JPH0523870A - Welding monitor - Google Patents

Abstract

PURPOSE:To directly photograph a joined part of a hot forming tube such as a weld tube, a forge-welded tube, etc., by a camera. CONSTITUTION:As for the welding monitor, in a tube manufacturing line 1 of a hot electro-resistance-welded tube or forge-welded tube, etc., a lens unit 2 is provided in the vicinity of a joined part 51 of a hot forming tube 5, the lens unit 2 is protected by a purge and a thermal insulation unit 3, an image obtained by the lens unit 2 is sent to an electronic apparatus 4 such as a two-dimensional image sensor/camera 41, etc., installed on a position separated from a pass line of the line 1, and direct photographing is executed therein.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for monitoring the joining behavior of a joining portion (welding portion or forging portion) of a hot electric resistance welded pipe or a forged pipe for forming and welding a steel strip hot. ..

[0002]

2. Description of the Related Art Conventionally, welding butt points (welding points) of ERW pipes
As means for observing peripheral phenomena, there is JP-A-61-1403.
No. 84, a two-dimensional image sensor / camera is installed above the welding point to observe by this image processing, or an image guide as seen in Japanese Patent Publication No. 60-28590. A method of observing by processing an image through (optical fiber etc.) has been proposed.

The prior art is directed to cold ERW pipes. In this case, the welding point is generally upward due to upward forming, and flash (molten steel) scattered near the welding point
It is easy to install a measuring device such as a camera away from a position where the measuring device such as a camera is not influenced by the electromagnetic induction of the induction heating coil.

On the other hand, in a manufacturing method in which a material is heated to form and weld, such as a hot electric resistance welded pipe or a forged welded pipe, in general, in order to easily discharge hot scale from the inner surface of the pipe, We are doing downward welding. Due to space constraints, it is not possible to secure a sufficient distance between the electronic heating device and the induction heating coil. In the case of a forged tube that does not use an induction heating coil, the material temperature is 1200 to 1300 ° C, which is a high temperature.
It is difficult to take heat protection measures for the camera. As a countermeasure against these problems, conventionally, a camera has been installed at a position away from these high temperature objects by an optical fiber or the like. With the current technology, the number of pixels of the optical fiber is limited to about 30,000 pixels, and there is a problem that the image resolution is poor and it is difficult to obtain a clear image. Further, in the case of an optical fiber, it is difficult to perform focus adjustment and zoom adjustment remotely, and it is necessary to stop the line and perform the adjustment manually.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to allow a camera to directly photograph a joint portion of a hot-formed tube such as a welded tube or a forged tube.

[0006]

A welding monitoring apparatus of the present invention comprises a lens unit provided in the vicinity of a joint of a hot formed pipe in a pipe making line such as a hot electric resistance welded pipe or a forged welded pipe.
The lens unit is protected by a purging and heat-insulating unit, and the image obtained by the lens unit is sent to an electronic device such as a two-dimensional image sensor / camera installed at a position apart from the path line of the line, and direct photographing is performed there. The above-mentioned problems are solved by the means characterized by carrying out.

[0007]

The feature of the apparatus of the present invention is that in a hot pipe-making line such as an electric resistance welded pipe or a forged pipe, the joint is not an indirect means such as an optical fiber but an electronic device such as a two-dimensional image sensor or camera. The point is that it was possible to obtain a clear image with high resolution by shooting directly with the device.

If there is a sufficient space above or below the joint, it is possible to install a camera using a telephoto lens or the like at a distance. However, in a general pipe manufacturing line, there is interference from a mill roll stand or the like, and the space above or below the joint is very narrow. In particular, in a hot pipe manufacturing line, high-temperature radiant heat is emitted from the material, and it is not preferable to place an electronic device in this narrow space in terms of maintainability and durability.

Therefore, in the present invention, as a means for directly imaging the joint portion with a camera or the like, a periscope type lens using a means such as a mirror or a prism capable of changing the optical axis is used to connect the camera or the joint portion. It can be installed at a position away from.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the welding monitoring apparatus of the present invention will be described with reference to the drawings.

As shown in FIGS. 1 and 2, the welding monitoring apparatus of the present invention is installed in a pipe making line 1 such as a hot electric resistance welded pipe or a forged pipe, and its main constituent elements are a lens unit. 2, a purge and heat shield unit 3, and an electronic device 4 such as a two-dimensional image sensor 41.

This welding monitoring apparatus is provided with the lens unit 2 near the joint 51 of the hot forming pipe 5,
Is protected by a purging and heat-insulating unit 3, and the image obtained by the lens unit 2 is sent to an electronic device 4 such as a two-dimensional image sensor / camera 41 installed at a position apart from the path line of the line 1, and the direct photographing is performed there. To do.

An embodiment in which the welding monitor of the present invention is applied to an electric resistance welding line for hot downward forming (the welding point is on the lower surface) will be described in detail.

The two-dimensional image sensor / camera 41 is installed on a pedestal (not shown) immediately below the joining portion 51 of the molding pipe 5, and is movable in the molding pipe flow direction A and the direction B perpendicular to the flow direction A. Therefore, an arbitrary position near the joint 51 can be photographed.

A mirror 21, a lens group 22 corresponding to the unit length, and a prism 23 are incorporated in the lens unit 2, and an image of the joint 51 is guided to a camera 41 out of line. In the case of the illustrated example, the camera 41 is installed above the lens unit 2 from the viewpoint of workability, but it is located laterally (right side in the drawing).
May be attached to. In this case, the prism 23 becomes unnecessary. Further, a mirror can be used instead of the prism 23. The length of the unit 2 is determined by measuring a range where the camera 41 is not subjected to electromagnetic induction by the induction heating coil 6. The image of the camera 41 can be monitored by the monitor TV 42. Focus adjustment and zoom adjustment of an image are performed by moving the position of the lens group 22 and the servo motor 25 by the remote control panel 24. As a result, the worker can perform remote control from the operator's cab (not shown) without approaching the scale or the line where water is released.

The light quantity of the image is adjusted according to the type of the optical filter 26, and the appropriate filter 26 is selected depending on whether visual inspection or image processing by a computer is performed.

The lens unit 2 is housed in a waterproof / dustproof stainless cover 27, and a heat-resistant glass 28 is attached to the field of view.

The purging and heat insulating unit 3 uses an air purging hood 31 to move air upward so that the roll cooling water, the hot scale, and the molten steel at the welded portion do not drop on the heat-resistant glass 28 and obstruct the visual field. While blowing out
An air purge nozzle 32 for horizontally purging the surface of the glass 28 is attached. Furthermore, dirt, large scale, etc. on the surface of the glass 28 that cannot be removed by the air purge,
It is removed by a mechanical wiper 34 attached to a sliding glass protection shutter 33. The material of the mechanical wiper 34 is preferably soft rubber, urethane, sponge, or the like that applies a uniform surface pressure to the glass surface.

The protective shutter 33 is slid to the right in the figure during normal observation, but if there is a risk of a large amount of molten steel dropping due to overheating of the joint due to an emergency stop of the line, etc., slide it to the left in the drawing. , Heat-resistant glass 28
To prevent the glass 28 from being broken by molten steel.
The shutter 33 is an air cylinder or the like (not shown)
It can be operated remotely from the cab.

Specific examples of the present invention will be described below.

(1) Pipe making conditions: Molded pipe outer diameter 90 to 140 mm Welding part temperature 1350 to 1400 ° C. Base material temperature 850 to 900 ° C. Pipe making speed 80 to 100 m / min (2) Lens unit specification: Field of view diameter 16 ~ 65m
m (zoom ratio 1 to 4) Focus adjustment range 60 mm (3) Camera specifications: 1/2 inch image sensor camera (4) Monitoring results: Under the above conditions, the welding point behavior could be clearly understood. ..

With this device, roll cooling water, hot scale, steam, etc. scatter and fall, and electronic equipment such as an image sensor and camera is installed in a hot pipe manufacturing line with high temperature radiant heat, and further for welding. It became possible to obtain a clear image of the joint without receiving induction noise from the high frequency induction heating coil.

In the above description, the case of hot downward pipe making is described, but the present invention is also applicable to hot upward pipe making or cold upward pipe making.

[0024]

According to the present invention, the behavior in the vicinity of the welding point, which has conventionally been observed by an indirect means such as an optical fiber due to space restrictions and a bad environment, can be directly photographed by a camera. Therefore, the amount of information obtained can be dramatically increased, and the working accuracy and efficiency of the pipe manufacturing line can be improved.

[Brief description of drawings]

FIG. 1 is a side view of a welding monitoring device of the present invention.

FIG. 2 is an end view taken along the line II-II of FIG.

[Explanation of symbols]

 1: Pipe making line 2: Lens unit 3: Purge and heat insulating unit 4: Electronic equipment 5: Molded pipe 6: High frequency induction heating coil

Claims (1)

Claim: What is claimed is: 1. In a pipe manufacturing line such as a hot electric resistance welded pipe or a forged welded pipe, a lens unit is provided in the vicinity of a joint of the hot formed pipe, and the lens unit is provided by a purging and heat insulating unit. Protect and send the image obtained by the lens unit to an electronic device such as a two-dimensional image sensor or camera installed at a position apart from the path line of the line,
Therefore, the welding monitoring device is characterized by taking images directly.