JPH06331610A - Ultrasonic probe unit - Google Patents

Abstract

PURPOSE:To favorably detect a flaw not only on a flat part of the surface of an article to be inspected but also an irregular part by vertically sliding an ultrasonic probe and by pressing the probe on the surface of the article to be inspected. CONSTITUTION:An ultrasonic probe 2 is held on a unit with a cover 4 and a holder 6, and repulsion by compression of a spring 3 provided between a spring receiver 7 and the cover 4 of the probe 2 presses the probe 2 onto an article to be inspected 1 so that it follows the irregularity of the article to be inspected 1. A supply port 1 facilitates inflow and holding by a groove 10 of a contact medium led to the neighborhood of the probe 2, a key 5 stops rotation of the probe 2 in the radial direction with combination with a key way of the holder 6 and enables vertical sliding. Also, a shoe 9 whose contact face is machined according to the piping diameter of the article to be inspected 1 facilitates mounting on the piping. Thus, the probe 2 is made into a unit, and a pressing force, inclination of the contact face and contact medium supply amount can be made as prescribed by pressing with the spring, etc., and then, ultrasonic flaw detection can be done favorably even on the irregular face of the article to be inspected 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic flaw detection mechanism,
The present invention relates to an ultrasonic probe unit suitable for ultrasonic flaw detection of not only an object having a flat surface but also an object having irregularities.

[0002]

2. Description of the Related Art Conventionally, a mechanism for pressing an ultrasonic probe against the surface of a subject is such that an ultrasonic probe driving device is provided with an air cylinder or the like as described in JP-A-62-56856. The structure was such that the tentacle holding mechanism was pressed against the subject.

Further, in order to improve the conformability of the surface shape of the subject,
As disclosed in Japanese Patent Laid-Open No. 61-84553, there is a method in which a space is provided between the shoe and the ultrasonic probe, and the contact medium is supplied from there to reduce the space of the shoe occupied by the contact medium supply hole. . This method reduces the contact area with the object by reducing the outer dimension of the shoe and improves the followability to the surface shape of the object.

Further, in the flaw detection of an object having an uneven portion, in the conventional two-division type ultrasonic probe, when flaw detection by the water gap method is performed, the sound insulation plate for blocking the transmission and reception of the ultrasonic waves is the ultrasonic wave. Since the probe is located on the surface of the probe, the distance between the probe and the surface of the probe should be a distance including the water gap and the roughness of the surface of the sample.

[0005]

In both of the above-mentioned prior art known examples, there is no problem in following a gentle curved tube shape, but since contact with the subject becomes a shoe, the contact area is reduced. Has a limit considering the strength and life of the shoe. If the unevenness is small, such as a pipe weld, and exists all around, reduce the contact area until the ultrasonic probe is brought into contact with the subject, as is done by manual flaw detection, and If the dent is not made to follow, the contact medium leaks from the circumferential direction of the pipe before accumulating between the ultrasonic probe and the subject, and the contact medium is not sufficiently retained.

Further, in flaw detection with a two-division type probe by the water gap method, a gap between the ultrasonic probe and the subject causes a leak of acoustic waves during transmission and reception, and a dead zone near the surface. Becomes

An object of the present invention is to improve the holding property of the contact medium by reducing the portion where the ultrasonic probe comes into contact with the subject, and the sound insulation plate comes into contact with the subject so that the ultrasonic wave between transmitting and receiving is improved. The purpose of this is to prevent the occurrence of a dead zone due to the leakage of sound waves, and to make it possible to detect flaws not only on the flat portion of the subject surface but also on the uneven portion.

[0008]

[Means for Solving the Problems] In the ultrasonic probe unit, a structure is provided in which the ultrasonic probe is independently slid up and down, and the ultrasonic probe has a structure that presses it against the surface of the subject. Reduce the effective contact area between the acoustic probe and the subject.

Further, by extending the sound insulating plate of the ultrasonic probe and projecting it from the surface of the ultrasonic probe, the sound insulating plate comes into contact with the object to be tested and leakage between transmission and reception is eliminated.

By these methods, the holding property of the contact medium is improved and the ultrasonic wave can be propagated well.

[0011]

[Operation] The ultrasonic probe is pressed by a spring.
This method takes into consideration the simplification and downsizing of the structure, and a method of pressing using a fluid such as air or water may be considered. By using a compression spring, the spring further contracts in the normal portion and the convex portion, and the contraction amount returns in the concave portion, so that both the irregular portion and the normal portion follow.

Further, the ultrasonic probe which slides in the vertical direction by a spring is held by making holes at the upper and lower portions of the unit and fitting the holes with the ultrasonic probe.

In the flaw detection with the two-division type probe by the water gap method, a gap is formed between the ultrasonic probe and the subject. Due to the gap, the transmitted wave bounces off the surface of the subject and enters the receiving side, and the acoustic wave leaks, which becomes noise and causes a dead zone. By extending the sound insulation plate and bringing it into contact with the subject, the gap can be eliminated and the leakage of sound waves can be prevented.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS.

In FIG. 1, the spring 3 is inserted between the spring receiver 7 attached to the ultrasonic probe 2 and the cover 4, and the repulsion due to the compression of the spring 3 is utilized to follow the unevenness of the surface of the subject 1. 1 shows a structure of a static pressure type ultrasonic probe unit having a structure in which a sound wave probe 2 is slid up and down.

In FIG. 2, the case 16 is extended from the wedge 14 and a gap is provided between the object and the wedge to enable flaw detection by the water gap method, and by extending the sound insulation plate 13, ultrasonic waves from the transmission oscillator 11 are detected. 2 shows the structure of a two-division ultrasonic probe 2 for flaw detection by the water gap method, which is designed to prevent the leakage of the light into the receiving transducer 12.

FIG. 3 is a view of the ultrasonic probe 2 as seen from below, showing the couplant inflow groove 10 provided in the case 16.

In FIG. 1, reference numeral 1 is a test object, and 2 is a two-division type ultrasonic probe used for flaw detection by the water gap method. Below, several ultrasonic probes are used so that the contact medium can be easily introduced and held. The groove 10 is processed. Ultrasonic probe 2 by spring 3
Are pressed against the subject 1. The contact medium supply port 8 is for guiding the contact medium supplied from the contact medium supply device to the vicinity of the ultrasonic probe 2. Reference numeral 9 is a shoe having a contact surface processed to match the diameter of the pipe so that it can be easily installed in the pipe of the subject. Reference numeral 5 denotes a key attached to the ultrasonic probe 2, which is combined with a key groove formed in the holder 6 to prevent the ultrasonic probe from rotating in the circumferential direction and allow the ultrasonic probe 2 to slide up and down. I am trying. The ultrasonic probe 2 is held by the unit by fitting the holes of the cover 4 and the holes of the holder 6.

According to this embodiment, the ultrasonic probe 2 comes into contact with the subject 1, and the contact area can be reduced.
It follows the irregularities on the surface of the subject 1 well and can store the couplant.

Further, it is possible to prevent the ultrasonic wave from leaking during transmission and reception and to prevent the occurrence of a dead zone due to noise.

Next, a second embodiment of the present invention will be described with reference to FIG. This example is an example relating to claim 2. In the first embodiment, the ultrasonic probe 2 is held in the hole of the cover 4 and the hole of the holder 6 and slides only up and down. However, in the second embodiment, the holder 18 has a curved surface. By attaching the ultrasonic probe 2, the ultrasonic probe 2 can be moved not only in the vertical sliding direction but also in the θ direction, and the followability to the irregularities on the surface of the subject 1 is improved.

In the present invention, the holder 18 is provided with a curved surface in consideration of the simplification and miniaturization of the structure. However, by holding the ultrasonic probe 2 in the holder 18 via a spherical bearing or the like, θ It is also possible to increase the movement in the direction and further improve the followability.

Next, a third embodiment of the present invention will be described with reference to FIG. This example is an example relating to claim 3. In the first embodiment, the cover 4 is required for holding the ultrasonic probe 2 and for the fulcrum of the compression spring 3. However, in the third embodiment, the tension spring 19 is used for the ultrasonic wave. The probe 20 is held only by the holder 21, and the tension spring 1
By attaching 9 to the ultrasonic probe 20 and the holder 21, it is possible to press against the subject 1, and the cover 4 of the first embodiment is unnecessary, and the structure of the ultrasonic probe unit is simplified.

Next, a fourth embodiment of the present invention will be described with reference to FIG. In the first embodiment, the ultrasonic probe 2 has the case 16
Also, the sound insulation plate 13 is traveled from the wedge 14 to form a water gap. In addition, it is not considered to attach it to a driving device to automate flaw detection.

In the fourth embodiment, a water gap shoe 22 is attached to the ultrasonic probe 25 so as to obtain a water gap, and the water gap shoe 22 comes into contact with the object 1 to be inspected. It is possible to prevent the wear of 25 and to provide the holder 26 with the metal fitting 23 so that the holder is attached to the drive unit 24 and the flaw detection is automated.

[0026]

According to the present invention, by unitizing the ultrasonic probe and further pressing the ultrasonic probe with a spring or the like, the pressing force, the inclination of the contact surface, and the supply amount of the contact medium are kept constant. Therefore, it is possible to improve the reproducibility of ultrasonic flaw detection of a subject having an uneven surface.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an ultrasonic probe unit according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an example of the structure of an ultrasonic probe applied to the first embodiment of the present invention.

FIG. 3 is a bottom view of a structural example of an ultrasonic probe applied to the first embodiment of the present invention.

FIG. 4 is a cross-sectional view of an ultrasonic probe unit according to a second embodiment of the present invention.

FIG. 5 is a cross-sectional view of an ultrasonic probe unit according to a third embodiment of the present invention.

FIG. 6 is a sectional view of an ultrasonic probe unit according to a fourth embodiment of the present invention.

[Explanation of symbols]

1 ... Subject, 2 ... Ultrasonic probe, 3 ... Spring, 4 ... Cover, 5 ... Key, 6 ... Holder, 7 ... Spring retainer, 8 ... Contact medium supply port, 9 ... Shoe, 10 ... Contact medium inflow Groove, 11
... Transmitting oscillator, 12 ... Receiving oscillator, 13 ... Sound insulation plate, 14
a, 14b ... Wedge, 15a, 15b ... Connector, 16 ... Case, 17a, 17b ... Transducer connector cable.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yukio Kakinuma 3-2-1, Sachimachi, Hitachi City, Ibaraki Prefecture Hitachi Engineering Co., Ltd.

Claims (4)

[Claims] 1. An ultrasonic probe unit for use in an ultrasonic flaw detector for detecting defects such as cracks generated in a subject, the ultrasonic probe unit comprising a shoe, a holder, a cover and an ultrasonic probe, which is arranged at the center. The ultrasonic probe is held by the holder and the cover so as to be slidable up and down, and the ultrasonic probe constantly presses the subject by a spring or the like. Transducer unit. 2. The curved surface of the surface of the subject as defined in claim 1, wherein a curved portion is provided at a central portion of the holder, and the ultrasonic probe is held by the curved portion. An ultrasonic probe unit in which the ultrasonic probe in the ultrasonic probe unit is tilted along and presses the subject. 3. The ultrasonic probe according to claim 1, wherein a tension spring or the like is used to press the ultrasonic probe, and the ultrasonic probe is attached between the ultrasonic probe and the holder so that the ultrasonic probe can slide up and down. The ultrasonic probe unit in which the ultrasonic probe constantly presses the subject even if the cover is not required. 4. The ultrasonic probe according to claim 1, wherein the ultrasonic probe is of a two-part type and is used in a water gap method, and a sound insulating plate for shielding between transmission and reception of ultrasonic waves is extended. Child unit.