JP2024106662A - Apparatus and method for measuring internal structure of cylindrical structure, and inspection apparatus for cooling water piping in nuclear fusion device - Google Patents

Abstract

To provide an internal structure measurement device of a cylindrical structure and an internal structure measurement method of the cylindrical structure which can acquire information about an internal structure of the cylindrical structure in a non-immersion manner without increasing the complexity or size of the device.SOLUTION: An internal structure measurement device of a cylindrical structure includes: an ultrasonic probe which is introduced into a space in the cylindrical structure; a support body which supports the ultrasonic probe; and a drive mechanism which moves the support body in a radial direction of the cylindrical structure. The drive mechanism is provided outside the cylindrical structure. An internal structure measurement method of the cylindrical structure is also provided. According to this invention, the adhesion between the ultrasonic probe and an inspected site is improved when bringing the ultrasonic probe into contact with the inspected site of the cylindrical structure, and measurement based on the ultrasonic flaw detection in a non-immersion manner can be performed stably. In addition, by installing the drive mechanism outside the cylindrical structure, the structure introduced into the cylindrical structure can be miniaturized, and measurement can be performed for the cylindrical structure with a small diameter.SELECTED DRAWING: Figure 5

Description

The present invention relates to an apparatus and method for measuring the internal structure of a tubular structure.
The present invention also relates to an inspection device for cooling water piping in a nuclear fusion device equipped with an internal structure measuring device for a tubular structure.

When inspecting and maintaining tubular structures, particularly piping, various inspections are carried out to obtain information on the internal and external structures of the tubular structures (piping). In particular, because workers cannot visually inspect the internal structure of tubular structures (piping), inspections to obtain information on the internal structure are important.

As an inspection for obtaining information on the internal structure of a cylindrical structure, a non-destructive inspection using ultrasonic waves (ultrasonic flaw detection) is widely used.
Ultrasonic inspection is widely used to inspect the outer wall of a tubular structure, but there are cases where there is another structure on the outer wall of the tubular structure, or where it is difficult to install an inspection device due to its relative position to other structures.

On the other hand, ultrasonic inspection is also known to inspect the inside wall of a cylindrical structure. Since ultrasonic waves have the property of not propagating through gas (air), when inspecting the inside wall of a cylindrical structure using ultrasonic inspection, it is common to use the immersion method, in which the area to be inspected (the space inside the cylindrical structure) is submerged in water.

For example, Patent Document 1 describes an ultrasonic flaw detection device that is inserted into a small-diameter test pipe, and includes a turbine supported within a cylindrical casing so that it can rotate freely due to the flow of liquid inside the pipe, an acoustic mirror, a liquid cutting tool that increases the liquid flow rate, and an ultrasonic probe. It describes how ultrasonic flaw detection is performed by utilizing the water flow inside the test pipe, with the acoustic mirror rotating by the turbine reflecting ultrasonic waves, and propagating the ultrasonic waves in a helical manner around the entire circumference of the pipe.

Japanese Patent Application Publication No. 3-087653

The ultrasonic flaw detection device described in Patent Document 1 is a submersible type, and since the flaw detection device is moved using the water flow (water pressure) inside the pipe, it is necessary to submerge the entire length of the pipe to be inspected, not just the part to be inspected. For this reason, depending on the structure (total length) of the cylindrical structure, large-scale equipment (water pump, water separation tank, etc.) may be required to submerge the pipe, which can be costly to apply, or it may not be applicable to objects that are difficult to submerge in water.

One example of a solution to this problem is to perform ultrasonic testing without immersion, but the drive mechanisms of conventional non-immersion ultrasonic testing equipment tend to be complex and large, making it difficult to apply to small-diameter tubular structures. In particular, there is little working space or time available for inspection, such as the cooling water piping in nuclear fusion devices, and it has been difficult to perform proper inspection of small-diameter tubular structures.

The objective of the present invention is to provide an internal structure measurement device and method for measuring the internal structure of a tubular structure that can obtain information about the internal structure of a tubular structure in a non-submersible manner without complicating or increasing the size of the device, and to provide an inspection device for cooling water piping in a nuclear fusion device that can perform appropriate inspection even under harsh working conditions.

As a result of thorough investigation into the above-mentioned problems, the inventors have come to the discovery that when measuring the internal structure of a tubular structure, measurements are performed based on ultrasonic testing, and when an ultrasonic probe is introduced into the space inside the tubular structure, a support is used to support the ultrasonic probe, and an operating part (driving part) for moving (driving) this support is provided outside the tubular structure, which makes it possible to obtain information about the internal structure of a tubular structure in a non-submersible manner without making the device more complicated or larger, and thus completed the present invention.
That is, the present invention provides the following internal structure measuring device for a tubular structure, internal structure measuring method for a tubular structure, and inspection device for cooling water piping in a nuclear fusion device.

In order to solve the above problems, the internal structure measuring device of the present invention for a tubular structure comprises an ultrasonic probe that is introduced into the space within the tubular structure, a support that supports the ultrasonic probe, and a driving mechanism that moves the support in the radial direction of the tubular structure, wherein the driving mechanism is provided outside the tubular structure.
According to this feature, the ultrasonic probe is introduced into the space inside the cylindrical structure while being supported by a support, and the support is moved in the radial direction of the cylindrical structure by a driving mechanism, thereby enabling measurement based on ultrasonic inspection by bringing the ultrasonic probe close to and into contact with the inspection site of the cylindrical structure. At this time, by providing the driving mechanism outside the cylindrical structure, it is mainly the ultrasonic probe and the support, which are easily miniaturized, that are introduced into the cylindrical structure. This makes it possible to perform measurement based on ultrasonic inspection from the inner wall side of a small-diameter cylindrical structure.
Furthermore, according to this feature, the ultrasonic probe moves in the radial direction of the cylindrical structure via the support, so that when the ultrasonic probe approaches or comes into contact with the inspection site of the cylindrical structure, the ultrasonic probe receives a force from the support along the radial direction of the cylindrical structure (a force pressing the ultrasonic probe toward the inspection site). This improves the adhesion between the ultrasonic probe and the inspection site, making it possible to stably perform measurements based on non-immersion ultrasonic testing.

In addition, in one embodiment of the internal structure measuring device for a cylindrical structure of the present invention, the driving mechanism is characterized by having an XY stage that translates the support in the radial direction of the cylindrical structure, and a tilting mechanism that tilts the support in the radial direction of the cylindrical structure.
According to this feature, when moving the support (and ultrasonic probe) in the radial direction of the cylindrical structure, by providing both a mechanism for moving parallel to the radial direction of the cylindrical structure and a mechanism for tilting it, it is possible to further improve the adhesion between the cylindrical structure and the ultrasonic probe. This makes it possible to perform measurements based on non-immersion ultrasonic flaw detection more stably.

In one embodiment of the device for measuring the internal structure of a cylindrical structure according to the present invention, the ultrasonic probe is characterized in that the direction of ultrasonic emission is two-dimensional.
According to this feature, the ultrasonic probe emits ultrasonic waves in two dimensions (multiple directions), so that ultrasonic waves can be emitted over a wide area to the part to be inspected during measurement, and the reflected waves are received over a wide area as echoes, so that it is possible to quickly and easily perform measurement (flaw detection) of the part to be inspected consisting of a certain range. This makes it possible to increase the usefulness and accuracy of the information that can be obtained as information related to the internal structure of the cylindrical structure.

Moreover, one embodiment of the apparatus for measuring the internal structure of a tubular structure according to the present invention is characterized in that a contact medium is supplied between a site to be inspected on the inner wall of the tubular structure and the ultrasonic probe.
According to this feature, it becomes possible to use a contact medium as a means for further improving the adhesion between the cylindrical structure and the ultrasonic probe. Also, instead of constantly immersing the area to be inspected in water, it becomes possible to use the contact medium only when necessary (during measurement) or at the necessary location. This enables rapid and highly accurate measurement when acquiring information on the internal structure from the inner wall side of the cylindrical structure, and also makes it possible to expand the range of applicable measurement targets (cylindrical structures).

In order to solve the above-mentioned problems, the method for measuring the internal structure of a tubular structure of the present invention comprises an introduction step of introducing an ultrasonic probe supported by a support into a space within the tubular structure, and a driving step of moving the support in the radial direction of the tubular structure, and is characterized in that the driving step is performed by a driving mechanism provided outside the tubular structure.
According to this feature, the ultrasonic probe supported by the support is introduced into the space inside the cylindrical structure, and the support is moved in the radial direction of the cylindrical structure, thereby enabling measurement based on ultrasonic inspection by bringing the ultrasonic probe close to and into contact with the inspection site of the cylindrical structure. At this time, by providing the driving mechanism outside the cylindrical structure, it is mainly the ultrasonic probe and the support, which are easily miniaturized, that are introduced into the cylindrical structure. This makes it possible to perform measurement based on ultrasonic inspection from the inner wall side of a small-diameter cylindrical structure.
Furthermore, according to this feature, the ultrasonic probe moves in the radial direction of the cylindrical structure via the support, so that when the ultrasonic probe approaches or comes into contact with the inspection site of the cylindrical structure, the ultrasonic probe receives a force from the support along the radial direction of the cylindrical structure (a force pressing the ultrasonic probe toward the inspection site). This improves the adhesion between the ultrasonic probe and the inspection site, making it possible to stably perform measurements based on non-immersion ultrasonic testing.

In order to solve the above problems, the present invention provides an inspection device for cooling water piping in a nuclear fusion device, which is characterized by including the above-mentioned internal structure measuring device for a tubular structure.
In general, a nuclear fusion device is equipped with a doughnut-shaped vacuum vessel for performing nuclear fusion, and various devices (vacuum vessel internal devices) are provided inside the vacuum vessel, and the vacuum vessel internal devices are basically water-cooled. However, when inspecting the cooling water piping used for water cooling, it is difficult to secure the working space and time, in addition to the cooling water piping having a small diameter.
On the other hand, according to this feature, by using the above-mentioned internal structure measuring device for a tubular structure, it is possible to stably perform measurements based on non-immersion ultrasonic flaw detection on a small-diameter tubular structure without making the device complicated or large. In other words, it is possible to perform appropriate inspection of the cooling water piping even under severe working conditions for the inspection of the cooling water piping in a nuclear fusion device.

The present invention provides an internal structure measurement device and method for measuring the internal structure of a cylindrical structure that can obtain information about the internal structure of a cylindrical structure in a non-submersible manner without complicating or increasing the size of the device, and also provides an inspection device for cooling water piping in a nuclear fusion device that can perform appropriate inspection even under harsh working conditions.

1 is a schematic explanatory diagram showing the structure of an internal structure measuring device for a cylindrical structure according to a first embodiment of the present invention; 1 is a schematic explanatory diagram showing another aspect of the internal structure measuring device for a cylindrical structure according to the first embodiment of the present invention. FIG. 1 is a schematic explanatory diagram showing the structure of an ultrasonic probe in an internal structure measuring device for a cylindrical structure according to a first embodiment of the present invention; 1 is a schematic explanatory diagram showing the structure of a drive mechanism (tilt mechanism) in an apparatus for measuring the internal structure of a cylindrical structure according to a first embodiment of the present invention; FIG. FIG. 11 is a schematic explanatory diagram showing the structure of an internal structure measuring device for a cylindrical structure according to a second embodiment of the present invention. FIG. 11 is a schematic explanatory diagram showing the structure of an internal structure measuring device for a cylindrical structure according to a third embodiment of the present invention. FIG. 13 is a schematic explanatory diagram showing the structure of an internal structure measuring device for a cylindrical structure according to a fourth embodiment of the present invention.

Hereinafter, embodiments of the internal structure measuring device for a tubular structure, the internal structure measuring method for a tubular structure, and the inspection device for a cooling water pipe in a nuclear fusion device of the present invention will be described in detail with reference to the drawings. The internal structure measuring method for a tubular structure of the present invention will be replaced with a description of the operation of the internal structure measuring device for a tubular structure of the present invention.
It should be noted that the internal structure measuring device for a tubular structure, the internal structure measuring method for a tubular structure, and the inspection device for cooling water piping in a nuclear fusion device described in the embodiments are merely examples used to explain the present invention, and are not limited thereto.

The internal structure measuring device of the present invention for a tubular structure is a measuring device that obtains (measures) information related to the internal structure of a tubular structure from the inner wall side of the tubular structure, and performs non-immersible ultrasonic flaw detection.
Here, information related to the internal structure of a tubular structure obtained by the device for measuring the internal structure of a tubular structure of the present invention includes the presence or absence of internal damaged areas of the tubular structure, the presence or absence of internal defects in welds in the tubular structure, the wall thickness (thinning) of the tubular structure, etc. In particular, the device for measuring the internal structure of a tubular structure of the present invention makes it possible to obtain highly accurate information on the presence or absence of internal defects in welds in small-diameter tubular structures, which was difficult to obtain by conventional non-immersion ultrasonic flaw detection.

The cylindrical structure to be measured by the device for measuring the internal structure of a cylindrical structure of the present invention may be one that has a substantially circular cross section and has a space on the inner wall side, and is not particularly limited as to whether it has a bottom or not. In addition, there is no particular limitation on the material.
In the present invention, a particularly suitable cylindrical structure to be measured is a cylindrical structure (pipe) with a small diameter (200 mm or less, more preferably 100 mm or less). It is also possible to measure a cylindrical structure having a structure that makes it difficult to submerge the entire length in water. Specific examples of cylindrical structures in the present invention include, for example, heat exchangers and small diameter pipes (cooling water pipes) used in equipment inside a vacuum vessel in a nuclear fusion device.

[First embodiment]
Fig. 1 is a schematic explanatory diagram showing the structure of the internal structure measuring device for a cylindrical structure according to the first embodiment of the present invention, and Fig. 2 is a schematic explanatory diagram showing another aspect of the internal structure measuring device for a cylindrical structure according to the first embodiment of the present invention.
1(A) and 2(A) are side views, and FIGS. 1(B) and 2(B) are plan views of the II cross sections in FIGS. 1(A) and 2(A) seen from above, respectively.

1 and 2, the internal structure measuring device for a cylindrical structure in this embodiment (hereinafter simply referred to as "measuring device 1A") includes an ultrasonic probe 10 introduced into a space inside a cylindrical structure P, a support 20 supporting the ultrasonic probe 10, and a drive mechanism 30 for moving the support 20 in the radial direction of the cylindrical structure P. The measuring device 1A also includes an elevation drive mechanism 40 for raising and lowering the support 20 along the central axis direction of the cylindrical structure P, and a rotation drive mechanism 50 for rotating the support 20 in the circumferential direction of the cylindrical structure P.
1 shows a driving mechanism 30 equipped with an XY stage 31, and FIG. 2 shows a driving mechanism 30 equipped with a tilting mechanism 32. As shown in FIG.

The specific structure of the cylindrical structure P and the location of the inspection region T in this embodiment are not particularly limited.
In the following description, the tubular structure P in this embodiment is a small diameter pipe having a weld W, and the area T to be inspected by the measuring device 1A in this embodiment is a predetermined range including the weld W of the tubular structure P and its vicinity.

In this embodiment, the measuring device 1A introduces an ultrasonic probe 10 supported by a support 20 into the space inside a tubular structure P, and moves the support 20 in the radial direction of the tubular structure P using a driving mechanism 30, thereby bringing the ultrasonic probe 10 into close contact with the inspection area T of the tubular structure P.
Here, by providing the driving mechanism 30 outside the cylindrical structure P, it is mainly the ultrasonic probe 10 and the support 20 that are introduced into the cylindrical structure P. As described later, the ultrasonic probe 10 and the support 20 can be easily miniaturized, and the measuring device 1A of this embodiment can perform measurement based on ultrasonic flaw detection from the inner wall side of the cylindrical structure P having a small diameter.
Furthermore, since the ultrasonic probe 10 moves in the radial direction of the tubular structure P via the support 20, when the ultrasonic probe 10 approaches or comes into contact with the inspection area T of the tubular structure P, the ultrasonic probe 10 receives a force from the support 20 along the radial direction of the tubular structure P (a force pressing the ultrasonic probe 10 toward the inspection area T). This improves the adhesion between the ultrasonic probe 10 and the inspection area T, making it possible to stably perform measurements based on non-immersion ultrasonic flaw detection.

The components of the measuring device 1A are described below with reference to Figures 1 and 2. Note that the measuring device 1A of this embodiment shown in Figures 1 and 2 measures the internal structure of a cylindrical structure P that is erected in the vertical direction (Z direction), and in the figures, the radial direction of the cylindrical structure P refers to the horizontal direction (X direction or Y direction).

The ultrasonic probe 10 is capable of acquiring information on the internal structure of the tubular structure P (inspection area T) by transmitting and receiving ultrasonic waves. More specifically, ultrasonic waves (ultrasonic pulses) are transmitted from the ultrasonic probe 10 to the inspection area T, and the transmitted ultrasonic waves are reflected (echoes) according to the internal structure by the ultrasonic probe 10, and information on the internal structure of the inspection area T is obtained by performing calculations on the received echoes.

As the ultrasonic probe 10 in this embodiment, an ultrasonic probe generally used in ultrasonic flaw detection can be used. As the ultrasonic probe 10 in this embodiment, one having a flat transducer (piezoelectric element) capable of transmitting and receiving ultrasonic waves can be used. In addition, the arrangement direction of the transducer in the ultrasonic probe 10 is not particularly limited, and a so-called vertical probe or an angle probe can be used.
Here, when a vertical probe is used as the ultrasonic probe 10, the information obtained regarding the internal structure of the tubular structure P is mainly information regarding the wall thickness of the tubular structure P. On the other hand, when an oblique probe is used as the ultrasonic probe 10, the information obtained regarding the internal structure of the tubular structure P is mainly information regarding internal defects in the tubular structure P.
In the measuring device 1A of this embodiment, it is preferable to use an angle beam probe as the ultrasonic probe 10. This makes it possible to obtain with high accuracy information about internal defects in the welded portion W, which has been difficult to obtain using conventional non-immersion ultrasonic testing.

As the ultrasonic probe 10 in this embodiment, it is particularly preferable to use one in which the direction of ultrasonic emission is two-dimensional. More specifically, it is preferable to use one having a structure known as a phased array type as the ultrasonic probe 10. By making the direction of ultrasonic emission from the ultrasonic probe 10 two-dimensional (multiple directions), ultrasonic waves can be emitted over a wide area to the inspection area T during measurement, and the reflected waves as echoes are also received over a wide area, making it possible to quickly and easily perform measurement (flaw detection) of the inspection area T consisting of a certain range. This makes it possible to increase the usefulness and accuracy of the information that can be obtained as information related to the internal structure of the cylindrical structure P.

Figure 3 is a schematic diagram showing the structure of the ultrasonic probe 10 and the internal structure measurement in this embodiment. Note that in Figure 3, the orientation of the cylindrical structure P is rotated 90 degrees from that in Figures 1 and 2, and in the figure, the radial direction of the cylindrical structure P is the perpendicular direction (X direction).

As shown in FIG. 3, the ultrasonic probe 10 of this embodiment includes a transducer 11 and a wedge 12. Note that the ultrasonic probe 10 shown in FIG. 3 has a so-called angle probe structure.

The transducer 11 is for transmitting and receiving ultrasonic waves, and is provided with an oscillator 11a that serves as an ultrasonic transmitter and receiver at the interface with the wedge 12. In this case, it is preferable that the oscillator 11a has a phased array structure in which a single oscillator is divided into strips (segments) with sides of approximately 0.5 mm to 2.5 mm and multiple segments are arranged.

The wedge 12, as the ultrasonic probe 10, comes into contact with the cylindrical structure P and serves to improve the adhesion between the cylindrical structure P and the inspection area T. As described above, ultrasonic waves do not easily propagate through air (gas). Therefore, in order to efficiently cause the ultrasonic waves emitted from the transducer 11 to enter the inspection area T, a means for further improving the adhesion between the wedge 12 and the inspection area T may be provided. For example, as shown in FIG. 3, it is preferable to use a contact medium M between the wedge 12 and the inspection area T.
Here, the ultrasonic probe 10 of this embodiment is rotated while in contact with the inspection area T when performing measurements in the circumferential direction of the cylindrical structure P. For this reason, if the transducer 11 (oscillator 11a) and the inspection area T are brought into direct contact with each other, there is a risk that the surface of the oscillator 11a may be scratched. Therefore, the wedge 12 also functions as a buffer between the transducer 11 and the cylindrical structure P (inspection area T).
The material of the wedge 12 may be one that does not affect the transmission of ultrasonic waves and has a certain degree of resistance (strength) to sliding with the cylindrical structure P. More specifically, the wedge 12 may be made of a resin. This makes it easy to mold the wedge 12 and reduces the cost of replacement.

The size of the ultrasonic probe 10 in this embodiment depends mainly on the area of the vibrator 11a of the transducer 11, but may be, for example, 50 mm or less, more preferably 30 mm or less. This makes it possible to measure small-diameter cylindrical structures P, which was difficult to measure using conventional non-immersion ultrasonic flaw detection. In consideration of measurement efficiency, it is preferable that the size of the ultrasonic probe 10 is 10 mm or more. This allows efficient measurement of the inspected portion T of the cylindrical structure P without needlessly increasing the number of measurements.

The measurement of the internal structure by the ultrasonic probe 10 of this embodiment will be described with reference to FIG.
3 shows a state in which the ultrasonic probe 10 is in contact with an inspection site T of the cylindrical structure P by a support 20 and a drive mechanism 30, which will be described later.

First, ultrasonic waves emitted from the transducer 11 (vibrator 11a) are incident on the surface of the tubular structure P (inspection area T) at an oblique angle via the wedge 12. If the information to be obtained relates to the internal structure of the welded portion W (presence or absence of internal defects D), it is preferable to bring the ultrasonic probe 10 into contact with the inner wall surface of the tubular structure P near the welded portion W, as shown in FIG. 3, and to direct ultrasonic waves toward the welded portion W. By bringing the ultrasonic probe 10 into contact with the inner wall of the tubular structure P, which is smoother than the surface of the welded portion W, it becomes easier to ensure adhesion, enabling stable measurements.

The ultrasonic waves emitted from the transducer 11 are reflected by the opposite surface (outer wall side) of the cylindrical structure P from the surface (inner wall side) where they entered, and head toward the welded part W. At this time, if an internal defect D is present in the welded part W, the ultrasonic waves will be reflected by the internal defect D and return to the ultrasonic probe 10. Based on the intensity of this reflection (echo) and the time it takes for it to return, it is possible to determine the presence and location of the internal defect D.

At this time, by rotating the support 20 using the rotation drive mechanism 50 while keeping the ultrasonic probe 10 in contact with the inspection area T, it is possible to determine the presence or absence and position of the internal defect D in the circumferential direction of the cylindrical structure P, as well as the range (length) of the internal defect D.

The support 20 supports the ultrasonic probe 10. The support 20 is also connected to the drive mechanism 30 (described below) as well as the lift drive mechanism 40 and the rotation drive mechanism 50, allowing the ultrasonic probe 10 to be moved by driving these drive mechanisms.

The support 20 is not particularly limited as long as it has a shape and material that can support the ultrasonic probe 10 and allow it to be driven in each direction (XYZ directions and rotation). The support 20 may be, for example, a rod-shaped member (shaft, rod, etc.). There is also no particular limit to the width (diameter) or length of the support 20. For example, it can be designed to match the cylindrical structure P to be measured.

The support means for the ultrasonic probe 10 on the support 20 is not particularly limited. For example, the ultrasonic probe 10 may be attached to the side of the support 20, but as shown in Figures 1 and 2, the ultrasonic probe 10 may be supported at the lower end of the support 20 via a holding member 21. In this case, as shown in Figures 1(B) and 2(B), it is preferable to arrange the ultrasonic probe 10 so that the portion protruding outside the diameter of the support 20 is small. This makes it possible for the ultrasonic probe 10 to pass through the diameter of the support 20 when it is introduced into the space inside the cylindrical structure P. Therefore, it is possible to expand the range of cylindrical structures P that can be applied as measurement targets, and in particular, it is possible to measure cylindrical structures with small diameters, which were difficult to do with conventional non-immersion ultrasonic flaw detection.

Moreover, it is preferable that the angle of the holding member 21 can be adjusted so that the ultrasonic probe 10 and the inspection area T are parallel to each other. This can further improve the adhesion between the ultrasonic probe 10 and the inspection area T, and it becomes possible to stably perform measurements based on non-immersion ultrasonic flaw detection.
There is no particular limitation on the means for adjusting the angle of the holding member 21. For example, the holding member 21 may be provided with a mechanism (preferably remotely operable) for varying the angle, or the structure or material of the holding member 21 may be selected such that it can be deformed by a force (force pressed against the test site T) generated by movement of the support 20 (holding member 21) by the drive mechanism 30 described later.

The driving mechanism 30 is provided outside the cylindrical structure P and is used to perform a driving step that moves the support 20 in the radial direction of the cylindrical structure P. As a result, what is introduced into the cylindrical structure P is mainly the ultrasonic probe 10 and the support 20, which are easy to miniaturize. Therefore, for a small-diameter cylindrical structure, measurement based on ultrasonic flaw detection is possible from the inner wall side of the cylindrical structure P.

A specific example of the driving mechanism 30 is, for example, an XY stage 31 connected to the upper end of the support 20 as shown in FIG.
By using the XY stage 31, it becomes easy to control the position of the support 20 (and the ultrasonic probe 10) on the XY plane with high precision. Therefore, the ultrasonic probe 10 can be brought into contact with the inspection site T at an appropriate position from the inner wall side of the cylindrical structure P, and measurement precision can be improved.
Furthermore, because the XY stage 31 causes the ultrasonic probe 10 to move in parallel in the radial direction of the cylindrical structure P via the support 20, the ultrasonic probe 10 receives a force from the support 20 along the radial direction of the cylindrical structure P (a force pressing the ultrasonic probe 10 toward the inspection area T) when the ultrasonic probe 10 approaches or comes into contact with the inspection area T. This improves the adhesion between the ultrasonic probe 10 and the inspection area T, making it possible to stably perform measurements based on non-immersion ultrasonic flaw detection.

As another specific example of the driving mechanism 30, for example, as shown in FIG. 2, a tilting mechanism 32 is provided at the upper end of the support 20.
The tilting mechanism 32 in this embodiment may be any mechanism capable of tilting the support 20 in the radial direction of the cylindrical structure P, and the structure is not particularly limited.

4A and 4B are schematic diagrams showing an example of the structure of the tilt mechanism, which is the drive mechanism in this embodiment. Note that Fig. 4A and Fig. 4B each show an example of a tilt mechanism having a different structure.
As shown in FIG. 4, the tilt mechanism 32 includes a rotation shaft 32a and an angle adjustment unit 32b.
The rotating shaft 32a may be connected to the support 20 and driven to rotate around the axial center, and is arranged so that the axis (axial center) of the rotating shaft 32a is perpendicular to the central axis of the support 20 (Z direction in FIG. 4). In other words, the axial direction of the rotating shaft 32a is arranged to face the Y direction in FIG. 1 and FIG. 2 (perpendicular to the paper surface in FIG. 4). This makes it possible to tilt the support 20 toward the radial direction (X direction in FIG. 4) of the cylindrical structure P by driving the rotating shaft 32a to rotate. Note that the X direction and the Y direction in FIG. 4 indicate the relative directions with respect to the Z direction, and are not fixed directions themselves. In other words, the X direction and the Y direction in FIG. 4 are interchangeable with each other.
The angle adjustment unit 32b acts on the rotation shaft 32a to rotate the rotation shaft 32a. By rotating the rotation shaft 32a via the angle adjustment unit 32b, it becomes possible to easily adjust the angle at which the support 20 is tilted.

Specific examples of the angle adjustment unit 32b include, as shown in FIG. 4(A), a rod- or plate-shaped member that connects to the rotating shaft 32a and a drive unit (not shown) that drives this member up and down, and as shown in FIG. 4(B), a rod- or plate-shaped member that can be in contact with or out of contact with the rotating shaft 32a and a drive unit (not shown) that drives this member up and down and left and right. In this case, the drive unit that drives the member is not particularly limited, but an air cylinder, which is an actuator that consumes little power, is preferably used.

The angle adjustment unit 32b shown in Fig. 4(A) connects the rotating shaft 32a to a member, and the rotating shaft 32a rotates with the up and down movement of the member. For example, as shown in the right diagram of Fig. 4(A), when the member of the angle adjustment unit 32b is driven downward from the initial position, the rotating shaft 32a rotates clockwise in conjunction with the movement of the member, and as a result, the support 20 connected to the rotating shaft 32a tilts toward the radial direction of the cylindrical structure P (the X direction in Fig. 4).
In addition, the angle adjustment unit 32b shown in Fig. 4(B) can switch between contact and non-contact states between the rotating shaft 32a and the member as the member is driven, thereby rotating the rotating shaft 32a. For example, as shown in the right diagram of Fig. 4(B), by driving the member of the angle adjustment unit 32b downward and leftward from the initial position, the member presses the lower part of the rotating shaft 32a, causing the rotating shaft 32a to rotate clockwise, and as a result, the support 20 connected to the rotating shaft 32a is tilted toward the radial direction of the cylindrical structure P (the X direction in Fig. 4).

By using the tilting mechanism 32, the ultrasonic probe 10 arranged at the lower end of the support 20 can be pressed against the inspection area T from the inner wall side of the cylindrical structure P. This improves the adhesion between the ultrasonic probe 10 and the inspection area T, making it possible to stably perform measurements based on non-immersion ultrasonic flaw detection.

As described above, the support 20 (and the ultrasonic probe 10 ) also moves in directions other than the radial direction of the cylindrical structure P by the driving mechanism 30 .
The lifting/lowering drive mechanism 40 and the rotation drive mechanism 50 are respectively connected to the support 20 and are used to lift/lower and rotate the support 20 (and the ultrasonic probe 10).
Similarly to the drive mechanism 30, the lifting drive mechanism 40 and the rotation drive mechanism 50 are provided outside the cylindrical structure P. This reduces the amount of configuration introduced into the space inside the cylindrical structure P together with the drive mechanism 30, and enables measurement based on ultrasonic flaw detection from the inner wall side of a small-diameter cylindrical structure.

The lifting and lowering drive mechanism 40 is not particularly limited as long as it can move the support 20 and the drive mechanism 30 up and down (moving in the Z direction) along the central axis direction of the cylindrical structure P, as shown in Figures 1 and 2.
In the measuring device 1A of this embodiment, the ultrasonic probe 10 is introduced into the space within the cylindrical structure P by driving the lifting drive mechanism 40 (introduction step).

The rotation drive mechanism 50 is for performing a rotation step that moves the support 20 in the circumferential direction of the cylindrical structure P, and is not particularly limited as long as it can rotate the support 20 as shown in Figures 1 and 2. Note that when driving the rotation drive mechanism 50, it is preferable to align the rotation axis of the support 20 with the central axis of the cylindrical structure P using the above-mentioned drive mechanism 30 before driving the rotation drive mechanism 50. This stabilizes the rotation movement of the support 20, making it possible to obtain highly accurate information even when measuring the circumferential direction of the cylindrical structure P. In this case, an XY stage 31 is particularly preferably used as the drive mechanism 30.

As described above, in the present embodiment, the device for measuring the internal structure of a cylindrical structure (measuring device 1A) and the method for measuring the internal structure of a cylindrical structure using this measuring device 1A introduces the ultrasonic probe 10 supported by the support 20 into the space inside the cylindrical structure P, and moves this support 20 in the radial direction of the cylindrical structure P using a driving mechanism 30, so that when the ultrasonic probe 10 approaches and contacts the inspection site T of the cylindrical structure P, a force is applied to the ultrasonic probe 10 from the support 20 pressing it against the inspection site T of the cylindrical structure P. This improves the adhesion between the ultrasonic probe 10 and the inspection site T, making it possible to stably perform measurements based on non-immersion ultrasonic flaw detection.
Furthermore, by providing the driving mechanism 30 outside the cylindrical structure P, the ultrasonic probe 10 and the support 20, which can be easily miniaturized, are mainly introduced into the cylindrical structure P. This makes it possible to perform ultrasonic testing based measurements from the inner wall side of a cylindrical structure, even for small-diameter cylindrical structures that were difficult to measure using conventional non-immersion ultrasonic testing.

The internal structure measuring device for a cylindrical structure in this embodiment (measuring device 1A) can be used as an inspection device for cooling water piping in a nuclear fusion device, which is one aspect of the present invention.
More specifically, by setting the cylindrical structure P to be measured by the measuring device 1A to be a cooling water piping in a nuclear fusion device, the measuring device 1A can function as an inspection device for the cooling water piping in the nuclear fusion device of the present invention.

The cooling water piping inspection device in the nuclear fusion device of the present invention (hereinafter also referred to simply as the "inspection device") is used to inspect the cooling water piping used in the nuclear fusion device, and the type of the cooling water piping itself is not particularly limited.
In general, a nuclear fusion device is provided with a doughnut-shaped vacuum vessel for performing nuclear fusion, and various devices (vacuum vessel internal devices) are provided inside the vacuum vessel. Since these devices (vacuum vessel internal devices) are basically water-cooled, the inspection target of the inspection device of the present invention is the cooling water piping used for water-cooling the vacuum vessel internal devices. In particular, the cooling water piping in the vacuum vessel internal devices is often small in diameter, and when installing or replacing the cooling water piping, it may be necessary to cut or connect the piping, and even inspect the connection part. However, it has been difficult to secure the work space and work time when performing work such as inspection of the cooling water piping in the vacuum vessel internal devices.

On the other hand, by using the internal structure measuring device for cylindrical structures (measuring device 1A) shown in this embodiment as the inspection device of the present invention, it becomes possible to stably perform measurements based on non-immersion ultrasonic flaw detection on small-diameter cylindrical structures without complicating or enlarging the device. In other words, it becomes possible to perform appropriate inspections of cooling water piping even under harsh working conditions, such as the inspection of cooling water piping in a nuclear fusion device.

As an inspection device of the present invention, it is preferable to provide each component constituting the measuring device 1A with performance suitable for maintenance work within a nuclear fusion device. For example, the materials of each component of the measuring device 1A as an inspection device may be heat-resistant and radiation-resistant.

[Second embodiment]
FIG. 5 is a schematic explanatory diagram showing an apparatus for measuring the internal structure of a cylindrical structure according to a second embodiment of the present invention.
The measuring apparatus 1B according to the second embodiment includes both the XY stage 31 and the tilt mechanism 32 shown in the measuring apparatus 1A in the first embodiment as the driving mechanism 30. Note that the description of the same components as those in the first embodiment will be omitted.

In the measuring device 1B of this embodiment, by providing both the XY stage 31 and the tilt mechanism 32 as the driving mechanism 30, it becomes possible to control the position of the support 20 (and the ultrasonic probe 10) with even higher accuracy.
For example, the XY stage 31 is used to move the support 20 in parallel so as to reduce the distance between the ultrasonic probe 10 and the inspection site T while aligning the rotation axis of the support 20 (the rotation axis in the rotation drive mechanism 50) with the central axis of the cylindrical structure P. In this state, the tilt mechanism 32 is used to press the ultrasonic probe 10 against the inspection site T. This makes it possible to appropriately maintain the contact between the ultrasonic probe 10 and the inspection site T even in a measurement involving rotational movement by the rotation drive mechanism 50. In this case, the tilt angle required to bring the ultrasonic probe 10 into contact with the inspection site T can be made smaller than the angle required when the tilt mechanism 32 is tilted (moved) alone. In other words, it is possible to maintain the required contact while reducing the load on the drive and control of the tilt mechanism 32.

The measuring device 1B of this embodiment is provided with both a mechanism (XY stage 31) for translational movement relative to the radial direction of the cylindrical structure P and a mechanism for tilting (tilting mechanism 32) when moving the support 20 (and ultrasonic probe 10) in the radial direction of the cylindrical structure P, thereby making it possible to further improve the adhesion between the cylindrical structure P (inspection area T) and the ultrasonic probe 10. This makes it possible to perform measurements based on non-immersion ultrasonic flaw detection in a more stable manner.

The internal structure measuring device for cylindrical structures in this embodiment (measuring device 1B) can be used as an inspection device for cooling water piping in a nuclear fusion device, which is one aspect of the present invention, in the same way as measuring device 1A described above.

[Third embodiment]
FIG. 6 is a schematic explanatory diagram showing an apparatus for measuring the internal structure of a cylindrical structure according to a third embodiment of the present invention.
The measuring device 1C according to the third embodiment is the measuring device 1A according to the first embodiment, further comprising a contact medium supply unit 60 for supplying a contact medium M between the inspection site T and the ultrasonic probe 10. Note that a description of the same components as those in the first embodiment will be omitted.

The measuring device 1C of this embodiment is provided with a contact medium supply unit 60 that supplies a contact medium M between the area to be inspected T and the ultrasonic probe 10 as a means for improving the adhesion between the area to be inspected T and the ultrasonic probe 10.

As described above, the presence of gas (air) between the area to be inspected T and the ultrasonic probe 10 reduces the measurement accuracy of ultrasonic flaw detection. Therefore, in the measuring device 1C of this embodiment, in addition to position adjustment by the driving mechanism 30, the contact medium M is supplied to minute gaps (voids) that may exist due to the surface shape of the area to be inspected T and the surface shape of the ultrasonic probe 10 (wedge 12), thereby improving adhesion.

The contact medium M is not particularly limited as long as it can eliminate gaps at the contact surface between the test area T and the ultrasonic probe 10 and improve adhesion. Examples include liquids such as water and oil, as well as gel-like substances.

The contact medium supply unit 60 may include a supply line 61 that transports the contact medium M and a supply nozzle 62 that discharges the contact medium M between the inspection site T and the ultrasonic probe 10. As shown in FIG. 6, the contact medium supply unit 60 is preferably supported by a holding member 21 together with the ultrasonic probe 10. This allows the contact medium supply unit 60 to move together with the ultrasonic probe 10, making it easier to accurately supply the contact medium M to the gap between the ultrasonic probe 10 and the inspection site T.

Furthermore, it is preferable that the holding member 21 in this embodiment is also angle adjustable as described above. In this case, in addition to adjusting the angle so that the ultrasonic probe 10 and the area to be inspected T are parallel to each other in order to bring the ultrasonic probe 10 and the area to be inspected T into close contact with each other, it is also preferable that the angle can be adjusted so that the ultrasonic probe 10 is slightly upward to ensure that the contact medium M is distributed throughout the area.

The measuring device 1C of this embodiment uses a contact medium M as a means for further improving the adhesion between the tubular structure P (inspection area T) and the ultrasonic probe 10. Furthermore, instead of constantly immersing the inspection area T in water, it is possible to use the contact medium M only when necessary (during measurement) or in the necessary places. This enables rapid and highly accurate measurement when acquiring information on the internal structure from the inner wall side of the tubular structure P, and also makes it possible to expand the range of applicable measurement targets (tubular structures).

The internal structure measuring device for cylindrical structures in this embodiment (measuring device 1C) can be used as an inspection device for cooling water piping in a nuclear fusion device, which is one aspect of the present invention, in the same way as measuring device 1A described above.

[Fourth embodiment]
FIG. 7 is a schematic explanatory diagram showing an apparatus for measuring the internal structure of a cylindrical structure according to a fourth embodiment of the present invention.
The measuring device 1D according to the fourth embodiment is one in which a reduced diameter portion 22 is provided in a part of the support 20 shown in the measuring device 1A according to the first embodiment. Note that a description of the same configuration as that of the first embodiment will be omitted.

The measuring device 1D of this embodiment is preferably used in a case where a narrow portion N is provided in the space inside a cylindrical structure P so that the diameter of the tube is partially reduced.
For example, as shown in Figure 7, if a narrow portion N is provided in a part of the cylindrical structure P, if the diameter of the support 20 is uniform, the support 20 and the narrow portion N may come into contact with each other when moved by the driving mechanism 30, which may hinder the approach and contact between the ultrasonic probe 10 and the inspection area T.

On the other hand, as shown in FIG. 7, the support 20 of this embodiment has a reduced diameter portion 22 in a portion thereof, which makes it possible to avoid contact between the support 20 and the narrow portion N when moved by the drive mechanism 30. This makes it possible to measure a cylindrical structure P that is difficult to move the ultrasound probe 10 to the inspection site T due to the presence of the narrow portion N.

The shape and size of the reduced diameter section 22 are not particularly limited. In addition, the structure of the reduced diameter section 22 may be, for example, a hollow cylindrical structure to reduce weight while maintaining rigidity.

The measuring device 1D of this embodiment can ensure close contact between the ultrasonic probe 10 and the area to be inspected T even for a cylindrical structure P having a special structure (narrow portion N). This makes it possible to perform rapid and highly accurate measurements when obtaining information about the internal structure from the inner wall side of a cylindrical structure P where a narrow portion N exists.

Furthermore, the internal structure measuring device for a cylindrical structure in this embodiment (measuring device 1D) can be used, like the measuring device 1A described above, as an inspection device for cooling water piping in a nuclear fusion device, which is one aspect of the present invention.
In particular, the cooling water piping in the equipment inside the vacuum vessel of a nuclear fusion device not only has a small diameter, but also often has a special structure such as a narrow section N. Therefore, by using the internal structure measuring device for a cylindrical structure (measuring device 1D) shown in this embodiment as the inspection device of the present invention, it becomes much easier to perform appropriate inspection of the cooling water piping even under severe working conditions.

The above-mentioned embodiment shows an example of the device for measuring the internal structure of a cylindrical structure and the method for measuring the internal structure of a cylindrical structure. The device for measuring the internal structure of a cylindrical structure and the method for measuring the internal structure of a cylindrical structure according to the present invention are not limited to the above-mentioned embodiment, and the device for measuring the internal structure of a cylindrical structure and the method for measuring the internal structure of a cylindrical structure according to the above-mentioned embodiment may be modified within the scope of the gist of the claims.

The device and method for measuring the internal structure of a tubular structure according to the present invention are used to obtain information on the internal structure of a tubular structure, and are particularly suitable for obtaining information on the internal structure of a small-diameter tubular structure (pipe) and for maintenance work.
The cooling water piping inspection device of the present invention for a nuclear fusion device is used to inspect various types of cooling water piping used in the nuclear fusion device.

1A, 1B, 1C, 1D Internal structure measuring device for cylindrical structure, 10 Ultrasonic probe, 11 Transducer, 11a Oscillator, 12 Wedge, 20 Support, 21 Holding member, 22 Reduced diameter portion, 30 Drive mechanism, 31 XY stage, 32 Tilt mechanism, 32a Rotation axis, 32b Angle adjustment member, 40 Lifting drive mechanism, 50 Rotation drive mechanism, 60 Contact medium supply unit, 61 Supply line, 62 Supply nozzle, D Internal defect, M Contact medium, N Narrow portion, P Cylindrical structure, T Inspected portion, W Welded portion

Claims (6)

An ultrasonic probe that is introduced into a space within a cylindrical structure;
A support for supporting the ultrasonic probe;
A drive mechanism for moving the support in a radial direction of the cylindrical structure,
2. The apparatus for measuring the internal structure of a cylindrical structure, wherein the driving mechanism is provided outside the cylindrical structure. The device for measuring the internal structure of a cylindrical structure according to claim 1, characterized in that the driving mechanism includes an XY stage that translates the support in the radial direction of the cylindrical structure, and a tilting mechanism that tilts the support in the radial direction of the cylindrical structure. The internal structure measuring device for a cylindrical structure according to claim 1 or 2, characterized in that the ultrasonic probe emits ultrasonic waves in a two-dimensional direction. The device for measuring the internal structure of a cylindrical structure according to claim 1 or 2, characterized in that a contact medium is supplied between the inspection area on the inner wall of the cylindrical structure and the ultrasonic probe. An introduction step of introducing an ultrasonic probe supported by a support into a space within a cylindrical structure;
A driving step of moving the support in a radial direction of the tubular structure,
A method for measuring the internal structure of a cylindrical structure, characterized in that the driving step is performed by a driving mechanism provided outside the cylindrical structure. 3. An inspection device for cooling water piping in a nuclear fusion device, comprising the internal structure measuring device for a cylindrical structure according to claim 1 or 2.