JP3447003B2 - Local immersion probe - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a probe for local water immersion used in ultrasonic inspection for injecting ultrasonic waves to an object to be inspected and detecting defects in the object to be inspected.

[0002]

2. Description of the Related Art Generally, a welded portion of piping in a plant such as a thermal power plant is subjected to nondestructive inspection in order to evaluate its soundness. Non-destructive inspection includes radiation inspection and ultrasonic inspection, and even if the radiation inspection is currently being performed, if the accuracy of JIS Z3104 is guaranteed, this regulation may be applied to substitute for ultrasonic inspection. I also have. To do so, the thickness of the inspection object (base material) is 25 m.
In the most severe case of m or less, it is required to detect a defect having a diameter of 0.5 mm.

In order to detect such defects of the object to be inspected by ultrasonic inspection, the local water immersion method is effective. The local water immersion method fills the inside of a cylinder or a water bag with a film on the contact surface with the object to be inspected with water, and the contact medium is interposed on the contact surface with the object to be inspected to focus on the focused ultrasonic waves in water. An ultrasonic wave is made incident on an object to be inspected from a probe and the reflected wave is measured.

For example, "Welding Society Papers, Vol. 15, No. 1"
No. 58, p58-63 (1997), "Ultrasonic testing of spot welds by local water immersion method", as an ultrasonic flaw detection method for spot welds of thin plates, a water tank covered with a thin film is contacted with the surface in contact with the thin plates. A method has been proposed in which a focused ultrasonic probe is placed in a water tank filled with water through a medium, and focused ultrasonic waves are sent to a spot weld through a water-film-contact medium to cause deep scratches. .

Further, in Japanese Patent Laid-Open No. 7-218476, water is supplied from a water supply port in the upper part of a cylindrical body, and water is constantly leaked from an air vent hole located higher than the water supply port. There has been proposed a probe for local water immersion which discharges onto a material to be flaw-detected and prevents an abnormal decrease in water level in the cylinder.

[0006]

However, in the above-mentioned conventional local water immersion method, only the flat plate is inspected, and no consideration is given to the case of inspecting the entire circumference of the peripheral welded portion of the pipe. Also, in actual work, it is necessary to adjust the focal length of the probe according to the thickness of the object to be inspected, but the conventional local immersion probe has a mechanism for adjusting the focal length. Absent.

Therefore, when the object to be inspected is a pipe, the surface is a curved surface, so that it is difficult to perform ultrasonic inspection by the local water immersion method, and the pipes having different wall thicknesses have different focal lengths. It is necessary to prepare a tentacle and perform an inspection.

An object of the present invention is to provide a probe for local immersion in which ultrasonic waves can be satisfactorily incident on the object to be inspected even if the surface shape of the object to be inspected is a curved surface, and the focal length can be easily adjusted. To provide.

[0009]

According to a first aspect of the present invention, there is provided a local water immersion probe having a tubular shape, wherein one opening is closed with a film and a lid is provided at the other opening to store a liquid inside. A filled holder, a focusing ultrasonic probe which is housed in the holder and injects ultrasonic waves into the object to be inspected through the film, and the focusing ultrasonic probe is penetrated and held in a central portion of the holder. E
Along the inner surface of Ruda front moves in the axial direction of the holder
A probe moving part for adjusting the focal length of the recording-focusing ultrasonic probe is provided.

In the probe for local water immersion according to the first aspect of the invention, one opening of the cylindrical holder is closed with a film and the other opening is covered with a liquid to fill the inside. And seal the focused ultrasonic probe. The focused ultrasonic probe causes ultrasonic waves to enter the object to be inspected through the film. At that time, the focused ultrasonic probe is moved to the center by the movable part of the probe.
The lens is penetrated and held, and is moved along the inner surface of the holder in the axial direction of the holder to adjust the focal length. Therefore, it is possible to prevent bubbles from entering from the outside of the holder, and the liquid is constantly filled in the holder, so that good flaw detection can be performed in any posture. In addition, the holder is formed into a cylindrical shape, and the focused ultrasonic probe is used.
Hold the movable part of the probe that holds the probe through the center.
Since it moves along the inner surface of the dar, it can be focused in the holder.
The ultrasonic probe can be moved stably and uniformly.

According to a second aspect of the present invention, there is provided a probe for local immersion in the first aspect of the present invention, wherein the movable part of the probe is held by penetrating the focused ultrasonic probe into a central portion thereof. that was
A slide member whose outer peripheral surface slides along the inner surface of the holder and is movable in the axial direction of the holder, and a slide member which is provided slidably on the outer peripheral surface of the holder in the axial direction of the holder by magnetic force. It is characterized by having a movable holder for moving.

In the probe for local immersion according to the invention of claim 2, in addition to the action of the invention of claim 1, the focused ultrasonic probe is a slide part which is movable in the holder in the axial direction.
It is held by being penetrated through the center by the material, and the slide member
The outer peripheral surface slides along the inner surface of the holder. When adjusting the focal length, the slide member in the holder is moved in the axial direction by the magnetic force according to the movement of the outer peripheral surface of the holder in the axial direction of the movable holder.

According to a third aspect of the present invention, there is provided a probe for local immersion in the first aspect of the present invention, wherein the movable part of the probe is held by penetrating the focused ultrasonic probe in a central portion thereof. The slide member movable in the axial direction of the holder is divided into the holder, and the inner surface of the holder is the slide member.
A rotary unit holder screwed with the outer peripheral surface of the rotary member to move the slide member in the axial direction of the holder by a rotational force ;
When the rotating part holder installed in the holder rotates
Linearly move the slide member in the axial direction of the holder.
And a guide member for guiding .

In the probe for local water immersion according to the third aspect of the invention, in addition to the action of the first aspect of the invention, the focused ultrasonic probe is provided with a slide member that is axially movable in the holder. held by penetrating the center of the rotation holder by rotating the rotating unit holder when adjusting the focal length
Applying rotational force to the outer peripheral surface of the slide member that is screwed with the inner surface,
The guide member converts the rotational force into a linear driving force in the axial direction to move the slide member in the holder in the axial direction. Therefore, the slide member does not rotate and the guide portion
Guided by the material, the focal length can be adjusted smoothly.

According to a fourth aspect of the present invention, there is provided a probe for local water immersion in the second or third aspect of the invention, wherein the slide member is adapted to move liquid that is pushed out from one space inside the holder as the slide member moves. It is characterized by having a liquid flow passage for guiding to the other space.

In the probe for local water immersion according to the invention of claim 4, in addition to the effect of the invention of claim 2 or 3, the holder is moved along with the movement of the slide member when adjusting the focal length. The liquid extruded from one of the inner spaces is guided to the other space through the liquid flow passage. As a result, the volume inside the holder does not change and the inside of the holder can be kept in a sealed state.

According to a fifth aspect of the present invention, in the probe for local water immersion according to the second aspect of the present invention, the slide member is guided by a guide member provided in the holder so as to extend in the axial direction of the holder. It is characterized by moving in a straight line.

According to the probe for local water immersion of the fifth aspect of the present invention, in addition to the function of the second aspect of the invention , when the focal length is adjusted, the slide member is placed inside the holder from outside the movable holder . Apply axial force. As a result, the slide member is guided and moved by the guide member linearly provided in the axial direction in the holder by the magnetic force . Therefore, the slide member does not rotate, and the focal length can be adjusted smoothly.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. FIG. 1 is a sectional view of a probe for local water immersion according to a first embodiment of the present invention.

A focusing type ultrasonic probe 11 for injecting ultrasonic waves to the object to be inspected is housed in a holder 12. The holder 12 is formed in a cylindrical shape, one opening is covered with a film 13, and the other opening is provided with a lid 14.
For example, it is filled with water or oil. The membrane 13 is fixed to the tip of the holder 12 by a circle 23. The lid 14 has a rubber packing 25 on the rear end of the holder 12.
It is fixed by a screw 26 through. Microdots 27 are provided on the lid 14 and are connected to the coaxial connector 28 of the focused ultrasonic probe 11.

As described above, the focused ultrasonic probe 11 is
The membrane 13 is attached to the front end portion, and the lid 14 is fixed to the rear end portion via the rubber packing 25 together with the liquid in the holder 12 fixed. Then, ultrasonic waves are incident on the object to be inspected through the film 13. The focused ultrasonic probe 11 is held in the holder 12 by the slide member 15. The slide member 11 is configured to be movable in the holder 12 in the axial direction, and moves in the axial direction when adjusting the focal length.

FIG. 2 is an explanatory view of the slide member 15.
2A is a front view and FIG. 2B is a side view. The slide member 15 is formed in a cylindrical shape, and a through hole 16 for holding the focused ultrasonic probe 11 is provided in the center thereof. The focused ultrasonic probe 11 inserted into the through hole 16 is
It is fixed to the slide member 15 by a screw passed through the screw hole 17.

The slide member 15 has a liquid flow passage 1
9 is provided, and the slide member 1 is provided for adjusting the focal length.
When 5 is moved in the axial direction of the holder 12, the liquid flow passage 19 guides the liquid pushed out from one space inside the holder 12 to the other space.

Thus, the focused ultrasonic probe 11 is
It is inserted into the through hole 16 of the slide member 15 shown in FIG. 2 and the screw 18 is passed through the screw hole 17 to be fixed to the slide member 15. The head of the screw 18 is slidably engaged with the guide member 20 formed inside the holder 12. As a result, the slide member 15 is guided by the guide member 20 and is movable in the axial direction of the holder 12. Note that FIG. 1 shows the case where the guide member 20 is a slit provided in the holder 12.

Next, a movable holder 21 for moving the slide member 15 housed in the holder 12 is provided on the outer peripheral surface of the holder 12. The movable holder 21 is slidably provided on the outer peripheral surface of the holder 12 and includes a magnet 22. The slide member 15 is made of ferromagnetic material such as iron, and the magnetic force of this magnet 22 moves the slide member 15 in the holder 12.

That is, the slide member 15 and the movable holder 21 constitute a probe movable portion for adjusting the focal length, and the focused ultrasonic probe 11 is held by the probe movable portion. It is movable in 12 axial directions. The movable holder 21 is provided with a screw 24, and after adjusting the focal length, the movable holder 21 is fixed to the holder 12 by the screw 24.

When adjusting the focal length, the screw 24 fixing the movable holder 21 is loosened to move the movable holder 21 in the axial direction. Then, the magnetic force of the magnet 22 of the movable holder 21 causes the iron slide member 15 to move together with the focusing ultrasonic probe 11.

At this time, the screw 18 for fixing the focusing ultrasonic probe 11 to the slide member 15 moves along the slit (guide member 20) formed in the inner surface of the holder 12 in the axial direction. The ultrasonic probe 11 is moved in the axial direction without rotating. The liquid pushed out from one space at the time of movement of the focused ultrasonic probe 11 flows out to the other space through the liquid flow passage 19 formed in the slide member 15. Then, after adjusting the focal length, the focusing ultrasonic probe 11 is fixed by tightening the screw 24 of the movable holder 21.

As described above, according to the first embodiment, the liquid is sealed in the holder 12, so that the ultrasonic waves from the focused ultrasonic probe can always propagate through the liquid. . Therefore, even if the shape of the object to be inspected is a curved surface, good flaw detection can be performed in any posture. Further, since the focused ultrasonic probe 11 inside the holder 12 can be moved by magnetic force only by moving the movable holder 21, the focal length can be easily adjusted, and proper flaw detection can be performed according to the thickness of the object to be inspected. It will be possible.

Next, a second embodiment of the present invention will be described. FIG. 3 is a sectional view of a probe for local water immersion according to a second embodiment of the present invention. The second embodiment is different from the first embodiment shown in FIG. 1 in that the holder 12 is divided into a fixed portion holder 12a and a rotary portion holder 12b, and the probe movable portion is a rotary portion holder 12b. And the slide member 15. That is, the slide member 15 holding the focused ultrasonic probe 11 can be moved in the axial direction of the fixed portion holder 12a by the rotational force of the rotating portion holder 12b. Hereinafter, the same elements as those of the first embodiment will be designated by the same reference numerals, and overlapping description will be omitted.

In FIG. 3, the fixed portion holder 12a and the rotating portion holder 12b are formed in a tubular shape, and the fixed portion holder 12a and the rotating portion holder 12b are connected so as to be an outer cylinder and an inner cylinder, respectively. Then, a rubber packing 29 is provided on the coupling surface, liquid is filled in the fixed portion holder 12a and the rotating portion holder 12b, and the focused ultrasonic probe held by the slide member 15 by the screw 18. 11 is stored. The rubber packing 29 prevents water leakage and air bubbles from the fixed holder 12a and the rotating portion holder 12b. Fixed part holder 1
A holder tightening ring 37 is provided at a connecting portion between the 2a and the rotating portion holder 12b.

A female screw 38 is formed on the inner surface of the rotating portion holder 12b, and is screwed with a male screw 30 formed on the outer peripheral surface of the slide member 15 to be described later to adjust the focal length. The slide member 15 can be moved within the fixed portion holder 12a when the rotating portion holder 12b is rotated.

FIG. 4 is an explanatory view of the slide member 15,
FIG. 4A is a front view and FIG. 4B is a plan view. The slide member 15 is formed in a cylindrical shape, and a through hole 16 for holding the focused ultrasonic probe 11 is provided in the center thereof. The focused ultrasonic probe 11 inserted into the through hole 16 is
It is fixed to the slide member 15 by a screw passed through the screw hole 17.

A liquid flow passage 19 is provided in the slide member 15, and when the slide member 15 is moved in the axial direction of the holders 12a and 12b for adjusting the focal length, the liquid flow passage 19 allows the holder 12a to move. , 12b, the liquid pushed out from one space is guided to the other space. Further, on the outer peripheral surface of the slide member 15,
A male screw 30 that is screwed into a female screw formed on the inner surface of the rotating portion holder 12b is formed.

As described above, the focused ultrasonic probe 11 is
The slide member 15 shown in FIG. 4 is inserted into the through hole 16 and the screw 18 is inserted into the screw hole 17 to be fixed to the slide member 15. Then, the male screw 30 on the outer peripheral surface of the slide member 15 and the female screw on the inner surface of the fixed portion holder 12b are screwed together and housed in the fixed portion holder 12a.

A rotation prevention collar 31 is attached to the focusing ultrasonic probe 11 with a screw 32.
The head is slidably engaged with a guide member 20 formed inside the fixed portion holder 12a. As a result, the slide member 15 is guided by the guide member 20 and the fixed portion holder 1
It is linearly movable in the axial direction of 2a.

FIG. 5 is an explanatory view of the rotation preventing collar 31, FIG. 5 (a) is a front view, FIG. 5 (b) is a side view, and FIG.
(C) is a plan view. The rotation prevention collar 31 has a screw hole 33 through which a screw 32 for fixing to the focused ultrasonic probe 11 is inserted.
And a convex portion 34 that is in contact with the slide member 15.
have.

FIG. 6 is an explanatory view of the guide member 20, FIG. 6 (a) is a front view, and FIG. 5 (b) is a plan view. The guide member 20 is provided with a screw hole 35 through which a screw for fixing to the fixed portion holder 12a is inserted, and a slit 36 which engages with the screw 32 of the rotation preventing collar 31 and guides in the axial direction of the fixed portion holder 12a. ing.

When the focal length is adjusted, the holder tightening ring 37 is loosened and the rotating portion holder 12b is rotated to move the focusing ultrasonic probe 11 together with the slide member 15. At this time, the screw 32 fixing the anti-rotation collar 31 moves along the slit 36 formed in the guide member 20 in the axial direction.
Moves axially without rotating.

The liquid extruded from one space when the focused ultrasonic probe 11 is moved is divided into the liquid flow passage 19 formed in the slide member 15, the rotation preventing collar 31, and the guide member 20. It flows into the other space through the gap. After adjusting the focal length, the focusing ultrasonic probe 11 can be fixed by tightening the holder tightening ring 37.

As described above, according to the second embodiment, since the liquid is sealed in the holder 12, the ultrasonic waves from the focused ultrasonic probe can always propagate through the liquid. . Therefore, even if the shape of the object to be inspected is a curved surface, good flaw detection can be performed in any posture. Further, since the focused ultrasonic probe 11 inside the fixed holder 12a can be moved only by rotating the rotating portion holder 12b, the focal length can be easily adjusted, and the flaw detection can be performed appropriately according to the thickness of the object to be inspected. Is possible.

[0042]

As described above, according to the present invention, since the focusing ultrasonic probe is sealed inside the holder together with the liquid, the ultrasonic wave from the focusing ultrasonic probe is always liquid. Can propagate through. Therefore, even if the shape of the object to be inspected is a curved surface, good flaw detection can be performed in any posture. In addition, since the focusing ultrasonic probe can be indirectly moved from the outside in the axial direction to adjust the focal length, appropriate flaw detection can be performed according to the thickness of the object to be inspected.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a local immersion probe according to a first embodiment of the present invention.

2A and 2B are explanatory views of a slide member according to the first embodiment of the present invention, FIG. 2A is a front view, and FIG. 2B is a side view.

FIG. 3 is a sectional view of a probe for local water immersion according to a second embodiment of the present invention.

FIG. 4 is an explanatory view of a slide member according to a second embodiment of the present invention, FIG. 4 (a) is a front view and FIG. 4 (b) is a plan view.

5A and 5B are explanatory views of a rotation preventing collar according to the second embodiment of the present invention, FIG. 5A is a front view, and FIG.
Is a side view and FIG. 5C is a plan view.

6A and 6B are explanatory views of a guide member according to a second embodiment of the present invention, FIG. 6A is a front view, and FIG. 5B is a plan view.

[Explanation of symbols]

11 ... Focusing type ultrasonic probe, 12 ... Holder, 12a ...
Fixed part holder, 12b ... Rotating part holder, 13 ... Membrane,
14 ... Lid, 15 ... Slide member, 16 ... Through hole, 17 ...
Screw hole, 18 ... Screw, 19 ... Liquid flow passage, 20 ... Guide member, 21 ... Movable holder, 22 ... Magnet, 23 ... ○ ring, 24 ... Screw, 25 ... Rubber packing, 26 ... Screw, 2
7 ... Microdot, 28 ... Coaxial connector, 29 ... Rubber packing, 30 ... Male screw, 31 ... Rotation prevention collar, 3
2 ... screw, 33 ... screw hole, 34 ... convex portion, 35 ... screw hole,
36 ... Slit, 37 ... Holder tightening ring, 38 ... Female screw

─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-8-280680 (JP, A) JP-A-63-307354 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G01N 29/00-29/28 A61B 8/00-8/15

Claims (5)

(57) [Claims] 1. A holder, which is formed in a tubular shape and has one opening closed with a film and a lid provided in the other opening, and filled with a liquid inside, and an ultrasonic wave which is housed in the holder and passed through the film to an object to be inspected. And a holder for holding the focused ultrasonic probe by penetrating the central part of the focused ultrasonic probe.
Along the inner surface moving said focused in the axial direction of the holder
A probe for local water immersion, comprising: a movable part of the probe for adjusting the focal length of the ultrasonic probe . 2. The movable part of the probe has the focused ultrasonic probe penetrated through a central part thereof to be held, and an outer peripheral surface of the focused ultrasonic probe is retained by the probe movable part.
A slide member that slides along the inner surface of the rudder and is movable in the axial direction of the holder, and a movable holder that is slidably provided on the outer peripheral surface of the holder and that moves the slide member in the axial direction of the holder by magnetic force. The probe for local water immersion according to claim 1, further comprising: 3. The probe movable portion is provided by dividing the holder and a slide member that holds the focused ultrasonic probe through the central portion thereof and is movable in the axial direction of the holder. And its inner surface is screwed onto the outer peripheral surface of the slide member.
And a rotation part holder for moving the slide member in the axial direction of the holder by a rotation force , and
When the rotating part holder is rotated, the slide
A guide part for linearly guiding the member in the axial direction of the holder
The local immersion probe according to claim 1, further comprising a material . 4. The liquid flow passage according to claim 2, wherein the slide member has a liquid flow passage for guiding the liquid pushed out from one space in the holder to the other space as the slide member moves. The local immersion probe described. 5. The local immersion probe according to claim 2, wherein the slide member is guided by a guide member provided in the holder and linearly moves in the axial direction of the holder. Tentacles.