JPS6256856A - Ultrasonic test equipment - Google Patents

Abstract

PURPOSE:To automate the flaw detection of the peripheral weld zone of a curved tube by pressing an arm and an ultrasonic probe against a sample independently of each other. CONSTITUTION:When the arm 4 is pressed against an arm pressing part 5 by using an air cylinder, etc., the arm 4 rotates around a support point 13 and a roller 11 contacts a curved tube part 1. The direct force of the pressing part 5, therefore, operates on the roller 11 and does not operate on the ultrasonic probe 9. Further, only the probe 9 is pressed by a probe pressing part 12 which uses the air cylinder, etc., so that the probe 9 is pressed against the surface of piping 1 with constant pressure. Consequently, the flaw detection of the peripheral weld zone of the curved tube is automated.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to an ultrasonic flaw detection device for inspecting welded portions of piping and the vicinity thereof by ultrasonic flaw detection, particularly for inspecting welded portions of curved portions of piping. This invention relates to an ultrasonic flaw detection device suitable for

[Background of the invention]

Ultrasonic flaw detection tests are generally performed to inspect the volume of pipe welds in nuclear power plants and the like. In this ultrasonic flaw detection test, it is necessary to always press the probe against the pipe with a constant pressing force and scan the pipe.

Conventionally, ultrasonic flaw detection of curved pipes has been carried out manually by inspectors, or by scanning a probe as in Japanese Patent Application Laid-Open No. 56-39459, and flaw detection data has been automatically imported. The process is carried out using a semi-automatic drive device.

Semi-automatic drive with orbit 1. Consists of a drive unit, an arm, and an ultrasonic probe unit. The arm can rotate like a seesaw, but the control of the seesaw-shaped rotation and the movement of the ultrasonic probe unit in the arm direction is up to the inspector. However, only movement in the orbital direction was performed by the drive unit.

Recently, there has been a growing trend to automate ultrasonic flaw detection tests for welded parts of curved pipes, and various proposals have been made.

Japanese Patent Laid-Open No. 58-24857 proposes a mechanism in which the flaw detection arm has a multi-stage structure and an arm for curve tracing is provided at the tip of the flaw detection arm. In this example, the extension and contraction of the flaw detection arm and the scanning of the probe in the pipe axis direction are performed by a combination of a plurality of gears and a power transmission shaft. Therefore, the positioning error of the probe in the pipe axis direction is large. Furthermore, since the arm for tracing curves is provided, there are problems such as the ease of transport and attachment and detachment of the device.

[Purpose of the invention]

The present invention solves the problems of the prior art, and its purpose is to automate ultrasonic flaw detection of welded parts of piping, especially circumferential welded parts of curved pipes, and to An object of the present invention is to provide an ultrasonic flaw detection device capable of scanning an ultrasonic probe according to changes.

[Summary of the invention]

The present invention relates to an ultrasonic flaw detection device for curved pipes, in which pressing of the arm and pushing of the ultrasonic probe are carried out independently, and the ultrasonic probe is suitable for scanning along the curved pipe. It is a flaw detection device.

[Embodiments of the invention]

An embodiment of the present invention is shown in FIG.

As shown in the figure, the ultrasonic flaw detection device of the present invention has trajectory 2,
A drive device 3, a rotatable arm 4, an arm pressing section 5, a drive screw 6, an arm direction drive section 7, a probe holder 8, an ultrasonic probe 9, and a roller 1 attached to the other end of the arm.
1. The probe pressing section is composed of a section 12 and the like.

Now, when the arm is pressed against the section 5 using, for example, an air cylinder, the arm rotates about the support point 13 in the direction of the arrow 10, and the roller 1 comes into contact with the bent pipe section 1. . The arm 4 is now supported by the support point 13 and the roller 1.

Therefore, in this method, the direct force of the arm pressing section 5 acts on the roller 11 and does not act on the ultrasonic probe 9.

The ultrasonic probe 9 can be pressed on the surface of the piping 1 by pressing only the ultrasonic probe 9 through the part 12, using a separate air cylinder or the like. It becomes possible to press the probe 9 against the surface with a constant pressure.

An example of application to a straight pipe/elbow weld will be described in detail with reference to FIGS. 2 to 4.

FIG. 2 is a diagram showing a situation in which flaws are being detected on the back side of the elbow. The ultrasonic probe 9 is scanned along the convex surface of the curved tube part l with the zero point as the center, and the ultrasonic beam 14 is directed downward to detect flaws in the flaw detection range 15 required by the standard. The ultrasonic probe 9 is pressed by a probe pressing section 12 provided on the probe holder 8 . On the other hand, the roller 1 is pressed and attached to the bent pipe part 1 by the arm pressing part 5.

FIG. 3 is a diagram showing a situation in which flaws are being detected on the side surface of the elbow. In the case of the side of the elbow, it becomes a nearly straight surface, so
The arm 4 is also kept horizontal, and the relationship between the ultrasonic probe 9 and the probe pressing section 12 is maintained under ideal conditions.

FIG. 4 is a diagram showing a situation in which flaws are being detected on the ventral side of the elbow. The ultrasonic probe 9 is scanned along the concave surface of the curved pipe section 1 with the 0 point as the center, and the ultrasonic beam 14 is directed upward to detect flaws in the flaw detection range 15 required by the standard. In this case, since the object surface is a concave surface, the roller 11 is at the highest position and the stroke of the probe pressing section 12 is the longest.

As mentioned above, in the case of ultrasonic flaw detection of the curved pipe section 1, the ultrasonic probe 9 is scanned by sufficiently following various surfaces such as convex surfaces, straight surfaces, and concave surfaces to perform flaw detection as required by the standard. It is necessary to inject the ultrasonic beam 14 into the range 15, but as shown in FIGS. 2 to 4, the rotatable arm 4, arm pressing part 5, and roller 1
1. It can be seen that probe pressing can be sufficiently achieved by configuring the function of the section 12 and the like.

5 to 7 are detailed explanatory diagrams of the drive device 3 portion of FIG. 1.

In FIG. 5, the top surface is shown, and the drive device 3 is equipped with a motor for driving in the orbital direction (X-axis circumferential motor) 16, a shaft encoder for detecting the position in the orbital direction (X-axis circumferential encoder) 17,
The drive is transmitted through a pinion (not shown), and the position and direction of the ultrasonic probe 9 in the circumferential direction of the pipe 1 is controlled. The arm direction drive unit 7 includes an arm direction drive motor (Y-axis motor) 8 and a shaft encoder (Y-axis circumferential encoder) 19 for arm direction position detection, and the Performs driving and position detection.

FIG. 6 is an elevational view. The Y-axis circumferential motor 18 and encoder 19 are connected to the drive screw 6 via a gear (not shown). The arm 4, the drive screw 6, the arm direction drive section 7, etc. are integrated and mounted so as to be rotatable about the support point 3.

FIG. 7 is a side view. Although the attachment/detachment device for the track 2 and the drive device 3 is not shown here, they can be attached and detached with a single touch.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to perform fully automatic ultrasonic flaw detection of welded parts of piping, especially curved pipes, and constant pressing can be performed by scanning the ultrasonic probe with force. By automating flaw detection inspections of curved pipe welds, which were previously carried out manually or by semi-automated equipment by inspectors, it has the effect of reducing radiation exposure during in-service inspections of nuclear power plants, etc. It will be done.

[Brief explanation of drawings]

Fig. 1 is a perspective view of the overall configuration of an ultrasonic flaw detection device according to an embodiment of the present invention, Fig. 2 is an explanatory view of the back side flaw detection situation of the elbow, and Fig. 3 is an explanatory view of the side flaw detection situation of the elbow, 2J4. The figure is an explanatory diagram of the flaw detection situation on the ventral side of the elbow, and Figure 5 is the one shown in Figure 1.
Detailed top view of 3 parts, Figure 6 is also a detailed elevation view, Figure 7
The figure is also a side view. J... Piping (bent pipe), 2... Track, 3... Drive device, 4... Arm, 5... Arm pressing part, 7...
・Arm direction drive unit, 8... Probe holder, 9...
Ultrasonic probe, 11... Roller, 12... Ultrasonic probe pressing part.

Claims (1)

[Claims] 1. A drive device that is movable relative to the subject, a rotatable arm mounted on the drive device, an ultrasound probe held movably along the arm, and a probe provided at the tip of the arm. an arm pressing unit that presses the arm against the subject so that the roller contacts the subject; and an ultrasound probe that presses the ultrasound probe movably toward the subject against the arm. An ultrasonic flaw detection device consisting of a pressing part.