JPH0623741B2 - Automatic non-destructive inspection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention runs along a side wall or a bottom wall of a pressure vessel, a storage tank, or the like, and the presence or absence of scratches or the thickness of the constituent material of the wall. The present invention relates to an automatic non-destructive inspection device for automatically detecting or measuring.

[Prior Art] In pressure vessels and the like, it is necessary to take measures as early as possible by detecting the decrease in thickness and the occurrence of internal scratches due to use. As such a non-destructive inspection method, an ultrasonic flaw detector that detects the thickness or presence of scratches by transmitting ultrasonic waves from the front to the inside of the material to be measured and receiving the echo from scratches on the rear surface or inside Eddy current flaw detectors are used. In such a nondestructive flaw detector, it is necessary to place a sensor such as an ultrasonic probe in close contact with the material to be measured as much as possible, and conventionally, this has been done manually.

[Problems to be Solved by the Invention] However, it is dangerous to move a probe along a vertical wall or a bottom wall of a pressure vessel or the like while working at a high place or because the scaffolding is bad. This is a time-consuming work, is inefficient, and may be performed under such adverse conditions, so that the measurement accuracy is not good. In particular, there is a case where the work is performed in an environment harmful to the human body such as a pressure vessel used in a nuclear power plant, and it has been desired to develop an unmanned device. Therefore, a method is conceivable in which the probe is conveyed while being pressed by a towing device that travels along these wall surfaces. Such a traction device is usually composed of a suction mechanism that sucks the device on a wall surface and a traveling mechanism that moves along the wall surface. The suction mechanism uses a magnetic force or uses a vacuum. and so on. However, even if the flaw detector is placed directly on such a traction device, the adhesion between the flaw detector and the surface to be measured becomes insufficient due to unevenness and curvature of the surface to be measured, and good measurement values cannot be obtained. There was a problem.

[Means for Solving the Problems] In order to solve the above problems, the present invention relates to a frame fixed to a traction device that travels while adsorbing to a wall surface, and a pivotally rotatable frame. A mounted arm, a carriage pivotally attached to a free end of the arm, and a probe mounted on the carriage and rolling or sliding along a wall surface as the carriage travels; An elastic member for pressing the dolly against the wall surface is provided between the dolly or the arm, and a stopper for restricting a rotation angle of the arm within a predetermined range is provided.

[Operation] In such an automatic non-destructive inspection device, since the carriage is pressed by the elastic member, even if the wall surface is inclined or gravity acts in reverse, such as under the bottom surface, For example, the wheel-shaped ultrasonic probe always comes into contact with the wall surface and follows the unevenness of the wall surface. By restricting the expansion and contraction width of the elastic member by restricting the rotation angle of the arm within a predetermined range by an appropriate stopper,
The reaction force applied from the dolly to the frame, that is, the traction device is suppressed within a certain range, and this reaction force is prevented from exceeding the suction capacity of the traction device and separating the traction device from the wall surface.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 to 5.

In these drawings, reference numeral 1 is a traction device, and a covering body 4 in which an annular side wall 2 and a top plate 3 are integrally formed, and the inside of the covering body 4 is exhausted to adsorb the covering body 4 on a wall surface. Supported by a vacuum generator 5 and a bearing 6 projecting from the lower surface of the top plate 3, driven by a motor (not shown) of the vacuum generator 5 to rotate while abutting against a wall surface, and the covering 4 Is provided with a drive wheel 7 for moving along the wall surface, and it is possible to adsorb and run even if the wall surface has a certain degree of flatness, regardless of the inclination. The side wall 2
An annular seal member 8 made of an elastic material such as rubber and configured to seal the gap between the side wall 2 and the wall surface is disposed on the inner side of the wall by being pressed against the wall surface by a coil spring 9.
It should be noted that in the towing device 1, if the suction is too strong, traveling becomes difficult, and if the suction is weak, the load cannot be withstood and the device falls or slips. Therefore, the detection for detecting the atmospheric pressure inside the cover 4 is performed. A device (not shown) is provided, a set value corresponding to the load is set in advance, and a control device (not shown) in the operation panel 10 controls so that the detected value matches the set value. In addition to this, the traction device 1 is also provided with a detector that detects a traveling distance, a speed, an inclination angle, and the like. The height of the cover 4 (distance between the top plate and the wall surface) is constant when the wall surface is flat (determined by the mounting position of the drive wheel 7).

Next, the automatic nondestructive inspection device according to the present invention will be described. Reference numeral 21 in the drawing denotes a frame which is fixed to the rear side surface of the traction device 1 by a bolt (not shown) and has a substantially U shape in a plan view. The frame 21 includes a pair of side plates 23.
Are connected by a connecting member 24 and a top plate 25, bolt holes 26 through which the above bolts are inserted are formed at both ends of the connecting member 24, and a pair of pivots projecting to both sides are formed on the front side of the side plate 23. 27 are provided, and support arms 29 are pivotally attached to the pivot shafts 27 via bearings 28, respectively. The free ends of these support arms 29 are attached to the carriage 3
0 is pivotally mounted via a bearing 32 to a pivot 31 that is provided on both sides of the center of the 0.

The carriage 30 has a structure in which a pair of side plates 33 are connected by a top plate 34 and connecting members 35, 36, 37, and one front wheel (wheel on the frame 21 side) 39 and a pair of left and right rear wheels 40,
40 is provided, and in the main body portion 41 on the front side of the carriage 30,
An ultrasonic probe 42 is attached. The ultrasonic probe 42 includes an elastic body 44 around a drum-shaped probe body 43.
The shaft of the probe 42 is rotatably supported by a bearing 45 provided inside the side plate 33 of the carriage 30, and a liquid is sealed inside the elastic body 44. .
The liquid transmits ultrasonic waves and is appropriately applied with pressure, and elastically deforms during rolling to maintain a constant distance between the wall surface and the axis of the probe 42. There is. The probe 42 abuts on the surface to be measured and rolls along with the traveling of the carriage 30 to emit and receive ultrasonic waves, and sends this data to the control unit 47 via the collective cable 46.
Calculate the thickness of the material to be measured and the presence / absence of scratches, and use the result on CRT4
8 or the Ben recorder 49, and is recorded on the video recorder 50. Immediately in front of the probe 42, a fountain nozzle 52 attached to a mounting member 51 provided so as to hang down from the top plate 35 of the carriage 30.
Is provided so as to face the surface to be measured, and a hose 54 connected to a water supply device 53 is connected to the nozzle 52, and water, which is a medium for transmitting ultrasonic waves, is provided between the surface to be measured and the probe 42. Is designed to be emitted.

Mounting members 61 each having a L-shaped cross section are bent and fixed to both side surfaces of the rear end of the frame 21. On the other hand, at the center of the support arm 29, mounting members having substantially the same shape are mounted. 62 is mounted upside down from the mounting member on the frame 21 side. A coil spring 63 is stretched between the bent portions 61a and 62a of these mounting members.
a and 62a are urged toward each other so that the frame 2
The trolley 30 is pressed downward with respect to 1. The front wheel 39 is attached to the lower surface of the protruding portion 64a of the mounting member 64 having an L-shaped cross section, which is fixedly installed on the front side of the carriage 30, and the pin 6 is provided on the upper surface of the protruding portion 64a.
5, a coil spring 66 is arranged around the pin 65 between the upper surface of the protruding portion 64a and the lower surface of the frame 21 so as to bias them in a direction of separating them. Further, a through hole 67 through which the support arm 29 is inserted is provided at a position slightly forward of the pivot 31 of the side plate 33 of the carriage 30.
A stopper 68 formed with is formed so as to project, and this through hole 67 is formed with a vertical play with respect to the support arm 29, and regulates the vertical movement of the support arm 29 beyond this play. .

The towing device 1 is provided with an illuminating device 71 for illuminating the traveling direction of the towing device 1 and an ITV (industrial television) camera 72 for photographing the illuminated portion, and the frame 21 is provided on the frame 21. An illumination device 73 and an ITV camera 74, which similarly illuminate and photograph a deep wound portion, are provided, and these images are visualized on a monitor 75. The drive control signal cable of the above-described towing device 1 and the ITV camera 7
A cable for transmitting signals of 2,74 images or a signal for handling signals of the cameras 72, 74 and a hose 54 for sending water as a measuring medium of the probe 42 are bundled together to form a collective cable 46. The traction device 1 is dragged to move.

Next, the operation of the ultrasonic flaw detector constructed as described above will be described. Prior to operation, the weights of the ultrasonic probe 42, the carriage 30, the frame 21, and the like, which are loads, and the maximum value of the reaction force applied to the traction device 1 from the elastic members (coil springs) are calculated, and shown in the figure. As described above, the control atmospheric pressure value in the cover 4 is set in the control device in the operation panel 10 so as not to drop even when traveling on the bottom plate lower surface. The operation of the towing device 1 is performed by visually observing a place directly visible to a human, and, for example, in the case where a person cannot enter such as a pressure vessel for nuclear power generation, an image of an ITV camera 76 installed in advance at an appropriate place, Alternatively, the image of the ITV camera 72 attached to the towing device 1 is displayed on the monitor 7
Judgment is made according to 5, 77.

When the towing device 1 travels along the wall surface W, the frame 21
A support arm 29 pivotally attached to the tow pulls the carriage 30. At this time, the coil spring 66 on the front side presses the mounting member 64 downward against the frame 21, and the support arm 29
The coil spring 63 stretched between the mounting member 62 mounted on the frame 21 and the mounting member 61 fixed to the frame 21 presses the support arm 29 against the wall surface W, and the support arm 29 is connected via the pivot 31. Since it pushes the trolley 30,
The dolly 30 is pressed from the frame 21 at three front and rear points. When the wall surface is straight along the traveling direction, the front wheel 39, the probe main body 44, and the rear wheel 40 are all in contact with the wall surface as shown in FIG. On the other hand, when traveling on a convex surface such as the outer surface of the boundary between the side wall and the bottom plate of the container, the carriage 30
Rotates about a pivot 31 to change its posture. At this time,
Depending on the position of the center of curvature of the convex surface, the rear wheel 40 and the probe 4
2. The front wheel 39 is always in contact with the wall surface. On the other hand, when traveling on a concave surface such as the inner surface of the container, the front wheel 39 and the rear wheel 40 are always in contact with the wall surface.
May be separated from the wall surface, but as long as its curvature does not exceed a certain limit, the probe 42 is elastically deformed to keep contact with the wall surface. In such a curved traveling, in any case, the trolley 30 rotates about the pivot 31, the inclination angle of the support arm 29 changes, and when the angle change becomes a certain value or more, the support arm 29 stops.
Since it abuts the through hole 67 of No. 8, further change is prevented. This prevents the elastic members 63, 66 from being excessively deformed and exerting a reaction force exceeding the suction force of the traction device 1 itself. In particular, in the case of traveling on a concave surface, the pulling device 1 itself easily causes a seal leak between the cover 4 and the wall surface, and the posture change of the trolley 30 also acts in the direction of increasing the reaction force, so that the play of the through hole 67 is also prevented. It has been made smaller in that direction.

Note that the implementation of the present invention is not limited to the above example, and the type and structure of the probe may be appropriately changed, for example.

[Effects of the Invention] As described in detail above, the present invention relates to a frame fixed to a traction device that travels while adsorbing to a wall surface, an arm pivotally attached to the frame, and a freedom of the arm. A bogie pivotally attached to the end and a probe mounted on the bogie and rolling or sliding along a wall surface as the bogie runs are provided, and the bogie is provided between the frame and the bogie or arm. Since the elastic member that presses against the wall surface is provided, the probe can be brought into close contact with the wall surface regardless of the inclination of the wall surface, and the probe can be smoothly moved to perform good automatic measurement. Therefore, in the past
It has an excellent effect that the measurement work can be performed efficiently and with high accuracy in a place where the scaffolding is bad, and the measurement work can be performed unmanned even in an environment bad for human health such as a container for nuclear power generation. In addition, since the rotation angle of the arm is regulated within a predetermined range by the stopper, the elastic member is not excessively deformed and a large reaction force is not applied to the traction device. It is prevented from leaving the wall.

[Brief description of drawings]

FIG. 1 is a diagram showing an entire embodiment of the present invention, FIG. 2 is a front view of a flaw detection device, FIG. 3 is a plan view thereof, FIG. 4 is a sectional view of a traction device, and FIG. It is a figure which shows a situation. 1 ... Traction device, 29 ... Support arm, 30 ... Bogie, 42 ... Ultrasonic probe, 63, 66 ... Coil spring (elastic member).

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masaki Ebisawa 3-2-4 Ozone, Kohoku Ward, Yokohama City, Kanagawa Prefecture (56) Bibliographic Reference Shoko 46-16316 (JP, Y1)

Claims (1)

[Claims] 1. A frame fixed to a traction device that travels while adsorbing to a wall surface, a support arm pivotally attached to the frame, and a bogie pivotally attached to a free end of the support arm. A probe that is attached to the trolley and rolls or slides along the wall surface as the trolley travels; and between the frame and the trolley or arm is an elastic member that presses the trolley against the wall surface. The automatic non-destructive inspection device is characterized in that a member is provided and a rotation angle of the arm is regulated within a predetermined range by a stopper.