column, a guide support arranged near a furnace top opening of a vertical furnace. Furnace remote inspection device. The remote inspection device for a narrow part in a vertical furnace according to claim 1,
The vertical furnace is a vertical annealing furnace,
The imaging device has a lifting function along a passing chain, and includes a passing chain passing shackle for inserting the passing chain,
The said structure is comprised so that it may be a top roll, The remote inspection apparatus of the vertical furnace characterized by the above-mentioned. A method for remotely inspecting a vertical furnace narrow portion, wherein the vertical furnace narrow portion is remotely inspected,
The winch wire is sent into the furnace from the opening via the support provided around the opening at the furnace top and the guide support fixed to the support, avoiding the structure disposed immediately below the opening. Feeding the winch wire into the furnace,
An omnidirectional camera and an imaging device equipped with an antenna and an illuminating device that transmits an image obtained by photographing a narrow portion of the vertical furnace inside the omnidirectional camera are fixed to a winch wire.
Controlling the raising or lowering of the winch, moving the imaging device to a predetermined furnace height position and stopping, and then performing in-furnace shooting with an omnidirectional camera of the imaging device; When,
The captured image is transmitted to the image processing apparatus, image distortion correction is performed, cracking in the narrow portion of the vertical furnace, determination of the presence or absence of bending, image processing and inspection determination step,
A method for remotely inspecting a narrow part in a vertical furnace, comprising: The method for remotely inspecting a narrow part in a vertical furnace according to claim 3,
The vertical furnace is a vertical annealing furnace,
The structure is a top roll,
Pull the steel plate out of the furnace by attaching the threading chain to the tip or tail end of the steel sheet, after performing the steel sheet removing step from the furnace by the threading chain, perform the feeding step of the winch wire into the furnace,
A method of remotely inspecting a vertical furnace, comprising fixing the winch wire and an image pickup device, and moving the image pickup device up and down along a plate chain.