JP3575565B2 - Ultrasonic probe - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an ultrasonic probe used for ultrasonic inspection of a welded portion of a reactor pressure vessel or the like, and more particularly, to an ultrasonic probe for detecting defects such as blowholes generated in a welded portion of a reactor pressure vessel or the like. The present invention relates to an ultrasonic probe used for flaw detection inspection by using an ultrasonic probe.
[0002]
[Prior art]
In the conventional ultrasonic flaw inspection of a welded portion of a reactor pressure vessel, etc., water is used as a couplant to steadily propagate and inject ultrasonic waves between a contact surface of the ultrasonic probe and a surface to be inspected. Scanning was performed while changing the incident angle of the ultrasonic wave while supplying or once applying a liquid such as glycerin.
[0003]
FIG. 8 is a side sectional view of a conventional ultrasonic probe with a part cut away. Reference numeral 1 denotes an ultrasonic probe (hereinafter, referred to as a "probe"), which is made of acrylic resin or the like. . Then, inside the probe 1, three vibrators 5, 6, 7 constituted by piezoelectric elements or the like are embedded. The vibrators 5, 6, 7 are connected to the connector 12 by signal lines 14, 15, 16 and from there to an external monitoring device (not shown). Further, the three vibrators have different angles of vibrating surfaces. The vibrating surface of the center vibrator 5 is embedded parallel to the contact surface 2 so that the ultrasonic wave oscillated by the vibrator 5 is incident on the object to be inspected at a refraction angle of 0 °. The two vibrators 6 and 7 have a predetermined angle with the vibrating surface facing one long side of the contact surface 2 so that the ultrasonic wave enters the test object at a refraction angle of 45 ° and 60 °. Each is embedded. A groove 3 for supplying a couplant (hereinafter referred to as “water”) is formed in the contact surface 2, and two couplant supply holes 4 (hereinafter “water supply holes”) are formed at the lower end of the groove 3. ), And are connected to a pump (neither is shown) through a water hose. Reference numeral 10 denotes a water hose joint, and reference numeral 11 denotes a fixture for attaching the probe 1 to an inspection device or the like (not shown).
[0004]
FIG. 9 is a view taken in the direction of arrows AA in FIG. 8. The contact surface 2 of the probe 1 is provided with a U-shaped groove 3 having an opening formed downward, and a lower end thereof. Is provided with two water supply holes 4.
[0005]
When performing the flaw detection inspection using the probe 1, the probe 1 is attached to an inspection device (not shown) by the fixture 11, and is pressed against the inspection surface of the inspection object by a spring or the like (not shown). Ultrasonic waves are simultaneously oscillated by vibrators 5, 6, and 7 having three types of refraction angles, and the ultrasonic waves are emitted toward the object to be inspected. Then, the reflected wave reflected from the test object and returned is received, amplified through an amplifier, sent to an oscilloscope, and visually inspected for the magnitude of the waveform while automatically scanning. At this time, in order to propagate and make an accurate and stable ultrasonic wave between the contact surface 2 of the probe 1 and the surface to be inspected, a groove 3 provided in the contact surface 2 is provided at a lower end thereof. For example, water flows from the individual water supply holes 4 and scanning is performed while changing the direction of the ultrasonic wave.
[0006]
[Problems to be solved by the invention]
However, the inspected object for which the flaw detection is to be performed is generally arranged in a vertical direction in many cases, and the surface of the inspected surface is not always flat. Further, in the conventional probe 1, the groove 3 for supplying water provided on the contact surface 2 is formed in a U-shape so that the opening is directed downward. Since the water is supplied from the two water supply holes 4 provided in communication with the lower end, the water flows downward by gravity, and the water that should have reached the upper part through the groove 3 does not reach. Therefore, the portion for transmitting ultrasonic waves between the inspection surface and the contact surface 2 is not sufficiently filled with necessary water. For this reason, there has been a problem that accurate ultrasonic waves are not incident and the flaw detection sensitivity is reduced. Further, the ultrasonic waves emitted from the vibrators 6 and 7 emitted obliquely upward due to the grooves on the upper side were disturbed, which also affected the flaw detection sensitivity.
[0007]
The present invention is intended to solve the above-described conventional problems. The space between the surface to be inspected and the probe surface 2 is sufficiently filled with water, and the space between the surface to be inspected and the probe surface 2 is accurate without any influence from the groove. It is an object of the present invention to provide an ultrasonic probe capable of transmitting and entering stable ultrasonic waves.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, according to a first aspect of the present invention, there is provided a box-shaped ultrasonic probe in which a contact surface with a surface to be inspected has a rectangular shape and a vibrator is embedded therein. Three vibrating surfaces are buried parallel to the contact surface in the center vibrator, and two vibrators on both sides of the vibrating surface are buried in one long side of the contact surface. The contact surface is provided with a groove for supplying a couplant between the contact surface and the surface to be inspected, and the shape of the groove is a large Chinese character. The central vibrator is located at the position surrounded by the square-shaped part of the giant figure, and the two vibrators on both sides are the square-shaped part of the giant figure. And the L-shaped and inverted L-shaped portions forming both sides of the square shape, respectively, are arranged, and the giant vertical line is Serial and along the two long sides towards the vibrating surface does not face the vibrator on both sides, moreover, is provided in communication with at least four corners couplant supply hole of the groove.
[0009]
In the second invention, a box-shaped ultrasonic probe having a rectangular contact surface with the surface to be inspected and having a vibrator embedded therein, wherein three vibrators are embedded in the long side direction. Of these three vibrators, one of the ends has a vibrating surface embedded in parallel with the contact surface, and the other two vibrating surfaces face the direction of one long side of the contact surface. The contact surface is provided with a groove for supplying a couplant between the contact surface and the surface to be inspected, and the shape of the groove is such that the vibrating surface is embedded parallel to the contact surface. A vibrator is formed at the position of the vibrator, and an L-shape is formed at the positions of the other two vibrators, and one side is the same as one side of the U-shape. communicates in a straight line, shape of one side of the L in communication with the shaped side of the b is not the plane of vibration of the other two transducers are oriented There way is along the long side of, moreover, is provided in communication with at least four corners couplant supply hole of the groove.
[0010]
According to the configuration of the present invention described above, even when the flaw detection inspection is performed under the condition that the direction of the inspection surface of the inspection object is vertical or oblique, Since it is supplied from four corners, it can reach the upper part sufficiently, so that an accurate and stable ultrasonic wave can be propagated and incident on the inspected object, and an accurate and stable reflected wave can be reflected from the inspected object. Propagate and receive.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. Note that the same reference numerals are used for members common to those of the related art, and description thereof is omitted.
1 is a front view of the probe 1 of the present invention, FIG. 2 is a rear view of the probe shown in FIG. 1, FIG. 3 is a side view of the probe with a part cut away, and FIG. FIG. 5 is a schematic diagram showing a state in which the probe is used while the probe is in contact with the surface to be inspected of the object to be inspected, FIG. 5 is a waveform diagram of ultrasonic waves displayed on an oscilloscope, and FIG.
[0012]
1 to 3, reference numeral 1 denotes a rectangular and box-shaped probe made of acrylic resin or the like. Further, three vibrators 5, 6, and 7 each composed of a piezoelectric element or the like are embedded in the probe 1 (FIGS. 1 and 2). The vibrators 5, 6, and 7 are connected to the connector 12 via signal lines 14, 15, 16 (FIG. 3), and from there to an external monitoring device (not shown). Further, the three vibrators have different angles of vibrating surfaces. The vibrating surface of the center vibrator 5 is embedded parallel to the contact surface 2 so that the ultrasonic wave oscillated by the vibrator 5 is incident on the test object at a refraction angle of 0 °. The two vibrators 6 and 7 have a predetermined angle with the vibrating surface facing one long side of the contact surface 2 so that the ultrasonic wave enters the test object at a refraction angle of 45 ° and 60 °. Each is embedded. In addition, these structures are the same as the conventional probe. As shown in FIG. 1, the contact surface 2 is provided with a groove 3 having a large kanji character, and the vertical line of the large character is the long side of the probe 1. Are provided in parallel along. The central vibrator 5 is disposed at a position surrounded by a square-shaped portion of the large character, and the two oscillators 6 and 7 on both sides are square-shaped in the large character. , And the L-shaped and inverted L-shaped portions forming both sides of the square. The giant vertical line extends along the long side of the two vibrators 6 and 7 on both sides where the vibrating surface is not facing. Four water supply holes 4 are provided at four corners of the groove 3 so as to communicate with each other, and are connected to a hose joint 10 which is connected to an external water supply device (not shown). At the time of inspection, water is supplied from the water supply hole 4 to the surface to be inspected. Reference numeral 11 denotes a fixture for attaching the probe 1 to an inspection device or the like. The reason why the grooves 3 along the long sides of the vibrators 6 and 7 at both ends are provided only on one long side and not provided on the other long side is that the grooves 3 are provided on the other side. The reason is that the oscillation and reception of the ultrasonic wave are affected by the groove 3, and it is difficult to detect an accurate reflected wave.
[0013]
FIG. 4 is a schematic view showing a state in which the probe 1 is in contact with the inspection surface P1 of the inspection object P and is in use, and reference numeral 13 denotes water supplied between the inspection surface P1 and the contact surface 2. It is.
[0014]
FIG. 5 is a waveform diagram of an ultrasonic wave displayed on an oscilloscope which is a monitoring device, where d represents a path to a defect existing in the inspection object P (FIG. 6), and t and 2t are obtained from the same defect. The peak value is shown. Here, t is the magnitude of the reflected echo from the defect obtained by the inspection performed by using the conventional probe 1, and 2t is the size of the reflected echo by the inspection performed by using the probe 1 of the present invention. The magnitude of the reflected echo from the obtained defect is shown.
[0015]
FIG. 6 is a conceptual diagram of use of the present invention. Then, as in FIG. 4, the probe 1 is pressed against the inspection surface P1 of the inspection object P, and the monitoring is performed by the amplifier 8 and the oscilloscope 9 as the monitoring device.
[0016]
Next, the operation of the embodiment will be described.
When performing the flaw detection inspection of the inspection object P with the probe 1 configured as shown in FIGS. 1 to 3, the probe 1 is attached to an inspection device or the like (not shown) by the fixture 11. A spring 13 or the like (not shown) presses against the surface to be inspected of the object to be inspected, and water 13 flows through a groove 3 provided between the surface to be inspected and the contact surface 2 to remove a gap formed therebetween. Fill well with water. Next, as shown in FIGS. 4 and 6, the probe 1 is pressed against the inspection surface P1 of the inspection object P, and the ultrasonic waves generated by the transducers 5, 6, 7 are emitted toward the inspection object P. Then, the ultrasonic wave reflected and returned from the test object P is received and amplified through the amplifier 8, and then sent to the oscilloscope 9, where the size of the waveform is visually inspected while automatically scanning.
[0017]
FIG. 7 shows another embodiment of the present invention. Reference numeral 1 denotes a rectangular and box-shaped probe made of acrylic resin or the like. In addition, three vibrators 5, 6, and 7 composed of a piezoelectric element or the like are embedded in the probe 1, and these configurations are the same as those in the embodiment of the present invention. . The above embodiment is different from the above-described embodiment in that the center vibrator 5 is provided at the end of the three vibrators 5, 6, 7, and the vibrators 6, 7 are arranged side by side. The groove 3 for supplying the liquid crystal is formed in a rectangular shape so as to surround the vibrator at the position of the vibrator 5, and is formed in the shape of an L at the positions of the vibrators 6 and 7, and one side thereof is formed in the shape of the rectangular shape. It is different in that it communicates with one side of the U-shape in the same straight line. One side of the L-shape communicating with this one side of the square is along the long side of the other two vibrators that does not face the vibrating surface. It should be noted that the water supply holes 4 are provided at at least four corners of the groove 3 so as to communicate with each other, which is the same as the above embodiment.
[0018]
According to the results of experiments conducted by the inventor, when water 13 was supplied from the four corners of the groove 3 according to the present invention, as shown in FIG. Since the sensitivity is improved, the wave height displayed on the oscilloscope 9 of the monitoring device is increased. As a result, it has been confirmed that the problem that the defect is judged to be acceptable because the flaw detection conditions are poor and the height of the reflected echo from the defect does not increase can be solved.
[0019]
【The invention's effect】
As described above, according to the present invention, water is supplied from at least four corners to the water supply groove formed on the contact surface of the probe, so that the gap between the contact surface and the inspection surface is water. Fully satisfied. In addition, since there is no groove near the long side of the contact surface in the direction that the transducers on both sides are facing, ultrasonic waves emitted obliquely are not disturbed, and accurate and stable This has the effect of allowing the transmitted ultrasonic waves to propagate and enter.
[Brief description of the drawings]
FIG. 1 is a front view showing an embodiment of a probe according to the present invention.
FIG. 2 is a back view of the probe shown in FIG. 1;
FIG. 3 is a right side view in which a part of the probe of the present invention is cut away.
FIG. 4 is a schematic diagram showing a state in which a probe is used by being pressed against a surface to be inspected of an object to be inspected.
FIG. 5 is a waveform diagram of an ultrasonic wave displayed on an oscilloscope.
FIG. 6 is a conceptual diagram of use of the present invention.
FIG. 7 is a front view showing another embodiment of the present invention.
FIG. 8 is a right side view in which a part of a conventional probe is cut away.
FIG. 9 is a front view showing an embodiment of a conventional probe.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Ultrasonic probe 2 Contact surface 3 Groove 4 Water supply holes 5, 6, 7 Transducer 8 Amplifier 9 Oscilloscope 10 Hose joint 13 Water 14, 15, 16 Signal line P Inspection object P1 Inspection surface

Claims (2)

A box-shaped ultrasonic probe having a rectangular contact surface with the surface to be inspected and a vibrator embedded therein,
Three vibrators are buried side by side in the long side direction, and the vibrating surface of the central vibrator is buried in parallel with the contact surface, and the two vibrators on both sides have the vibrating surface of one of the contact surfaces. It is embedded at a predetermined angle in the direction of the long side, and a groove for supplying couplant is provided between the contact surface and the surface to be inspected, and the shape of the groove is a large Chinese character Jodea is, the center of the vibrator is disposed at a position surrounded by the shaped portion of the furnace of the giant-shape, each side of the two vibrators are giant hollow square of shaped Are arranged between the L-shaped portion and the L-shaped and inverted L-shaped portions forming both sides of the square, respectively. is along the two long sides towards the vibrating surface does not face the vibrator, moreover, is provided in communication with at least four corners couplant supply hole of the groove Ultrasonic probe is characterized and. A box-shaped ultrasonic probe having a rectangular contact surface with the surface to be inspected and a vibrator embedded therein,
Three vibrators are embedded side by side in the long-side direction, and among the three vibrators, one end has a vibrating surface embedded parallel to the contact surface, and the other two vibrators are vibrated. The surface is embedded at a predetermined angle in the direction of one long side of the contact surface, and the contact surface is provided with a groove for supplying a couplant with the surface to be inspected. The shape is such that a square shape is formed so as to surround the vibrator at the position of the vibrator where the vibrating surface is buried in parallel with the contact surface, and an L shape is formed at the positions of the other two vibrators. And one side thereof communicates with the one side of the square in the same straight line, and one side of the L-shape communicating with one side of the square has a shape of the other two vibrators. towards the vibrating surface does not face is along the long side, moreover, that is provided in communication with at least four corners couplant supply hole of the groove An ultrasonic probe and butterflies.

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