JPH07181171A - Ultrasonic flaw-detector - Google Patents

Abstract

PURPOSE:To provide a small, lightweight and easily-detachable ultrasonic flaw- detector for detecting a flaw in a straight pipe, an elbow welded part, etc., by a method wherein a probe movement part installed at a circumferential ring is provided with a first ultrasonic probe and a probe holding arm installed at the probe movement part is provided with a second ultrasonic probe. CONSTITUTION:A circumferential ring 24 is supported by rollers 25, 26 for circumferential ring support, and it is driven by pinions 27, 28 for circumferential ring drive. A probe movement part 31 is attached to an arm 6 installed at the ring 24. An air cylinder 32, a probe mounting part 33, an ultrasonic probe 7, a probe mounting part 34, an air cylinder 35, a probe support arm 36 and an ultrasonic probe 37 are attached to the movement part 31. The probes 7, 37 are held by the arm 36 in the length direction of a pipe with reference to one probe movement part 31. As a result, the arm 6 becomes short by the protruding-length portion of the arm 36, and a curved part such as an elbow or the like in the pipe does not constitute an obstacle. In addition, a load which is applied to the circumferential ring is reduced. and also a driving gear can be miniaturized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic flaw detector,
In particular, the present invention relates to an ultrasonic flaw detector for piping, which is suitable for performing remote automatic ultrasonic flaw detection of a welded portion of a primary cooling system pipe of a nuclear power plant, for example.

[0002]

2. Description of the Related Art An ultrasonic flaw detector of this type that has been generally adopted in the past has a circular ring guide portion installed in the circumferential direction on the surface of a pipe, and a drive unit main body that runs along the track on this orbit. Generally, an arm is extended from the main body of the drive device in the longitudinal direction of the pipe, and the ultrasonic probe is scanned along the arm for ultrasonic flaw detection.

That is, FIGS. 12 and 13 show an outline of the ultrasonic flaw detector for piping, in which 1 is a welded portion 2.
A vertical type orbit 3 extending in the circumferential direction is installed around this pipe, and the drive device main body 4 runs on this orbit 3 via guide rollers 8 and 9. .
That is, the drive device body 4 travels only in the circumferential direction.

Further, an arm 5 extending along the longitudinal direction of the pipe 1 and a ball screw 6 are provided in the drive device main body 4, and the ultrasonic probe 7 is guided by the rotation of the ball screw 6 using the arm 5 as a guide. Run in the longitudinal direction.

That is, the ultrasonic probe 7 is formed so as to be moved in the circumferential direction by the traveling of the drive device main body 4 and to be moved in the longitudinal direction along the arm 5. Due to the movement of both, the ultrasonic probe 7 is
An ultrasonic flaw detection test is performed by scanning the entire area.

As a device related to these ultrasonic flaw detectors, there is JP-A-61-140857.

[0007]

Since the ultrasonic flaw detector formed as described above has a vertical track, it is effective for reducing the height of the drive unit.

However, for example, when ultrasonic flaw detection is performed on the welded portion of the primary cooling system piping of a nuclear power plant,
Other pipes, structures, etc. are often arranged close to the periphery, that is, around the pipe, and the pipe itself may be curved. In such a case, the length of the pipe The arm 5 extending in the direction becomes an obstacle, and it becomes necessary to reattach the orbiting ring guide portion, or it is necessary to prepare a special device such as a shift or a telescopic arm. In, there was a dislike that efficiency decreased.

The present invention has been made in view of the above circumstances, and it is an object of the present invention that the structure is simple and lightweight without using a shift or expansion / contraction device, as well as being small and lightweight and easily attached and detached. It is an object of the present invention to provide an ultrasonic flaw detector of this kind which enables flaw detection of a straight pipe, an elbow welded portion, and the like.

[0010]

That is, according to the present invention, one probe moving unit that moves in the longitudinal direction of the pipe along the arm is provided on the arm provided on the orbiting ring of the drive unit main body. The probe moving arm is provided with a probe holding arm in the longitudinal direction of the pipe, and the first ultrasonic probe is attached to the probe moving part and the second ultrasonic probe is attached to the tip of the probe holding arm. An ultrasonic probe is provided to achieve the intended purpose.

[0011]

In other words, in the ultrasonic flaw detector thus constructed, the probe holding arm is provided in one probe moving part in the longitudinal direction of the pipe, and the probe moving part and the probe moving part are provided. Since each of the probe holding arms is provided with the first and second ultrasonic probes, the tip of the probe holding arm can be scanned until it projects in the longitudinal direction of the pipe from the arm tip, The length of the arm is shortened by this protruding length, that is, the length of the arm is enough to detect flaws on one side of the welded part, so it is possible to shorten the length by the amount required for scanning on the other side, and the elbow on the pipe. Even if there is a curved part such as, the arm is not disturbed, and the length of the arm is short,
The load applied to the orbiting ring is reduced, and a small drive unit is sufficient. Therefore, in one track, the ultrasonic probe can scan the entire area of the weld, and in particular, use a special device such as a shift or telescopic arm. It is possible to detect flaws on straight pipes, elbow welds, etc.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the illustrated embodiments. The ultrasonic flaw detector is shown in FIGS. 1 to 3. The same parts as those in the conventional example described above are designated by the same reference numerals, and detailed description thereof will be omitted.

Reference numeral 20 denotes a revolving ring guide portion, the track of which is mounted upright in the radial direction in the circumferential direction of the pipe. Reference numeral 21 denotes a revolving ring guide attachment portion, which is attached to the direct pipe 1 side of the pipe by tightening with a screw. Reference numeral 22 denotes a revolving ring driving motor, which is attached to the revolving ring guide portion 20.

An encoder 23 outputs a position signal in the circumferential direction. Reference numeral 24 is a revolving ring, 25 and 26 are revolving ring supporting rollers, 27 is a revolving ring driving pinion, 28
Is a orbiting ring drive rack provided on the orbiting ring 24.

The orbiting ring 24 is supported by the orbiting ring supporting rollers 25 and 26, and is driven by the orbiting ring driving pinion 27 and the rack 28.

An arm 5, a ball screw 6, a ball screw driving motor 29, and a probe position detecting encoder 30 are attached to the orbiting ring 24. A probe moving unit 31 is attached to the arm 5, and the probe moving unit 31 is driven by the ball screw 6.

The probe moving section 31 has an air cylinder 32,
First probe mounting portion 33, ultrasonic probe 7, second probe mounting portion 34, air cylinder 35, probe holding arm 3
6. The ultrasonic probe 37 is attached.

It is important to note that the ultrasonic probe 7 and the ultrasonic probe 37 have a probe holding arm 36 in the longitudinal direction of the pipe with respect to one probe moving portion. It is said to be held through.

In the ultrasonic flaw detector formed in this way, one side of the probe holding arm 36 can scan until it protrudes from the tip of the arm in the longitudinal direction of the pipe. No. 5 is shortened, and even if there is a curved portion such as an elbow in the pipe, it does not get in the way.

Since the arm is shortened, the orbiting ring 24
The load applied to the motor is reduced, and a small drive unit is sufficient. Further, according to this embodiment, the orbiting ring drive motor 2 is
By fixing 2 on the pipe to reduce the weight of the movable part and further shorten the arm, the load on the orbiting ring 24 can be significantly reduced, so that the reliability of the position accuracy etc. is not impaired. Further miniaturization is possible, and ultrasonic flaw detection tests in narrow spaces are possible.

The ultrasonic flaw detection in the ultrasonic flaw detector thus formed is performed as follows, as in the conventional case. That is, the ultrasonic probe 7 has one one side scanning range A to
The ultrasonic beam as indicated by 38 is transmitted to the weld portion 2 by scanning between C and C. On the other hand, the ultrasonic probe 3
7 is scanned in the other one-side scanning range D to B,
An ultrasonic beam as indicated by 39 is transmitted to the welded portion 2. In this case, the ultrasonic beams 38 and 39 show the state of transmission at points A and D, respectively.

FIGS. 4 and 5 show another embodiment of the present invention in which the arm 5 can be replaced. That is, reference numeral 40 denotes an arm mounting jig, to which the arm 5, the ball screw 6, and the ball screw driving motor 29 are mounted, and which is detachable from the orbiting ring 24. Attaching and detaching is done with 41 screws. Of course, also in this case, the probe is held via the probe holding arm 36. With this configuration, not only the above-described effect can be achieved, but also an optimum arm can be attached, and an ultrasonic flaw detection test can be performed in a narrower portion.

FIGS. 6 and 7 show still another embodiment. In this case, the probe holding arm 36 is detachable, and FIG. Air cylinder 32, first probe mounting portion 33, ultrasonic probe 7
7 shows a case where the second probe mounting portion 34, the air cylinder 35, the probe holding arm 36, and the ultrasonic probe 37 are mounted on the probe moving portion 31.

In this way, the first and second probe mounting portions 3
It is also possible to attach 3, 34 individually. In addition,
In this case, it should be noted that the probe holding arm on the probe 2 side is formed so as to protrude from the arm 5.

8 and 9 show application examples of the ultrasonic flaw detector for piping according to the present invention. 3 is a vertical track, 4 is a drive unit main body, 8 and 9 are drive unit main bodies 4 are vertical type. A guide roller for attaching to the track 3 and a driving rack 50 provided on the vertical track 3 meshes with the pinion 27 and drives the driving device body 4.

FIG. 10 also shows an application example of the ultrasonic flaw detector for piping of the present invention, in which the shape of the track is changed. In the figure, 60 is a track, and 61 is a drive device main body.

FIG. 11 shows still another example.
In this case, the second probe mounting portion is pressed by the probe pressing portion, and 70 is the probe pressing portion, and 7 is the probe pressing portion.
Reference numeral 1 is the center of rotation of the probe pressing portion 70. In this case, the probe pressing portion 70 acts so as to press the probe 37 against the surface of the pipe 1 by, for example, an air cylinder or a spring.

As described above, the embodiment of the present invention has the following effects. That is, 1) Since the load on the orbiting ring can be reduced, the height of the driving device can be reduced, and the ultrasonic flaw detection test in a narrow space can be performed. 2) Since the length of the arm can be shortened to the length for detecting flaws on the drive unit side of the welded portion, the arm can be miniaturized.

[0029]

As described above, according to the present invention, even if there is a curved portion such as an elbow in the pipe, it does not get in the way, and since the arm is short, the load on the orbiting ring is reduced. Therefore, it is possible to use a small drive device, and therefore, the ultrasonic probe can scan the entire welded portion with one side trajectory, and in particular, the structure is simple and compact without using a special device such as a shift or an extendable arm. It can detect flaws on straight pipes, elbow welds, etc.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing an embodiment of an ultrasonic flaw detector according to the present invention.

FIG. 2 is a plan view showing an embodiment of the ultrasonic flaw detector of the present invention.

FIG. 3 is a front view showing an embodiment of the ultrasonic flaw detector of the present invention.

FIG. 4 is a vertical sectional side view showing another embodiment of the ultrasonic flaw detector of the present invention.

FIG. 5 is a front view showing another embodiment of the ultrasonic flaw detector of the present invention.

FIG. 6 is a vertical cross-sectional side view of a probe mounting portion showing another embodiment of the ultrasonic flaw detector of the present invention.

FIG. 7 is a vertical cross-sectional side view of a probe mounting portion showing another embodiment of the ultrasonic flaw detector of the present invention.

FIG. 8 is a vertical sectional side view showing still another embodiment of the ultrasonic flaw detector of the present invention.

FIG. 9 is a plan view showing still another embodiment of the ultrasonic flaw detector of the present invention.

FIG. 10 is a vertical sectional side view showing still another embodiment of the ultrasonic flaw detector of the present invention.

FIG. 11 is a vertical sectional side view showing still another embodiment of the ultrasonic flaw detector of the present invention.

FIG. 12 is a vertical cross-sectional side view showing a main part of a conventional ultrasonic flaw detector.

FIG. 13 is a side view of a conventional ultrasonic flaw detector.

[Explanation of symbols]

5 ... Arm, 7 ... Ultrasonic probe, 20 ... Orbiting ring guide part, 24 ... Orbiting ring, 31 ... Probe moving part, 33 ... First probe mounting part, 34 ... Second probe Child mounting part, 70 ...
Probe pressing part.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kimio Kanda 3-8-1 Omika-cho, Hitachi-shi, Ibaraki Ibaraki Information Service Co., Ltd.

Claims (8)

[Claims] 1. A revolving ring guide portion removably attached to an outer surface of a pipe, a revolving ring having an arm that moves along the revolving ring guide portion and extends in a longitudinal direction of the pipe, and on the arm. A probe moving part that moves along the arm, a first ultrasonic probe provided in the probe moving part, and a probe holding arm also provided in the probe moving part. ,
It is composed of a second ultrasonic probe provided on the probe holding arm, and holds the first and second ultrasonic probes at a predetermined interval in the longitudinal direction of the pipe. An ultrasonic flaw detector characterized in that 2. The ultrasonic flaw detector according to claim 1, wherein a probe pressing portion is provided instead of the probe holding arm, and the probe is pressed against the surface of the pipe. 3. The ultrasonic flaw detector according to claim 2, wherein the probe pressing portion is formed of an elastic body. 4. The ultrasonic flaw detector according to claim 1, 2 or 3, wherein an arm on which the first and second ultrasonic probes are mounted is detachably formed on the orbiting ring. 5. A track laid on the surface of the pipe in the vicinity of the welded portion, a drive unit main body running along the track, an arm attached to the drive unit and extending in the longitudinal direction of the pipe, An ultrasonic flaw detector equipped with a probe moving unit that moves along an arm and an ultrasonic probe attached to the probe moving unit, wherein flaw detection is performed on the drive unit side of the pipe welding unit. The first probe and the second probe for flaw detection on the side opposite to the driving device are respectively held by the probe holding arm or the tip of the probe pressing portion,
The ultrasonic flaw detector is characterized in that the second probe is formed so as to protrude from the tip of the arm when the probe moving portion moves the maximum. 6. A vertical track laid on the surface of the pipe, an orbital ring running along the side surface of the vertical orbit, a drive device for driving the orbital ring, and attached to the orbital ring, An ultrasonic flaw detector comprising: an arm extending in a longitudinal direction of a pipe; a probe moving unit that moves along the arm; and an ultrasonic probe attached to the probe moving unit, wherein A first probe for flaw-fixing and holding a driving device for driving the orbiting ring on the track side, and a second probe for flaw-detecting the driving device side of the pipe welding portion and a counter-driving device side And a probe holding arm or a probe pressing portion that is respectively held at the tip of the pressing portion, and the second probe is formed so as to project from the tip of the arm in the maximum movement state. Sonic flaw detector. 7. A revolving ring guide portion removably attached to the outer surface of the pipe, a revolving ring having an arm that moves on the revolving ring guide portion and extends in the longitudinal direction of the pipe, and an arm above the arm. An ultrasonic flaw detector comprising: a first and a second ultrasonic probe that move along the arm to detect a weld, and one probe movement that moves along the arm on the arm. And a two-pronged probe holding arm that is divided in the longitudinal direction of the pipe is provided in the probe moving portion, and the first ultrasonic probe is provided at one end of the probe holding arm. An ultrasonic flaw detector, characterized in that a child and the second ultrasonic probe are held at the tip on the other side. 8. A revolving ring guide part removably attached to the outer surface of the pipe, a revolving ring having an arm that moves on the revolving ring guide part and extends in the longitudinal direction of the pipe, and an arm above the arm. An ultrasonic flaw detector comprising: a first and a second ultrasonic probe that move along the arm to detect a weld, and one probe movement that moves along the arm on the arm. And a probe holding arm extending toward the tip end side of the arm and a probe holding arm extending to the surface of the pipe at the shortest distance are provided in the probe moving portion. An ultrasonic flaw detector, characterized in that the first and second ultrasonic probes are respectively held at the tips of the arms.