JPH06160358A - Automatic ultrasonic flaw detector - Google Patents

Abstract

PURPOSE:To provide an automatic ultrasonic flaw detector that allows, at a joint welding part, entirely automatic flaw detection, with high efficiency and precision, and compact configuration for easy handling, over the entire range in the direction of a line of welding containing a plate end, so as to significantly contribute to work efficiency improvement for a large to-be- examined body, etc. CONSTITUTION:A carriage 1, detachably mounted on a plate material, joint welded, with a roller 9 for driving for running in between, that runs in the direction of a line of welding of the plate material, a scan mechanism 2, mounted on the carriage 1, that moves in the direction of welding line and also in the direction orthogonal to it, and a probe 20, attached to the scan mechanism 2, that preforms ultrasonic flaw detection with a joint welding part 4 of the plate material, are provided. The carriage 1 is provided with stop means 14 and 15 that detect the plate end in the direction of welding line so as to stop its running at the position of plate end, meanwhile, scan range is set to the scan mechanism 2 for flaw-detecting the welding part of plate end at the stop position of the carriage 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic ultrasonic flaw detector applied to weld defect inspection of joint welds, and particularly to an automatic ultrasonic inspection suitable for defect inspection of corner joint welds of box columns for building steel frames. The present invention relates to an ultrasonic flaw detector.

[0002]

2. Description of the Related Art Conventionally, when inspecting welding defects such as steel for buildings and steel for bridges, an ultrasonic probe is scanned along the surface of the object to be welded based on the defect length and echo height. Ultrasonic flaw detection technology for evaluating defects is known. In such ultrasonic flaw detection, until now, it was often dependent on the operator's manual scanning, but in addition to requiring a high degree of skill, there is a marked decrease in work efficiency as the size of the subject increases. Therefore, it is desired to improve efficiency and inspection accuracy.

[0003]

Therefore, in recent years, an automatic ultrasonic flaw detection technique for automatically scanning an ultrasonic probe has been developed,
Although the scanning speed has been increased and the scanning has been made more precise, the ultrasonic flaw detection technology that has been developed so far has laid a rail above and to the side of the subject, and a trolley that travels on this rail. However, there are problems that the structure is large and the handling is troublesome, such as scanning of the ultrasonic probe, and the work efficiency cannot always be sufficiently improved.

Further, in the conventional automatic ultrasonic flaw detection technique in which the carriage is arranged above the subject and the carriage and the ultrasonic probe are moved along the welding line direction, the plate along the welding line direction is used. In some cases, flaw detection could not be performed at the edge, resulting in incomplete flaw detection.

The present invention has been made in view of such circumstances, and flaw detection of a joint welded portion can be performed automatically over the entire range in the welding line direction including the plate edge with high efficiency and high accuracy. It is an object of the present invention to provide an automatic ultrasonic flaw detector that has a compact structure, is easy to handle, and can greatly contribute to improving the work efficiency of a large-sized subject or the like.

[0006]

In order to achieve the above-mentioned object, the present invention is detachably mounted on a joint-welded plate through a roller for traveling drive, and is mounted in a welding line direction of the plate. A carriage traveling along the carriage, a scanning mechanism attached to the carriage and movable in a direction along the welding line and in a direction orthogonal to the welding line, and ultrasonic flaw detection of a joint weld portion of the plate material attached to the scanning mechanism. An automatic ultrasonic flaw detector with a probe, wherein the carriage is provided with a stop means for detecting the plate edge along the welding line direction and stopping the traveling at the plate edge position, while the scanning mechanism includes: It is characterized in that a scanning range for detecting a welded portion at the plate edge is set at the stop position of the carriage.

[0007]

According to the present invention, the carriage is mounted on the plate material via the roller and the scanning mechanism is provided, so that the structure is compact and the handling is easy.

The scanning mechanism is movable in a direction along the welding line and in a direction orthogonal to the welding line, and a probe for ultrasonic flaw detection is provided on the scanning mechanism so that it can be automatically operated by each operation of the carriage and the scanning mechanism. In addition, it is possible to detect the welded portion with high efficiency and high accuracy, and it is possible to greatly contribute to the improvement of the work efficiency of a large-sized object or the like.

In addition, the carriage is provided with a stop means for detecting the plate edge along the welding line direction and stopping the traveling at the plate edge position, while the scanning mechanism detects the welded portion of the plate edge at the carriage stop position. By setting the scanning range to be performed, flaw detection of the joint weld portion can be completely performed over the entire range in the welding line direction including the plate edge.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows the overall structure, FIG. 2 shows the structure of the truck, and FIG. 3 shows the operation.

The present embodiment relates to an automatic ultrasonic flaw detector for full-line flaw detection in which the corner welded portion of the box column is simultaneously inspected for four lines and over the entire line, and is roughly classified to perform a general operation over the entire flaw detection range. It is composed of a dolly 1 and a scanning mechanism 2 attached to the dolly 1 for performing flaw detection scanning within a certain range.

As shown in FIGS. 1 and 2, the carriage 1 is removably mounted on the flange 3a of the box pillar 3 which is the subject, and automatically travels along the welding selection direction (x direction) of the corner welded portion 4. This trolley 1 is configured to be divided into left and right by a main trolley 1a and an auxiliary trolley 1b, and both trolleys 1a and 1b are connected by a width adjusting mechanism 6 with an operation handle 5,
It can be installed according to the width of the box pillar 3 of various sizes.

Both carriages 1a, 1b have a plurality of support wheels 7 on the peripheral side of the bottom and a plurality of guide rollers 8 for restricting the planar position on the outer side opposite to each other, and the box pillar 3 placed horizontally. The supporting wheels 7 are mounted on the surface of the flange 3a which is the upper plate, and the guide rollers 8 are brought into contact with the webs 3b which are both outer plates of the box column 3 to be movable in the longitudinal direction of the box column 3. There is.

The main carriage 1a is provided with a traveling roller, for example, a magnet roller 9 at the center of the bottom thereof. The magnet roller 9 is connected to a traveling motor 10 via a transmission mechanism 11 such as a gear device, and a box. It is magnetically joined to the column 3 and is driven so as to be rotatable in the forward and reverse directions. The magnet roller 9 can be moved up and down to the bottom of the main carriage 1a by the attachment / detachment handle mechanism 12, and when the magnet roller 9 is raised, the magnetic joining with the box pillar 3 is eliminated, and the main carriage is removed. It can be attached to and detached from the box pillar 3 of 1a.

The traveling motor 10 includes a traveling axis encoder 1
3 is connected, whereby the mileage of the truck is obtained.
In addition, front and rear plate edge detection switches 14, which are limit switches at the front and rear end positions of the main carriage 1a, include limit switches for detecting both longitudinal end positions of the box column 3 when moving forward and backward.
15 is provided, and the traveling motor 10 is stopped by the detection signals of the plate edge detection switches 14 and 15. The carriage 1 is provided with a marker 16 for marking a stop position, that is, a flaw detection position, so that the flaw detection position can be visually confirmed.

The scanning mechanism 2 is provided in a pair on the side portion corresponding to the guide roller 8 of the carriage 1, that is, on the left and right sides. Each scanning mechanism 2 is supported by a guide shaft 17 on the side of the bogie 1 and moves in a certain range in the bogie running direction (x direction), and a slider 18 moves in a vertical direction (y direction) orthogonal to the bogie running direction. It has a supporting arm 19 for supporting the ultrasonic probe 20, and the ultrasonic probe 20 is attached to the supporting arm 19.

That is, the slider is engaged with the ball screw 22 driven by the X-axis motor 21 and can reciprocate in the x direction. The support arm 19 has, for example, a rack structure, is connected to the Y-axis motor 23 via a pinion 24, and can reciprocate in the y direction. In addition, 25 is an X-axis encoder for measuring the moving distance of the slider 18, 2
6 is a limit switch for similarly setting the movement limit, 27 is a Y-axis encoder for measuring the movement distance of the support arm 19,
28 is a stopper for setting the lower limit.

A total of four ultrasonic probes 20 are provided on each of the support arms 19 in pairs, one above the other, corresponding to the corner welded portions 4. Each of the ultrasonic probes 20 is supported by a so-called gimbal mechanism in a state capable of three-dimensional operation,
It is possible to swing in the x, y, and z directions so that stable scanning and surface tracking can be performed with respect to undulations of the flaw detection surface. Scanning mechanism 2 having such an ultrasonic probe 20
Is set to a scanning range for flaw detection of the welded portion 4 even at the bogie stop position at the plate end.

Next, the operation will be described with reference to FIG.

First, the truck 1 is mounted on the flange 3 of the box pillar 3.
a The ultrasonic probe 20 is mounted on an arbitrary position near the starting end 3A, which is one plate end of the upper surface, the ultrasonic probe 20 is arranged on the outer surface of the web 3b corresponding to each corner welding portion 4, and the slider 18 of the scanning mechanism 2 is arranged. Set to near the origin position (retracted position (left side in the figure)) and start.

After the start, the bogie 1 is temporarily retracted by a bogie traveling control mechanism (not shown), positioned at a starting end portion (origin) 3A which is one plate end of the box column 3 and stopped (see position a in FIG. 3). .

In this state, the scanning mechanism 2 is activated, the ultrasonic probe 20 begins to move forward (moves to the right side in the figure), and scanning is started. When the first scan is completed, the carriage 1 advances by a certain distance and stops, and the ultrasonic probe 20 that has retracted again moves forward again to perform the second scan. Similarly, the third and subsequent scans are repeated, and the automatic continuous ultrasonic flaw detection is performed by the reciprocating operation of the scanning mechanism 2 each time the carriage 1 is stopped.

In the present embodiment, for the above-described flaw detection scanning, for example, rough flaw detection with a large movement pitch and precision flaw detection with a small movement pitch are selectively performed by an appropriate combination. In addition, as a flaw detection method, the ultrasonic probe 20 is used.
An ultrasonic wave is sent out as a transmission wave from the oblique-angle flaw detection oscillator to the corner welding portion 4, and a welding defect or the like is generated while the ultrasonic probe 20 is square-scanned along the scanning line a having a predetermined scanning pitch. The reflected wave from is detected, the echo height and the defect length, etc. are obtained by an ultrasonic flaw detector (not shown), and the pass / fail of welding is determined.

Then, scanning is performed up to the terminal end 3B which is the other plate end, and the ultrasonic flaw detection is completed (see position B in FIG. 3). That is, when the carriage 1 advances to the terminal end portion 3B of the box pillar 3, the limit switch 15 detects the plate edge of the box pillar 3 to stop the carriage 1, and at this position, scanning to the end portion 3B is performed. As a result, flaw detection of the entire welding line is performed. After this, the trolley 1 is the origin (starting point)
It moves backward to 3A and the work ends.

The inspection result is sequentially recorded by a recording means or the like, and printed out if necessary.

According to the automatic ultrasonic flaw detector of this embodiment,
Since all four corner welded portions 4 of the box column 3 can be flaw-detected at the same time, flaw detection work, which is extremely difficult due to the large-sized member, can be carried out with a considerably higher efficiency than in the conventional case. Further, by adopting a function division system in which the carriage 1 performs a general traveling operation and the scanning mechanism 2 performs detailed flaw detection scanning, the flaw detection operation is simplified, the speed is increased, the operation reliability is improved, and the flaw detection accuracy is improved. Can be achieved.

Particularly, according to the ultrasonic flaw detector of this embodiment,
The trolley 1 and the scanning mechanism 2 are compactly integrated to improve the convenience of handling and, for example, the magnet roller 9
As a result, the box pillar 3 can be easily attached to and detached from the upper surface of the flange 3a, and stable traveling can be performed. Therefore, preparatory operations and post-operations can be speeded up as compared with the conventional apparatus.

In addition, the carriage 1 is provided with a stop means for detecting the plate edges 3A and 3B along the welding line direction and stopping the traveling at the plate edge position, while the scanning mechanism 2 is provided with the plate edge at the stop position of the carriage 1. By setting the scanning range for flaw detection of the welded portion 4 of 3A, 3B, flaw detection of the joint welded portion can be performed completely over the entire range in the welding line direction including the plate edge, and one plate end to the other plate end It is possible to detect flaws over the entire range along the longitudinal direction, without leaving any margin.

In the above-mentioned embodiment, the magnet roller is used for traveling the carriage, but a non-magnet type roller may be used, and the apparatus for detecting the four corners of the box-column corner welding portion at the same time has been described. Needless to say, various modifications and applications are possible, such as application to welded objects other than box pillars, application as various methods other than the four-wire simultaneous flaw detection method, and the like.

[0030]

As described above, according to the present invention, the carriage is mounted on the plate material via the roller, and the scanning mechanism is provided. Therefore, the structure is compact, the handling is easy, and the scanning mechanism is welded. It is possible to move in a direction along the line and in a direction orthogonal to it, and a probe for ultrasonic flaw detection is provided on it, so it can be automatically and highly efficiently and accurately by each operation of the carriage and scanning mechanism. It is possible to detect flaws in the welded part, which can greatly contribute to improving the work efficiency of large specimens, etc.
The carriage is provided with a stop means for detecting the plate edge along the welding line direction and stopping the traveling at the plate edge position, while the scanning mechanism is set with a scanning range for flaw detection of the weld edge of the plate edge at the carriage stop position. As a result, an excellent effect such that flaw detection of the joint welded portion can be completely performed over the entire range including the plate edge in the welding line direction is exhibited.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a diagram showing a bogie structure in the embodiment.

FIG. 3 is an operation explanatory view of the same embodiment.

[Explanation of symbols]

 1 cart 2 scanning mechanism 3a plate material (flange of box pillar) 3A, 3B plate end 4 joint weld 9 roller (magnet roller) 14, 15 stop means (limit switch) 20 probe

Claims (1)

[Claims] 1. A dolly that is detachably mounted on a joint-welded plate through a roller for driving the running, and runs along a welding line direction of the plate, and a dolly attached to the dolly and along the welding line. An automatic ultrasonic flaw detector having a scanning mechanism movable in a direction and a direction orthogonal thereto, and a probe attached to the scanning mechanism for ultrasonic flaw detection of a joint weld portion of the plate material, the cart comprising: On the other hand, while the stop means for detecting the plate edge along the welding line direction and stopping the traveling at the plate edge position is provided, the scanning mechanism has a scanning range for flaw detection of the welded part of the plate edge at the stop position of the carriage. An automatic ultrasonic flaw detector characterized by being set.