WO2015059916A1

WO2015059916A1 - Ultrasonic inspection device and ultrasonic inspection method

Info

Publication number: WO2015059916A1
Application number: PCT/JP2014/005306
Authority: WO
Inventors: 畑中　健一; 裕幸安部; 田中　健二; 峰寛中川; 元則安永
Original assignee: 積水化学工業株式会社; 新日本非破壊検査株式会社
Priority date: 2013-10-24
Filing date: 2014-10-20
Publication date: 2015-04-30

Abstract

The present invention provides an ultrasonic inspection device that is capable of freely expanding and contracting within a pipe and that achieves additional compactness through diameter reduction to a minimum size. The present invention is an ultrasonic inspection device that can be inserted inside a pipe, said ultrasonic inspection device including a shaft part, an expansion and contraction arm, a traveling part, an extension and contraction part, an extension and contraction control part, a motor, an ultrasonic probe, and an acoustic reflection part. The expansion and contraction arm is provided so as to protrude from the outer periphery of the shaft part and can expand and contract radially around the axis of the shaft part. The expansion and contraction arm is made to expand and contract through the control of the extension and contraction part by the extension and contraction control part. The traveling part is provided on the leading end of the expansion and contraction arm and abuts the inner wall of the pipe. The motor is directly or indirectly fixed to the shaft part and is disposed so as to emit ultrasound having a sound axis matching the axis of the shaft part. The acoustic reflection part reflects the ultrasound emitted by the ultrasonic probe in a direction in which the ultrasound is perpendicularly incident on the inner wall of the pipe.

Description

Ultrasonic inspection apparatus and ultrasonic inspection method

The present invention relates to an ultrasonic inspection apparatus that can be inserted into a tube and an ultrasonic inspection method using the same. More specifically, the present invention relates to a compact ultrasonic inspection apparatus that can be expanded and contracted in a tube and an ultrasonic inspection method using the same.
Furthermore, the present invention also relates to a method for testing a thickness of a metal multilayer body and a layer thickness test apparatus for a metal multilayer body. In particular, the present invention also relates to a test method for the degree of deterioration of buried piping and an apparatus therefor.

An ultrasonic device has been developed that is inserted into a pipe and transmits ultrasonic waves to the inner wall of the pipe to measure the damaged state of the pipe and the thickness of the pipe.

For example, a pipe thinning measuring apparatus described in Japanese Patent Application Laid-Open No. 2011-158392 (Patent Document 1) is provided on a front side of a measurement carriage that is inserted into a pipe arranged in a horizontal plane or an inclined plane. A pipe thinning measuring device having a thickness measuring means for measuring the thickness of a pipe and a propulsion means arranged at the rear part of the measuring carriage to advance the measuring carriage, the measuring carriage being a cylindrical casing arranged at the center And at least three parallel link mechanisms that protrude radially outward from the outer peripheral portion of the cylindrical casing, and omnidirectional moving wheels that are front-rear pairs provided on the radially outer side of each parallel link mechanism, and have a thickness The measuring means includes a motor disposed in the cylindrical casing, a sensor holder that is rotationally driven by the motor and disposed at the axial center position of the cylindrical casing, and is mounted perpendicular to the sensor holder. And a thickness measuring sensor, moreover, a part of the radially outer cylindrical casing, wherein the weight to hold the position of the measuring carriage in a predetermined direction is provided.
The at least three parallel link mechanisms include a fixing ring fixedly arranged on one side of the front and rear of the cylindrical casing, a sliding ring arranged movably in the front-rear direction on the other side of the cylindrical casing, the fixing ring, and the aforementioned A cross arm whose base is pivotably connected to the sliding ring, a link plate provided on the front side of each cross arm and provided with omnidirectional wheels on both the front and rear sides, and a fixed ring for fixing the sliding ring And a spring urging in the direction.

Also, an ultrasonic inspection device for a tube described in Japanese Patent Application Laid-Open No. 2001-83124 (Patent Document 2) has an ultrasonic probe and a rotating body placed in the tube, and is inclined 45 degrees toward the front side of the rotating body. The mirror is provided, the ultrasonic wave emitted from the ultrasonic probe is reflected by the mirror, and the reflected wave is detected by the ultrasonic probe.

Furthermore, conventionally, a method of measuring the thickness of the constituent layers of the multilayer body by a non-destructive method has been adopted.
For example, in Japanese Patent Laid-Open No. 60-123712 (Patent Document 3), an ultrasonic probe is installed on the surface of a tube to emit ultrasonic waves in the radial direction and detect reflected waves from the inner surface of the opposite lining. A method for measuring the inner surface lining thickness is disclosed, wherein the lining thickness is measured from the energy loss of the reflected wave.

Japanese Patent Application Laid-Open No. 63-3211 (Patent Document 4) discloses the measurement of the thickness of a fiber reinforced composite layer formed integrally with the surface of a metal body and made of a reinforced fiber and a metal matrix. The ultrasonic wave is transmitted toward the surface of the fiber reinforced resin composite layer and the reflected wave is sequentially received, and the time from the transmission of the ultrasonic wave to the reception of the final reflected wave by the reinforcing fiber is converted into the thickness of the fiber reinforced composite layer. A method for measuring the thickness of a fiber-reinforced composite layer using ultrasonic waves is disclosed.

JP 2011-158392 A JP 2001-83124 A JP-A-60-123712 Japanese Patent Laid-Open No. Sho 63-3211

Since the apparatus of Patent Document 1 is aligned only by the urging force of a spring (specifically, a tension spring), it is not possible to reduce or expand the diameter within the pipe, and it can be applied to a pipe whose diameter changes. Have difficulty.

The device of Patent Document 2 uses a rotational drive mechanism using a water jet nozzle, and therefore cannot be applied to a pipe whose diameter changes.

The method of patent document 3 measures the thickness of the concrete lining layer of the composite pipe comprised from a metal and concrete. In this method, it is necessary to install a contact-type ultrasonic probe outside the composite tube. Therefore, when applied to the buried pipeline, an excavation work is required. Furthermore, the method of Patent Document 3 is a method of measuring the lining thickness, and does not describe measuring the thickness of the metal layer.
The method of patent document 4 is a water immersion type ultrasonic method, and measures the thickness of the fiber reinforcement layer which is an ultrasonic incident side. However, it is not described that the thickness of the metal layer as the back layer can be measured.

Accordingly, an object of the present invention is to provide an ultrasonic inspection apparatus that can freely expand and contract within a tube and an ultrasonic inspection method using the same.

Furthermore, another object of the present invention is to provide a non-destructive method in the case where a measurement object is a composite layer having a porous layer on the surface of a metal layer, which is considered to have a particularly large ultrasonic attenuation in general technical common sense. Then, it is providing the method which can acquire the information regarding the thickness of a metal layer.

(1)
The present invention is an ultrasonic inspection apparatus that can be used for internal inspection of a tube. The ultrasonic inspection apparatus of the present invention includes a shaft part, an expansion / contraction arm, a traveling part, an expansion / contraction part, an expansion / contraction control part, a motor, an ultrasonic probe, and an acoustic reflection part.
The expansion / contraction arm protrudes from the outer peripheral portion of the shaft portion. Furthermore, the expansion / contraction arm can be expanded / contracted in the radial direction centered on the axial center of the shaft portion.
The traveling unit is provided on the expansion / contraction arm.
Further, the expansion / contraction arm can be expanded / contracted by controlling the expansion / contraction section by the expansion / contraction control section. For this reason, the diameter reduction and diameter expansion in a pipe become free.
The motor is directly or indirectly fixed to the shaft portion.
The ultrasonic probe is arranged to transmit ultrasonic waves in the axial direction of the shaft portion.
The acoustic reflector reflects the ultrasonic wave transmitted from the ultrasonic probe from the axial direction to the radial direction.

When the ultrasonic inspection apparatus of the present invention is inserted into a tube, the expanding / contracting arm expands so as to stretch toward the inner wall of the tube, and the traveling portion provided on the expanding / contracting arm contacts the inner wall of the tube. Thereby, the ultrasonic inspection apparatus is held. Moreover, the expansion / contraction part can be expanded / contracted to expand / contract the expansion / contraction arm. For this reason, the diameter reduction and diameter expansion in a pipe become free.
The ultrasonic inspection apparatus of the present invention includes an internal moving part inserted into the tube (specifically, in the case of (1), an expansion / contraction arm, a traveling part, an expansion / contraction part, a motor, an ultrasonic probe, An acoustic reflection unit) and an external operation unit (specifically, in the case of (1), an expansion / contraction control unit) that is operated outside the tube. In this specification, the ultrasonic inspection apparatus is inserted into the tube. When it describes, it means that an internal movement part is inserted in a pipe | tube.

The tube into which the ultrasonic inspection apparatus of the present invention is inserted is not particularly limited as long as it can be an object of ultrasonic inspection. For example, a metal tube, a resin tube, a porous material such as a mortar or a resin, etc. A lined metal tube is an example.

Further, in the present specification, the diameter described with respect to the dimensions of the pipe means the inner diameter unless otherwise specified.

Further, the fact that the ultrasonic wave is transmitted in the axial direction of the shaft portion is not limited to the transmission of the ultrasonic wave on the axial center, and is preferably within ± 5 mm parallel to the axial center and within the radial direction from the axial center. Includes transmission with a deviation within ± 3 mm and transmission with a deviation in a direction inclined ± 5 degrees, preferably ± 3 degrees from the axis.
For example, the position at which the acoustic reflection unit reflects the ultrasonic waves from the axial direction to the radial direction is preferably on the axial center, but the position may be within ± 5 mm from the axial center to the radial direction, and ± 3 mm. It is more preferable that Thereby, a preferable sensitivity can be obtained. For example, the echo height can be reduced to a maximum of about half (decrease by a maximum of 6 dB as a specific example).
Furthermore, the ultrasonic wave reflected by the acoustic reflector is preferably incident at 90 degrees with respect to the tangent to the inner wall of the tube, but the incident angle may be not less than 85 degrees and not more than 95 degrees. Furthermore, it is more preferable from the viewpoint of sensitivity if the incident angle is 88 degrees or more and 92 degrees or less, particularly 90 degrees. For example, the echo height can be reduced to a maximum of about half (decrease by a maximum of 6 dB as a specific example).

In the above (1), the motor may be a hollow shaft motor including a hollow rotating member and a non-rotating member surrounding the hollow rotating member.
When the ultrasonic inspection apparatus of the present invention includes a hollow shaft motor, the ultrasonic probe may be fixedly connected to the non-rotating member. In addition, in this specification, continuous fixing means both the aspect fixed directly via other members, and the aspect fixed indirectly via other members.

音響 By providing an acoustic reflection part that reflects ultrasonic waves in a rotatable manner, the ultrasonic probe can be provided in a fixed state. As a result, the size of the ultrasonic inspection apparatus in the radial direction around the axial center of the shaft portion (particularly, the size when the expansion / contraction arm is most contracted) can be made compact. For example, it is possible to reduce the size more efficiently than when the ultrasonic probe is provided so as to extend in the radiation direction and the ultrasonic probe itself is rotated about the axis.

When the ultrasonic inspection apparatus of the present invention includes a hollow shaft motor, the acoustic reflection unit may be provided so as to be rotatable in conjunction with the hollow rotating member.

By using a hollow shaft motor for rotation of the acoustic reflector, the ultrasonic probe itself can be disposed in the axial direction because the ultrasonic wave propagates through the hollow portion of the hollow rotating member. . This also makes it possible to reduce the size of the ultrasonic inspection apparatus in the radial direction.

(2)
The ultrasonic inspection apparatus of the present invention may include an expansion / contraction part that expands / contracts the expansion / contraction arm. The telescopic part includes a movable part, and the movable part can be provided so as to move in the axial direction of the shaft part.

In this case, the expansion / contraction arm expands / contracts with expansion / contraction of the expansion / contraction part, and the expansion / contraction direction of the expansion / contraction part is the axial center direction of the shaft part. As a result, the size of the ultrasonic inspection apparatus in the radial direction around the axis of the shaft can be made compact. For example, the size reduction can be achieved more efficiently than in the case where the expansion / contraction part is disposed so as to expand and contract in the radial direction.

(3)
In the ultrasonic inspection apparatus of the present invention described in (1) above, the expansion / contraction part may be arranged on the outer peripheral part of the shaft part so as to expand and contract in the axial direction of the shaft part.

In this case, since the expansion / contraction direction of the expansion / contraction part is the axial direction of the shaft part, even if the expansion / contraction part itself is provided on the outer peripheral part of the shaft part, the radiation direction of the ultrasonic inspection apparatus around the axis The size of can be made compact. For example, it is possible to reduce the size more efficiently than in the case where an expansion / contraction part is disposed on the outer peripheral part of the shaft part so as to expand and contract in the radial direction.

(4)
In the ultrasonic inspection apparatus according to the present invention described in (1) and (2) above, the stretchable part may constitute at least a part of the shaft part.

In this case, since the function of the expansion / contraction part is assigned to at least a part of the shaft part, a structure in which the expansion / contraction part having a relatively large size is not provided on the outer peripheral part of the shaft part is possible. For example, it is possible to provide no expansion / contraction part at the outer peripheral part of the shaft part, or an auxiliary member such as an auxiliary spring for assisting the operation of the expansion / contraction part on the outer peripheral part of the shaft part (the auxiliary member is also a component of the expansion / contraction part) It is also possible to provide only. Therefore, the magnitude | size of the radial direction centering on the axial center of an axial part of an ultrasonic inspection apparatus can be made compact.

(5)
The ultrasonic inspection apparatus of the present invention may be configured such that when the expansion / contraction arm has a storage portion and the expansion / contraction arm is reduced, the expansion / contraction portion is stored in the storage portion.

This makes it possible to reduce the size of the ultrasonic inspection apparatus in the radial direction around the axis of the shaft.

(6)
The ultrasonic inspection apparatus of the present invention may include at least a housing portion that houses a motor. In this case, when the expansion / contraction arm is most contracted, it is preferable that the entire expansion / contraction arm overlaps the projection of the casing in the axial direction.

In this case, the size of the ultrasonic inspection apparatus in the radial direction when the expansion / contraction arm is most contracted can be made compact.

(7)
It is preferable that the base ends of each of the plurality of expansion / contraction arms are pivotally attached at two locations on one end side and the other end side of the shaft portion in the axial direction. In this case, the expansion / contraction arm arranged on one end side and the expansion / contraction arm arranged on the other end side are opposite to each other in the axial direction.
The base ends of each of the plurality of expansion / contraction arms are arranged at equal intervals around the axis at a predetermined position in the axial direction, and the expansion / contraction arms have an angle not exceeding 90 degrees in the radial direction with the base end as a center. It is configured to be rotatable.

In this case, the expansion / contraction arm extends substantially along the axis of the shaft when it is most contracted, and at the time of expansion, the base end located at a predetermined position is the center, and the tip is in the reflection direction from the axis. The tip rises away from the center of the screen, and at the time of reduction, the tip falls down so as to approach the axis. Accordingly, the structure of each of the expansion / contraction arms can be simplified, and the size of the ultrasonic inspection apparatus in the radial direction around the axis of the shaft portion can be made compact.
Further, in this case, the rotation angle around the base end of the expansion / contraction arm does not exceed 90 degrees. In this way, since the expansion / contraction arm having a simple structure moves within a predetermined movable range in the axial direction, the size of the axial portion of the ultrasonic inspection apparatus in the axial direction can be made compact.
Therefore, the space occupied by the trajectory of the operation of the expansion / contraction arm can be reduced. For this reason, the direction change in a branch pipe like a cheese type piping becomes easy.

Furthermore, since the shaft body is aligned stably in the tube, the ultrasonic inspection apparatus is stably held in the tube.

(8)
In the ultrasonic inspection apparatus according to the present invention described in (1) to (7) above, the expansion / contraction arm includes a long arm piece having a traveling portion disposed at the tip, and a short arm piece shorter than the long arm piece. You may have a link mechanism comprised including.

In this case, the space occupied by the trajectory of the expansion / contraction arm can be reduced, and the expansion / contraction operation of the expansion / contraction part can be linked to the expansion / contraction operation of the expansion / contraction arm by the link mechanism having a simple structure.

In the case of (8) above, the short arm piece constituting the link mechanism has its base end rotatable to the movable part of the telescopic part, and its tip is rotatable between the tip of the long arm piece and the base end. It is preferably fixed. This is preferable in terms of the linkage between the expansion / contraction operation of the expansion / contraction part and the expansion / contraction operation of the expansion / contraction arm. The short arm piece is preferably provided in the vicinity of the tip of the long arm piece in view of the stability of the expansion / contraction arm.

(9)
In the ultrasonic inspection apparatus of the present invention, the motor is a hollow shaft motor including a hollow rotating member and a non-rotating member surrounding the hollow rotating member, and at least a part of the ultrasonic probe is a hollow rotating member. It is preferable to be disposed in the hollow portion.

This makes it possible to make the size of the axial portion of the ultrasonic inspection apparatus compact.

(10)
In the ultrasonic inspection apparatus according to the present invention described in (1) to (9) above, the expansion / contraction part may include an auxiliary spring that assists the operation of the expansion / contraction arm.

∙ As a result, the operation of the expansion / contraction arm is assisted by the auxiliary spring, so that the expansion / contraction arm operates more smoothly.

(11)
In the ultrasonic inspection apparatus according to the present invention described in (1) to (10) above, the expansion / contraction part may be driven by atmospheric pressure.

In this case, since the medium is air, the danger of contamination, ignition, electric shock, etc. in the pipe is avoided even if the medium leaks.

(12)
In the ultrasonic inspection apparatus of the present invention described in (11) above, the extendable part may be an air cylinder.

This allows the expansion / contraction operation of the expansion / contraction part to be linked to the expansion / contraction operation of the expansion / contraction arm with a simple structure.

(13)
The ultrasonic inspection apparatus of the present invention preferably includes a position marker provided in the motor or the acoustic reflection unit, and a sensor for detecting the position marker.

This makes it possible to accurately determine the circumferential position of the inner wall of the tube to be inspected by ultrasonic waves.

In the above (13), when the motor is a hollow shaft motor, the position marker is provided on the hollow rotating member or the acoustic reflection portion, and the sensor is an ultrasonic probe (continuously fixed to the non-rotating member). It may be fixed continuously. This makes it possible to accurately determine the circumferential position of the inner wall of the tube to be inspected by ultrasonic waves.

<A>
The layer thickness test method for a metal multilayer body of the present invention is a method for testing the layer thickness of a multilayer body including a metal layer and a porous layer provided on the surface of the metal layer. The layer thickness test method includes a transmitting step for applying an ultrasonic wave transmitted in a direction from the porous layer side to the metal layer side through an aqueous medium; and receiving a reflected wave with respect to the ultrasonic propagation time. A waveform acquisition step of acquiring a waveform of the intensity of the reflected wave; at least a peak of the first interface reflected wave first reflected at the boundary surface between the metal layer and the porous layer from the acquired waveform; and the metal layer A determination step of determining a peak of the first outer surface reflected wave first reflected on the surface opposite to the porous layer; and a detection time difference between the peak of the first interface reflected wave and the peak of the first outer surface reflected wave And a thickness calculating step of calculating the thickness of the metal layer based on the above.

This makes it possible to measure the thickness of the metal layer in a nondestructive manner.

<B>
The layer thickness test method for a metal multilayer body of the present invention is a method for testing the layer thickness of a multilayer body including a metal layer and a porous layer provided on the surface of the metal layer. The layer thickness test method includes a transmitting step for applying an ultrasonic wave transmitted in a direction from the porous layer side to the metal layer side through an aqueous medium; and receiving a reflected wave with respect to the ultrasonic propagation time. A waveform acquisition step of acquiring a waveform of the intensity of the reflected wave; and when the acquired waveform is detected as a multiple peak due to n-fold reflection (n is an integer of 2 or more) in the metal layer. A determination step of determining at least two peaks of the external reflection wave reflected by the surface of the metal layer opposite to the porous layer from the waveform; and at least arbitrarily selected from the determined peaks of the external reflection wave A thickness calculating step of calculating the thickness of the metal layer based on the detection time of the two peaks.

The peak of the first interface reflected wave and the peak of the outer surface reflected wave (including the first outer surface reflected wave) are detected in a manner that can be discriminated as a reflected wave. For example, the signal noise ratio (S / N) is It means 2.5 or more, preferably 3 or more.

Porous is a solid material with continuous pores that are connected in three dimensions.
The porous material is caused by the fact that the continuous pores are filled with air with particularly low acoustic impedance (that is, extremely small compared to solids and liquids). Hateful. For this reason, the porous material is not inherently suitable for ultrasonic measurement. In the layer thickness test method of the present invention, an aqueous medium is interposed, the porous layer is impregnated with the aqueous medium, and the continuous pores are filled with water having a higher acoustic impedance (that is, having an acoustic impedance close to a solid). It is. That is, the inside of the continuous pores is replaced with air from water. For this reason, it is conceivable that the ultrasonic impedance is easily transmitted by making the difference in acoustic impedance from the solid constituting the porous material small, and ultrasonic measurement is possible.

<C>
In the layer thickness test method of the present invention, the porous material may be a cement-containing material.
Since the cement-containing material has an acoustic impedance that is particularly close to that of water, the difference in acoustic impedance is reduced by the intervention of the aqueous medium, and ultrasonic measurement becomes easier.

<D>
In the layer thickness test method of this invention, it is preferable that the frequency of the ultrasonic wave transmitted in the transmitting step is 1 MHz or more and 9 MHz or less.

This makes it easy to obtain a resolution for separating and detecting peaks in the waveform of the reflected wave intensity with respect to the ultrasonic propagation time. Therefore, it is easy to acquire the thickness of the metal layer more accurately. Since the ultrasonic wave is easily transmitted through the metal layer, the external surface reflected wave is easily obtained in a highly sensitive state.

<E>
The test target of the layer thickness test method of the present invention may be a composite tube in which a porous layer is lined as a lining layer on the inner peripheral surface of a metal tube. In this case, the ultrasonic wave is transmitted from a probe unit provided inside the composite tube.

The lining layer is a layer which is coated on the surface of a base material (metal in the present invention) relatively thickly to prevent corrosion, abrasion and contamination of the base. The probe unit is a member including at least an ultrasonic probe.
In this case, since the layer thickness test can be performed by inserting the probe portion into the composite pipe filled with water, the excavation work becomes unnecessary particularly when the composite pipe is buried.

<F>
In the transmitting step, ultrasonic waves can be transmitted so as to scan the entire inner circumference of the composite tube while maintaining an angle at which the ultrasonic waves are transmitted perpendicularly to the inner surface of the lining layer.
Note that the distance between the head portion of the probe portion and the inner surface of the lining layer corresponds to the thickness of the intervening aqueous medium. The head portion refers to the outer surface on the ultrasonic wave transmission side in the housing of the ultrasonic probe constituting the probe portion.

Further, the term “perpendicular to the inner surface of the lining layer” does not mean that the angle is strictly 90 degrees with respect to the tangent line of the inner surface of the lining layer, but 85 degrees or more and 95 degrees or less with respect to the tangent line. The angle which forms is also allowed. Further, it is preferable that the allowable range is 88 degrees or more and 92 degrees or less because the echo height can be reduced to about half of the case where the echo height is 90 degrees (specifically, a decrease of 6 dB).

Furthermore, a deviation in the radial direction parallel to the tangent (the tangent to the inner surface of the lining layer on which the ultrasonic wave is incident) from the central axis at the position where the ultrasonic wave is transmitted is also allowed. The allowable range of this deviation depends on the water distance, but is within ± 5 mm in the radial direction from the central axis, preferably within ± 3 mm. Thereby, compared with the case where there is no deviation, the echo height can be reduced to about half (decrease by 6 dB as a specific example).

This makes it possible to test the wall thickness of the entire circumference of the metal tube.

<G>
In the layer thickness test method of the present invention, the cement-containing substance to be tested may be mortar.

Thereby, the present invention can realize high versatility particularly when the test object is a mortar lining pipe.

<H>
In the layer thickness test method of the present invention, the metal layer to be tested may be at least one of cast iron and steel.

Thereby, the present invention can realize high versatility, particularly when the test object is an embedded lining pipe. It is also useful when the test object is a buried lining steel structure such as an underground tank.

(14)
The ultrasonic inspection method of the present invention performs ultrasonic inspection inside the tube using the ultrasonic waves described in (1) to (13) above.
As a result, after being inserted into the tube from a small diameter, the inside of the tube is ultrasonically inspected by expanding and contracting the expansion / contraction arm according to the change in the diameter of the tube inner wall and transmitting ultrasonic waves to the tube inner wall while traveling in the tube. be able to.

(15)
In the above (14), the tube may be a multilayer body including a metal layer and a porous layer provided on the surface of the metal layer. In this case, the ultrasonic wave is transmitted in the direction from the porous layer side to the metal layer side under the condition that the aqueous medium is interposed, and at least the first reflected first at the boundary surface between the metal layer and the porous layer. The thickness of the metal layer is calculated based on the detection time difference between the peak of the interface reflected wave and the peak of the first outer surface reflected wave that is first reflected on the surface of the metal layer opposite to the porous layer.

<I>
A layer thickness test apparatus for a metal multilayer according to another aspect is used in the method according to any one of <A> to <H>, a probe unit for transmitting ultrasonic waves; a head unit of the probe unit; A separation part that separates the surface of the porous layer; a waveform acquisition part that acquires a waveform of the reflected wave intensity with respect to the ultrasonic propagation time; and at least a boundary surface between the metal layer and the porous layer from the acquired waveform A determination unit for determining a peak of the first interface reflected wave reflected first and a peak of the first outer surface reflected wave first reflected on the surface of the metal layer opposite to the porous layer; And a thickness calculator for calculating the thickness of the metal layer based on the difference in detection time between the peak of the first and the peak of the first external reflection wave.

This makes it possible to accurately obtain the thickness of the metal layer in a nondestructive manner.

<J>
A layer thickness test apparatus for a metal multilayer according to still another aspect is used in the method according to any one of <A> to <H>, and a probe unit for transmitting ultrasonic waves; and a head unit of the probe unit A separation part that separates the surface of the porous layer from the surface; a waveform acquisition part that acquires a waveform of the reflected wave intensity with respect to the ultrasonic propagation time; and an n-fold reflection (n is the acquired waveform) in the metal layer A determination unit that determines at least two peaks of externally reflected waves that are surface-reflected on the side opposite to the porous layer of the metal layer from the waveform when detected as multiple peaks by an integer of 2 or more); A wall thickness calculating unit that calculates the wall thickness of the metal layer based on the detection time of at least two peaks arbitrarily selected from the determined peak of the external reflection wave.

<K>
The layer thickness test apparatus for a metal multilayer body of the present invention may include an angle holding unit that holds an angle at which ultrasonic waves are transmitted perpendicularly to the inner surface of the porous layer.

Thereby, the echo peak can be detected with sufficient intensity.
Note that the angle holding unit may be provided separately from the separation unit, or may be provided as one configuration of the separation unit.

<L>
The apparatus for testing a thickness of a metal multilayer body according to the present invention is a metal composite tube in which a porous layer is lined as a cement-containing lining layer on an inner peripheral surface of a metal tube, and a separation portion is a shaft of the metal composite tube. A moving mechanism capable of traveling in the central direction may be included.

This makes it possible to test the wall thickness in the axial direction of the metal tube.

<M>
The apparatus for testing a thickness of a metal multilayer body according to the present invention is a metal composite tube in which a porous layer is lined as a cement-containing lining layer on the inner peripheral surface of a metal tube, and ultrasonic waves are applied to the entire inner periphery of the composite tube. May be configured to be transmitted to scan.

<N>
The apparatus for testing a thickness of a metal multilayer body according to the present invention is a metal composite tube in which a porous layer is lined as a cement-containing lining layer on an inner peripheral surface of a metal tube, and a probe portion is a shaft of the metal composite tube. It may be provided so as to be rotatable inside the metal composite tube with the core as a rotation axis.

This makes it possible to test the wall thickness of the entire circumference of the metal tube. In addition, the layer thickness test apparatus of this invention does not ask | require whether it has the said rotating shaft as a part of mechanical structure. As an example of the case where the layer thickness test apparatus of the present invention does not have the rotating shaft as a part of the mechanical configuration, the separating portion is on the inner periphery of the metal composite tube (that is, the surface of the lining layer is in the circumferential direction). The case where the moving mechanism which can drive along is included is mentioned.

The apparatus for testing a thickness of a metal multilayer body according to the present invention is a metal composite tube in which a porous layer is lined as a cement-containing lining layer on an inner peripheral surface of a metal tube, and a probe portion is a shaft of the metal composite tube. A refracting part that refracts the transmitted ultrasonic wave so as to be incident on the inner surface of the lining layer is provided with the axis of the composite tube as the rotation axis. It may be provided so as to be rotatable.

This can be transmitted to scan the entire inner circumference of the composite tube. Therefore, the thickness of the entire circumference of the metal tube can be tested.

<O>
The layer thickness test apparatus for a metal multilayer body of the present invention may be set so that the ultrasonic frequency is 1 MHz or more and 9 MHz or less.
This makes it easy to obtain a resolution for separating and detecting the peak in the waveform of the reflected wave intensity with respect to the ultrasonic propagation time. Therefore, it is easy to acquire the thickness of the metal layer more accurately. Since the ultrasonic wave is easily transmitted through the metal layer, the external surface reflected wave is easily obtained in a highly sensitive state.

<P>
In the layer thickness test apparatus for a metal multilayer body according to the present invention, the probe portion may include an ultrasonic probe.
This makes it possible to use an ultrasonic probe that is generally used in the water immersion method. The ultrasonic probe is generally an ultrasonic sensor that is housed in a casing by adhering a sound absorbing material and a protective plate to a vibrator having piezoelectric characteristics.

According to the present invention, it is possible to provide an ultrasonic inspection apparatus that can freely expand and contract in a tube and an ultrasonic inspection method using the same. Furthermore, according to the present invention, when the measurement target is a composite layer having a porous layer on the surface of the metal layer, it is possible to provide a method capable of obtaining information on the thickness of the metal layer in a non-destructive manner. .

It is a block diagram of the ultrasonic inspection apparatus concerning a 1st embodiment. It is the typical side sectional view and typical side view at the time of diameter expansion of the ultrasonic inspection device concerning a 1st embodiment. It is a typical front view of the ultrasonic inspection apparatus concerning a 1st embodiment. 1 is a schematic front sectional view of an ultrasonic inspection apparatus according to a first embodiment. It is the typical side sectional view and typical side view at the time of diameter reduction of the ultrasonic inspection device concerning a 1st embodiment. It is a typical sectional side view of the principal part containing the detection part of the ultrasonic inspection apparatus concerning 1st Embodiment. It is a typical exploded view of the principal part of FIG. It is a typical back view of the ultrasonic inspection apparatus concerning 2nd Embodiment. It is a typical sectional side view at the time of the diameter expansion of the principal part containing the expansion / contraction arm of the ultrasonic inspection apparatus concerning 2nd Embodiment. It is a typical sectional side view at the time of the diameter reduction of the principal part containing the expansion / contraction arm of the ultrasonic inspection apparatus concerning 2nd Embodiment. It is a typical front sectional view of an ultrasonic inspection device concerning a 3rd embodiment. It is a typical partial sectional side view of the principal part containing the expansion / contraction arm of the ultrasonic inspection apparatus concerning 3rd Embodiment. It is a typical partial sectional side view at the time of the diameter expansion of the principal part containing the expansion / contraction arm of the ultrasonic inspection apparatus concerning 4th Embodiment. It is a typical partial sectional side view at the time of the diameter reduction of the principal part containing the expansion / contraction arm of the ultrasonic inspection apparatus concerning 4th Embodiment. It is a typical partial sectional side view at the time of the diameter expansion of the principal part containing the expansion / contraction arm of the ultrasonic inspection apparatus concerning 5th Embodiment. It is a typical partial cross section figure of the ultrasonic inspection apparatus concerning 5th Embodiment. It is a typical partial sectional side view at the time of the diameter reduction of the principal part containing the expansion / contraction arm of the ultrasonic inspection apparatus concerning 5th Embodiment. It is a typical partial sectional side view at the time of the diameter expansion of the principal part containing the expansion / contraction arm of the ultrasonic inspection apparatus concerning 6th Embodiment. It is a typical partial sectional side view at the time of the diameter reduction of the principal part containing the expansion / contraction arm of the ultrasonic inspection apparatus concerning 6th Embodiment. It is a typical partial side view of the ultrasonic inspection apparatus concerning 7th Embodiment. It is a typical front view of the ultrasonic inspection apparatus concerning a 7th embodiment. It is a typical external view at the time of diameter expansion of the ultrasonic inspection apparatus concerning 8th Embodiment. It is a typical external view of the principal part containing the cable of the ultrasonic inspection apparatus concerning 8th Embodiment. It is a typical external view at the time of diameter reduction of the ultrasonic inspection apparatus concerning 8th Embodiment. It is a typical back sectional view of the ultrasonic inspection equipment concerning an 8th embodiment. It is a conceptual diagram explaining the aspect in which the ultrasonic inspection apparatus concerning 8th Embodiment changes the direction in a cheese type pipe | tube. It is a schematic diagram which shows an example of the layer thickness test method of this Embodiment. It is a schematic diagram which shows an example of the layer thickness test method of this Embodiment. It is a typical partial enlarged view which shows an example of the layer thickness test method of this Embodiment. It is a typical partial enlarged view which shows an example of the layer thickness test method of this Embodiment. It is a block diagram which shows an example of the principal part of the layer thickness test apparatus of this Embodiment. It is a schematic diagram which shows an example of the detection peak pattern in the layer thickness test method of this Embodiment. It is a schematic diagram which shows the other example of the detection peak pattern in the layer thickness test method of this Embodiment. It is a schematic diagram which shows the further another example of the detection peak pattern in the layer thickness test method of this Embodiment. It is a schematic diagram which shows another example of the layer thickness test method of this Embodiment. 3 is a layer thickness test result obtained in Example 1. 3 is a layer thickness test result obtained in Example 2. 4 is a layer thickness test result obtained in Example 3. 4 is a layer thickness test result obtained in Example 4. 5 is a layer thickness test result obtained in Example 5. It is a layer thickness test result obtained in Example 6. It is a layer thickness test result obtained in Example 7. This is the result obtained in Reference Example 1. 10 is a layer thickness test result obtained in Example 8. 10 is a layer thickness test result obtained in Example 9. It is a layer thickness test result obtained in Example 10. 3 is a layer thickness test result obtained in Example 11. It is a layer thickness test result obtained in Example 12. It is a layer thickness test result obtained in Reference Example 2. It is a layer thickness test result obtained in Example 13. It is a layer thickness test result obtained in Example 14.

100, 100a, ..., 100e, 100i, 100e 'Ultrasonic inspection apparatus 100j, 100k Layer thickness test apparatus (one aspect of ultrasonic inspection apparatus)
121 Stretching Control Unit 150 Waveform Acquisition Unit 160 Determination Unit 170

Thickness Calculation Units

200, 200a,...
200j holding part (one aspect of shaft part)
220, 220a, ..., 220e Connection member 220j Connection ring (one aspect of connection member)
300, 300c, 300d, 300e, 300e 'Air cylinder 311

Rod

321c, 321d Movable

part 321e Piston

350c, 350d, 350e, 350e' Auxiliary springs 400, 400a, ..., 400e, 400i, 400e 'Expanding / contracting arm 400j Spacing part (expanding / contracting) (Implemented with an arm)
411a,..., 411e, 411e 'Main arm piece 412a,..., 412e, 412e'

Link arm piece

500, 500a,..., 500e, 500i, 500e ', 500j Wheel 610 Hollow shaft motor 611 Hollow rotating member 612 Non-rotating member 710 Ultrasonic probe 720 Acoustic reflector 720k Mirror (one aspect of acoustic reflector)
770 Single-turn sensor 771 Position marker 772 Sensor 800, 800i Housing part 900 Lining pipe (one aspect of pipe)
910 Metal pipe 920 Cement containing layer S, Sa, ..., Se Free space O Axis center F Traveling direction W Water Ls Inner peripheral surface (inner wall surface)
Li Interface Lb between cement containing layer and metal tube Outer surface R of metal tube Transmitted wave RI1 First interface reflected wave RB1 First outer surface reflected wave RB2 Second outer surface reflected wave

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same elements are denoted by the same reference numerals, and their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

[First Embodiment-Ultrasonic Inspection Apparatus 100]
FIG. 1 is a block diagram of an ultrasonic inspection apparatus according to the first embodiment.
FIG. 2 is a schematic side cross-sectional view and a schematic side view of the ultrasonic inspection apparatus according to the first embodiment at the time of diameter expansion. In FIG. 2, the ultrasonic inspection apparatus inserted in the tube is shown, and the inner wall surface L of the tube is indicated by a dashed line in the drawing (the same applies to the following drawings). The main part including the expansion / contraction arm in FIG. 2 is shown in the upper half of a cross section taken along line AA of FIG. 4 to be described later, and the lower half is a schematic view corresponding to the appearance of the main part described as the cross-sectional view. Shown in
FIG. 3 is a schematic front view of the ultrasonic inspection apparatus according to the first embodiment. The front means an external appearance when the ultrasonic inspection apparatus is viewed in the axial direction of the tube from the traveling direction side.
FIG. 4 is a schematic front sectional view of the ultrasonic inspection apparatus according to the first embodiment. Specifically, a cross section taken along line BB in FIG. 2 is shown.
FIG. 5 is a schematic cross-sectional side view and a schematic side view of the ultrasonic inspection apparatus according to the first embodiment when the diameter is reduced. FIG. 5 is the same as FIG. 2 except that the enlargement / reduction mode is different.

In the following, for convenience of explanation, the direction of the arrow F (see FIGS. 2 and 5) is the traveling direction, the direction opposite to the arrow F is the retreating direction, and the axis O of the inner wall surface L (see FIGS. 3 and 4). ) As the axis, and the radial direction of the inner wall surface L may be referred to as the radial direction.

[Configuration overview]
As shown in FIG. 1, the ultrasonic inspection apparatus 100 according to the present embodiment includes an internal movement unit 110 and an external operation unit 120. The internal movement unit 110 and the external operation unit 120 are physically and electrically connected by a cable 130.

The internal moving part 110 is a part that is inserted into the pipe and travels in the axial direction of the pipe, and includes a cylindrical part (shaft part) 200, an air cylinder 300, an expansion / contraction arm 400, and a wheel 500. In addition, the internal moving unit 110 includes a hollow shaft motor 610, a direction changing unit 620, and a detecting unit 700. The internal movement unit 110 will be described in detail with reference to FIGS. 2 to 5, and the detection unit 700 will be described in detail with reference to FIGS. 2, 3, 6, and 7. In these drawings, the illustration of the cable 130 connected to the internal moving unit 110 is omitted.

The external operation unit 120 is a part that is operated outside the pipe, and includes an input / output unit such as an expansion / contraction control unit 121, a motor control unit 122, a direction control unit 123, and a detection condition control unit 124, a detection information analysis unit 125, and an output. Part 126.

The expansion / contraction control unit 121 controls expansion / contraction of the air cylinder 300. As a specific example, a sequencer for controlling a solenoid valve (described later) which is one of the components constituting the air cylinder 300 can be cited. The motor control unit 122 controls the traveling speed of the wheels 500. The motor control unit 122 controls the hollow shaft motor 610. The direction control unit 123 converts the traveling direction of the wheel 500. The detection condition control unit 124 controls the detection unit 700 such as control of input information such as measurement conditions and feedback control based on output information such as measurement results. The detection information analysis unit 125 analyzes output information from the detection unit 700. The output unit 126 outputs information output by the detection unit 700.

[Cylinder part]
As shown in FIG.2 and FIG.4, the internal movement part 110 has the cylinder part 200 in the front view center. The cylindrical portion 200 extends in the axial direction of the inner wall surface L of the tube, and includes a shaft housing portion 210 and a connecting member 220 provided on the outer peripheral surface of the shaft housing portion 210.

A desired member can be accommodated in the shaft housing part 210. For example, related parts (described later) of the air cylinder 300 can be accommodated. In addition, the direction changer 620 and the cable 130 shown in FIG. 1 can be accommodated.

The connecting member 220 connects the cylindrical portion 200 and other members. In this embodiment, the air cylinder 300 and the expansion / contraction arm 400 are connected. The connecting member 220 is provided in a manner corresponding to the expansion / contraction mechanism of the expansion / contraction arm 400.

In the present embodiment, the connecting member 220 is fixed to the sliding ring 221 provided so as to be slidable in the axial direction on the outer peripheral surface of the shaft housing portion 210 and the outer peripheral surface of the shaft housing portion 210. Fixing rings 222, 223, and 225. In the axial direction, a fixing ring 223, a fixing ring 225, a sliding ring 221 and a fixing ring 222 are provided in this order from the traveling direction F side.

The sliding ring 221 is pivotally attached to the base of the expansion / contraction arm 400. Thereby, the base part of the expansion-contraction arm 400 is connected in the state which can rotate freely and can move to an axial direction.
The fixing rings 222 and 223 also pivotally attach to the base of the expansion / contraction arm 400. Thereby, the base part of the expansion-contraction arm 400 is connected in the state fixed rotatably.
On the other hand, the fixing ring 225 fixes the air cylinder 300 so as to hold it.

[Air cylinder]
The air cylinder 300 is an actuator that is driven using the pressure of air. Accordingly, the piston 310, the cylinder 320, and other related parts (not shown) are included. Related parts include parts necessary for air circulation, specifically, air piping and a compressed air source. Other related parts include parts necessary for operation, specifically, a speed controller that adjusts the speed, a sensor that detects the piston position, and a solenoid valve that switches the direction of air.

The air cylinder 300 is arranged so as to extend in the axial direction as shown in FIG. Thereby, the expansion / contraction direction of the air cylinder 300 becomes the axial direction. A portion of the cylinder 320 is fixed to the fixing ring 225, while the rod 311 of the piston 310 of the air cylinder 300 is fixed to the sliding ring 221. Therefore, the sliding ring 221 slides in the axial direction by the expansion / contraction operation of the air cylinder 300, and thereby the expansion / contraction arm 400 connected to the sliding ring 221 can be operated as will be described in detail later.

[Expansion and contraction arm and wheel]
As shown in FIGS. 2 and 4, the expansion / contraction arm 400 is connected to the connecting member 220 of the cylindrical portion 200, thereby projecting in the radial direction around the axial center of the cylindrical portion 200, that is, in the radial direction of the tube. Established. A wheel 500 is provided at the tip of the expansion / contraction arm 400, that is, the portion of the expansion / contraction arm 400 that is farthest from the cylindrical portion 200. In the present embodiment, three sets of the expansion / contraction arm 400 and the wheel 500 are provided so as to be equally spaced around the axis.

The expansion / contraction arm 400 includes a main arm piece 411, a link arm piece 412, a sub arm piece 413, and a synchronization arm piece 414. Together with the connecting member 220 and the air cylinder 300, they constitute a link mechanism that links the expansion / contraction operation of the air cylinder 300 with the expansion / contraction operation of the expansion / contraction arm 400.

As shown in FIG. 4, the main arm piece 411, the link arm piece 412, the sub arm piece 413, and the synchronization arm piece 414 are provided in pairs at both ends of the axle 500 so as to hold the axle of the wheel 500. A free space S is formed between the arm pieces.

As shown in FIG. 2, the main arm piece 411 can be rotated so that the angle with respect to the shaft center changes with the base end portion being pivotally attached to the sliding ring 221. Since the distal end portion of the main arm piece 411 is connected to the wheel 500 via the synchronous arm piece 414 as will be described later, the amount of separation of the wheel 500 from the cylinder portion 200 is physically defined by the rotation operation.

The base arm position of the main arm piece 411 can move in the axial direction as the sliding ring 221 moves in the axial direction. The slide ring 221 fixes the rod 311 of the air cylinder 300 as described above. That is, the base end position of the main arm piece 411 moves with the expansion / contraction operation of the air cylinder 300.

Further, the distal end portion of the link arm piece 412 is rotatably fixed between the distal end portion and the proximal end portion of the main arm piece 411. The link arm piece 412 is pivotally attached to the fixing ring 222 at the base end portion on the retreat direction side with respect to the fixing position of the tip end portion. Accordingly, the link arm piece 412 rotates in the direction opposite to the main arm piece 411 around the axis-attached portion according to the change in the relative position with the base end portion of the main arm piece 411, and the distal end of the main arm piece 411 The part is operated so as to be close to or away from the cylindrical part 200.

The sub arm piece 413 has the same shape and size as the main arm piece 411, and the base end portion is pivotally attached to the fixing ring 223, so that the sub arm piece 413 can perform the same rotation operation as the main arm piece 411. Further, the distal end portion of the sub arm piece 413 is connected to a synchronous arm piece 414 to which the distal end portion of the main arm piece 411 is rotatably fixed so as to be rotatable and slidable in the axial direction. Therefore, the sub arm piece 413 rotates by the synchronization arm piece 414 in synchronization with the rotation operation of the main arm piece 411.

Furthermore, since the connecting position moves in the axial direction along with the rotational operation at the tip of the sub arm piece 413, the synchronous arm piece 414 maintains a posture substantially parallel to the axial center throughout the operation. Since the wheels 500 are provided at both ends of the synchronization arm piece 414 in the axial center direction, both wheels 500 can reliably contact the inner wall surface L parallel to the axial center.
Other members (not shown) related to the wheel 500, such as a driving device and a suspension, may be provided.

[Scale operation]
As shown in FIG. 2, when the diameter is expanded, the sliding ring 221 is the same as the arrow E as the expansion / contraction control unit 121 (see FIG. 1) is operated to extend the air cylinder 300 in the direction of the arrow E. By moving in the direction, the base end position of the main arm piece 411 also moves in the same direction as the arrow E. As a result, the space between the base end of the main arm piece 411 and the base end of the link arm piece 412 is narrowed, so that the link arm piece 412 raises its tip end in a direction away from the tube portion 200 and the main arm piece 411. Is raised in a direction away from the cylindrical portion 200. The main arm piece 411 is operated so that the sub arm piece 413 similarly occurs via the synchronous arm piece 414. As a result, the expansion / contraction arm 400 is expanded in the direction of the arrow SU, and a load is applied to stretch the wheels 500 provided at both ends of the synchronization arm piece 414 with respect to the inner wall surface L.

In this case, since the air cylinder 300 is synchronously extended in all the expansion / contraction arms 400 provided to the cylinder portion 200 by the operation of the expansion / contraction control unit 121 (see FIG. 1), the degree of expansion in all the expansion / contraction arms 400 And the expansion timing becomes substantially equal. By such an expansion operation of the expansion / contraction arm 400, as shown in FIG. 4, the center of the cylindrical portion 200 is aligned so as to substantially coincide with the axis of the inner wall surface L.

On the contrary, as shown in FIG. 5, when the diameter is reduced (when the diameter is reduced to the minimum), the expansion / contraction control unit 121 (see FIG. 1) is operated to reduce the air cylinder 300 in the direction of arrow C. Accordingly, the sliding ring 221 moves in the same direction as the arrow C, so that the base end position of the main arm piece 411 also moves in the same direction as the arrow C. As a result, the space between the base end portion of the main arm piece 411 and the base end portion of the link arm piece 412 expands, so that the link arm piece 412 tilts the tip end portion in the direction close to the cylindrical portion 200 and the main arm piece 411. Is tilted in the direction of approaching the tube part 200. The operation of the main arm piece 411 causes the sub arm piece 413 to be similarly moved down via the synchronous arm piece 414. As a result, the expansion / contraction arm 400 is contracted in the direction of the arrow SD. Also in this case, the expansion / contraction arm 400 applies a load that causes the wheels 500 provided at both ends of the synchronization arm piece 414 to be stretched against the inner wall surface L.

In this case, since the air cylinders 300 are synchronously contracted in all the expansion / contraction arms 400 provided for the cylindrical portion 200 by the operation of the expansion / contraction control unit 121 (see FIG. 1), The timing of reduction becomes substantially equal. By such a reduction operation of the expansion / contraction arm 400, the axis of the cylindrical portion 200 is aligned so as to substantially coincide with the axis of the inner wall surface L.

Further, when the expansion / contraction arm 400 is reduced to the minimum as shown in FIG. 5, a part of the air cylinder 300 is accommodated in the free space S (see FIG. 4) formed in the expansion / contraction arm 400. That is, the presence of the air cylinder 300 does not hinder the diameter reduction. For this reason, when the expansion / contraction arm 400 is reduced to the minimum, the size of the ultrasonic inspection apparatus 100 in the radial direction can be made compact.

Such expansion / contraction of the expansion / contraction arm 400 is performed by remotely operating the expansion / contraction operation of the air cylinder 300 by the expansion / contraction control unit 121 (see FIG. 1) of the external operation unit 120. Is free. Thereby, even in a portion where the change in the diameter of the inner wall surface L is large, the diameter can be positively reduced and expanded according to the change in the diameter of the inner wall surface L. Furthermore, the direction change in cheese-shaped piping is also facilitated.

[Motor and detector]
As shown in FIG. 2, a hollow shaft motor 610 housed in a housing 800 and a detection unit 700 are disposed at the end of the cylindrical part 200 on the traveling direction F side. The hollow shaft motor 610 includes a rotating hollow rotating member 611 and a non-rotating non-rotating member 612, and the detection unit 700 includes an ultrasonic probe 710 and an acoustic reflection unit 720.

As shown in FIG. 3, the hollow rotating member 611 has a circular pipe shape with a through hole 615 for securing a hollow portion, and is disposed coaxially with the axis O of the cylindrical portion 200. The non-rotating member 612 has a substantially square block shape with a through hole corresponding to the outer surface of the hollow rotating member 611, and the hollow rotating member 611 can be rotated by passing the hollow rotating member 611 through the through hole. Go to. Further, fixing screw holes are recessed in the vicinity of the four corners of the substantially square of the non-rotating member 612.

As shown in FIGS. 6 and 7, the housing portion 800 that accommodates the hollow shaft motor 610 includes a casing member 810 that opens on the retracting direction side, and a casing cover member 820 that closely fits the opening portion. A close fitting portion between the casing member 810 and the casing cover member 820 is sealed with a gasket. The casing member 810 and the casing cover member 820 have a through hole 813 and a through hole 822 that are coaxial with the axis O, respectively. The casing cover member 820 is provided with a cable hole 826 that allows the motor cable 136 of the hollow shaft motor 610 to pass therethrough, and the motor cable 136 is wired from the inside of the housing portion 800 to the outside. Further, the casing cover member 820 has a screw hole at a position corresponding to a fixing screw hole provided in the non-rotating member 612 of the hollow shaft motor 610, and the non-rotating member 612 is fixed by screwing. (Refer to the lower half of FIG. 6).

A probe fixing member 750 is further screwed and fixed to the casing cover member 820 fixed to the non-rotating member 612 in this way (see the upper half of FIG. 6). As shown in FIGS. 6 and 7, the probe fixing member 750 is provided with a through hole 755 that is coaxial with the axis O and has a diameter that allows the ultrasonic probe 710 to be fitted therein. The ultrasonic probe 710 is fixed by fitting the ultrasonic probe 710 into the screw. As a result, the ultrasonic probe 710 is fixed to the non-rotating member 612 of the hollow shaft motor 610 via the probe fixing member 750 and the casing cover member 820. In this case, as shown in FIG. 6, the ultrasonic wave propagation part 712 of the ultrasonic probe 710 also penetrates through the through hole 822 of the casing cover member 820, and the end on the traveling direction side is a hollow shaft in the housing part 800. The motor 610 is inserted until it reaches the inside of the through hole 615 (inside the hollow portion). Thereby, the length of the ultrasonic inspection apparatus in the axis O direction can be shortened.
Note that the probe cable 137 of the ultrasonic probe 710 is wired into the shaft housing 210 (see FIG. 2).

Since the ultrasonic probe 710 fixed as described above is coaxial with the axis O, the ultrasonic wave transmitted from the transmitting unit 711 and propagated in the ultrasonic propagating unit 712 is transmitted to the axis O. It is transmitted in the traveling direction so that the sound axes coincide.
On the other hand, as shown in FIG. 6, an acoustic reflection unit 720 for changing the propagation direction of the transmitted ultrasonic wave is provided on the traveling direction side of the fixed ultrasonic probe 710 in a rotatable manner. . As shown in FIGS. 6 and 7, the acoustic reflection unit 720 includes a reflection member 721 and a rotation holder 724 to which the reflection member 721 is attached.

The rotating holder 724 is a cylindrical member having a large-diameter cylindrical portion 725 on the traveling direction side into which the reflecting member 721 is inserted and a small-diameter cylindrical portion 726 on the retracting direction side fixed to the hollow rotating member 611 (FIG. 7). reference). As shown in FIG. 6, the rotation holder 724 passes through the through hole 813 of the casing member 810 and is inserted into the housing portion 800. It is inserted. In this case, the insertion amount of the rotating holder 724 is such that the locking surface 729 formed at the boundary between the large diameter cylindrical portion 725 and the small diameter cylindrical portion 726 contacts and locks the end surface on the traveling direction side of the hollow rotating member 611. Is determined by As a result, the end of the small-diameter tubular portion 726 on the retracting direction side is loosely inserted into the through hole of the casing cover member 820, and the end face of the end and the contact surface 751 of the probe fixing member 750 are inserted. A clearance (for example, a gap of 0.1 mm or more and 0.5 mm or less) is generated between the two. At the same time, the ultrasonic wave propagation portion 712 of the ultrasonic probe 710 is loosely inserted into the small diameter cylindrical portion 726.

As shown in FIG. 6, the rotation holder 724 is fixed to the hollow rotation member 611 by the small diameter cylindrical portion 726 being fitted into the through hole 615 of the hollow rotation member 611, so that the rotation of the hollow rotation member 611 is performed. It can be rotated integrally with driving.

On the other hand, as shown in FIG. 6, a loose groove portion between the large-diameter cylindrical portion 725 of the rotary holder 724 and the through hole 813 of the casing member 810 has a packing groove 811 (see FIG. 7) formed in the through hole 813. In the loose insertion portion between the small diameter cylindrical portion 726 of the rotary holder 724 and the through hole 822 of the casing cover member 820, the packing is fitted in the packing groove 824 formed in the through hole 822. . The packing may be any sealing material for rotational movement, and an oil seal is an example.
Further, in the loose insertion portion between the small diameter cylindrical portion 726 and the ultrasonic propagation portion 712 of the rotary holder 724, a clearance (for example, between the inner wall 728 of the small diameter cylindrical portion 726 and the outer surface of the ultrasonic propagation portion 712). , A gap of 0.1 mm to 0.5 mm is generated.

Thus, by providing the rotation holder 724 so as not to be fixed to a member other than the hollow rotating member 611, the housing portion 800 and the ultrasonic probe 710 can be rotated freely while being rotatable integrally with the hollow rotating member 611. The non-rotating state can be maintained together with the non-rotating member 612 without transmitting the rotational driving of the member 611.

The reflection member 721 that is fixedly inserted and fixed to the opening end of the large-diameter cylindrical portion 725 of the rotary holder 724 has an inclined surface 723 that can reflect ultrasonic waves on the regression direction side. Specifically, the inclined surface 723 is formed so as to form 45 degrees with respect to the axis O in a side view, and is transmitted from the ultrasonic probe 710 in the direction of the axis O within the large-diameter cylindrical portion 725. The reflected ultrasonic wave is reflected on the axis O and its propagation direction is changed vertically. Note that the material of the reflecting member 721 on the inclined surface 723 has a large acoustic impedance value relative to the acoustic impedance value of the ultrasonic propagation medium (water in this embodiment) from the ultrasonic probe 710. It is comprised from the metal material, resin material, ceramic material, etc. which have a difference.
An exit hole 727 serving as an exit to the outside of the ultrasonic wave whose propagation direction is changed by the inclined surface 723 is provided on a side surface of the large diameter cylindrical portion 725 of the rotary holder 724.

As a result, as indicated by the dotted line in FIG. 2, the ultrasonic wave transmitted from the ultrasonic probe 710 is changed in propagation direction by the inclined surface 723, propagates outside through the exit hole 727, and passes through the tube. Incident perpendicularly to the inner wall L.
Further, when the rotary holder 724 rotates about the axis O by the rotation of the hollow shaft motor 610, the inclined surface 723 of the reflecting member 721 also rotates integrally. Thereby, the incident position can be rotated and moved along the circumferential direction of the tube while maintaining the incident angle to the inner wall L of the tube. Therefore, the inner wall surface L in the circumferential direction of the tube can be scanned evenly.

Furthermore, as shown in FIG. 6, a one-turn sensor 770 is provided inside the housing unit 800. The single rotation sensor 770 includes a position marker 771 fixed to the hollow rotation member 611 and a sensor 772 fixed to the casing cover member 820. The position marker 771 is detected by a sensor 772 such as a permanent magnet, and rotates together with the hollow rotating member 611. On the other hand, the sensor 772 is a sensor selected according to the characteristics of the position marker 771 such as a Hall element, and the non-rotating state is maintained together with the non-rotating member 612.

Therefore, the sensor 772 detects when the position of the rotating position marker 771 coincides with the position shown in the figure, thereby detecting the time for one rotation of the hollow rotating member 611. A more detailed position marker position can be derived from the detection timing (period T) of the sensor 772 and the rotation time (<T) of the position marker 771.

[Second Embodiment-Ultrasonic Inspection Apparatus 100a]
FIG. 8 is a schematic rear view of the ultrasonic inspection apparatus according to the second embodiment. The back surface means an external appearance when the device is viewed from the regression direction side in the axial direction of the tube. FIG. 9 is a schematic partial cross-sectional view of the ultrasonic inspection apparatus according to the second embodiment at the time of diameter expansion. 9 schematically shows a cross section taken along the line DD of FIG. 8, and the hollow shaft motor 610, the detection unit 700, and the housing unit 800 are omitted because they are the same as those in the first embodiment. FIG. 10 is a schematic partial side sectional view of the ultrasonic inspection apparatus according to the second embodiment when the diameter is reduced. FIG. 10 is displayed in the same manner as FIG. 9 except that the enlargement / reduction mode is different.

In the second embodiment, portions that are different from the first embodiment will be mainly described, and description of similar portions will be omitted.
The internal movement part 110a of the ultrasonic inspection apparatus 100a shown in FIGS. 8 to 10 includes an expansion / contraction arm 400a having a link mechanism different from that of the first embodiment, and an auxiliary wheel 510a.

[Connecting members]
The connecting member 220a is provided in a manner corresponding to the expansion / contraction arm 400a. In the present embodiment, the connecting member 220a includes the sliding ring 221a provided so as to be slidable in the axial direction on the outer peripheral surface of the shaft housing portion 210, and the outer peripheral surface of the shaft housing portion 210 of the cylindrical portion 200a. And fixing

rings

224a and 225a. In the axial direction, a fixing ring 224a, a sliding ring 221a, and a fixing ring 225a are provided in this order from the traveling direction F side.

[Air cylinder]
The air cylinder 300 is fixed to the fixing ring 225a, and the rod 311 is fixed to the sliding ring 221a. Therefore, the sliding ring 221a slides in the axial direction by the expansion / contraction operation of the air cylinder 300, and thereby the expansion / contraction arm 400a connected to the sliding ring 221a can be operated as will be described in detail later.

[Expansion and contraction arm]
The expansion / contraction arm 400a includes a main arm piece 411a and a link arm piece 412a having a shorter length than the main arm piece 411a. Together with the connecting member 220a and the air cylinder 300, these constitute a link mechanism that links the expansion / contraction operation of the air cylinder 300 with the expansion / contraction operation of the expansion / contraction arm 400a.

As shown in FIG. 8, since the main arm piece 411a and the link arm piece 412a are provided in pairs at both ends of the axle 500 so as to hold the axle of the wheel 500a, there is free between the pair of arm pieces. A space Sa is formed.

As shown in FIG. 9, the main arm piece 411a can be rotated so that the angle θ with respect to the shaft center changes with the base end portion being pivotally attached to the fixing ring 224a. Since the wheel 500a is connected to the tip of the main arm piece 411a, the amount of separation of the wheel 500a from the cylindrical portion 200a is physically defined by the rotation operation. The angle θ should not exceed 90 degrees. Furthermore, it may be 60 degrees or less or 45 degrees or less from the viewpoint of stability of the ultrasonic inspection apparatus 100a when the diameter of the expansion / contraction arm 400a is expanded most.

Further, the distal end portion of the link arm piece 412a is rotatably fixed between the distal end portion and the proximal end portion of the main arm piece 411a. The link arm piece 412a is pivotally attached to the sliding ring 221a at the base end portion on the traveling direction F side from the fixed position of the tip end portion. As a result, the rotation can be performed so that the angle with respect to the axis changes around the axis-attached portion, and the base end position can move in the axis direction as the sliding ring 221a moves in the axis direction. Accordingly, the link arm piece 412a rotates in the same direction as the main arm piece 411 around the pivoted portion in accordance with a change in the relative position with the base end of the main arm piece 411a, and the tip of the main arm piece 411a. The part is operated so as to be close to or away from the cylindrical part 200a.

The main arm piece 411a has a pair of auxiliary wheels 510a. The pair of auxiliary wheels 510a is pivotally attached between the base end portion and the tip end portion, in the vicinity of the base end portion in the present embodiment. The auxiliary wheel 510a has a wheel shaft that can slide in the short direction of the main arm piece 411a, and is biased in a direction that is exposed from the main arm piece 411a to the inner wall surface L side in a side view. The wheel axle slides against the urging force when the tip of the main arm piece 411a is close to the cylindrical portion 200a and the auxiliary wheel 510a contacts the inner wall surface L.

[Scale operation]
As shown in FIG. 9, when the diameter is expanded, the sliding ring 221a is moved in the same direction as the arrow C as the expansion / contraction control unit 121 (see FIG. 1) is operated to contract the air cylinder 300 in the arrow C direction. The base end position of the link arm piece 412a also moves in the same direction as the arrow C. As a result, the space between the base end portion of the link arm piece 412a and the base end portion of the main arm piece 411a widens, so that the link arm piece 412a raises the tip end portion in a direction away from the cylindrical portion 200a and the main arm piece 411a. Is raised in a direction away from the cylindrical portion 200a. As a result, the expansion / contraction arm 400a is expanded in the direction of the arrow SU, and a load is applied to stretch the wheel 500a provided at the tip of the main arm piece 411a against the inner wall surface L.

In this case, since the air cylinder 300 is synchronously contracted in all of the expansion / contraction arms 400a provided for the cylindrical portion 200a by the operation of the expansion / contraction control unit 121 (see FIG. 1), the degree of expansion in all the expansion / contraction arms 400a. And the expansion timing becomes substantially equal. By such an expansion operation of the expansion / contraction arm 400a, the axis of the cylindrical portion 200a is aligned so as to substantially coincide with the axis of the inner wall surface L.

On the contrary, as shown in FIG. 10, when the diameter is reduced (when the diameter is reduced to the minimum), the expansion / contraction control unit 121 (see FIG. 1) is operated to extend the air cylinder 300 in the direction of arrow E. Accordingly, the sliding ring 221a moves in the same direction as the arrow E, so that the base end position of the link arm piece 412a also moves in the same direction as the arrow E. As a result, the space between the base end portion of the link arm piece 412a and the base end portion of the main arm piece 411a is narrowed, so that the link arm piece 412a tilts the tip end portion in the direction close to the cylindrical portion 200a and the main arm piece 411a. Is tilted in a direction approaching the tube portion 200a. As a result, the expansion / contraction arm 400a is contracted in the direction of the arrow SD. In this case as well, the expansion / contraction arm 400a applies a load that stretches the wheel 500a against the inner wall surface L.

In this case, since the air cylinder 300 is synchronously extended in all the expansion / contraction arms 400a provided to the cylindrical portion 200a by the operation of the expansion / contraction control unit 121 (see FIG. 1), the degree of reduction and The timing of reduction becomes substantially equal. Also by such a reduction operation of the expansion / contraction arm 400a, the axis of the cylindrical portion 200a is aligned so as to substantially coincide with the axis of the inner wall surface L.

Further, when the expansion / contraction arm 400a is reduced to the minimum as shown in FIG. 10, the arm pieces constituting the expansion / contraction arm 400a are folded until they are parallel to the axis. At this time, the auxiliary wheel 510a provided in the vicinity of the base end portion of the main arm piece 411a comes into contact with the inner wall surface L, so that the ultrasonic inspection apparatus 100a is balanced. Further, the air cylinder 300 is accommodated in a free space Sa (see FIG. 8) formed in the expansion / contraction arm 400a. That is, the presence of the air cylinder 300 does not hinder the diameter reduction. For this reason, when the expansion / contraction arm 400a is reduced to the minimum, the size of the ultrasonic inspection apparatus 100a in the radial direction can be made compact.

[Third Embodiment-Ultrasonic Inspection Apparatus 100b]
FIG. 11 is a schematic front view of an ultrasonic inspection apparatus according to the third embodiment. FIG. 12 is a schematic sectional side view of an ultrasonic inspection apparatus according to the third embodiment. FIG. 12 shows a cross section taken along line EE of FIG.

The internal movement part 110b of the ultrasonic inspection apparatus 100b shown in FIGS. 11 and 12 has the same expansion / contraction arm 400b and wheel 500b as the expansion / contraction arm 400a and the wheel 500a of the second embodiment except that the auxiliary wheel 510a is not provided. . The expansion / contraction arm 400b is projecting radially from the axial center of the cylindrical portion 200b by being connected to the connecting member 220b of the cylindrical portion 200b. A wheel 500b is provided at the distal end of the expansion / contraction arm 400b, that is, the portion of the expansion / contraction arm 400b that is farthest from the cylindrical portion 200b.

In the present embodiment, as shown in FIG. 11, six sets of expansion / contraction arms 400b and wheels 500b are provided at equal intervals around the axis. As shown in FIG. 12, adjacent expansion / contraction arms 400b are arranged so that the directions in the axial direction are staggered. For this reason, the wheel 500b is always in contact with the inner wall surface L on both the traveling direction F side and the facing direction side. Therefore, the ultrasonic inspection apparatus 100b can always be stably held in the tube.

The expansion / contraction arm 400b includes a main arm piece 411b and a link arm piece 412b having a shorter length than the main arm piece 411b, and these, together with the connecting member 220b and the air cylinder 300, are combined with the air cylinder 300. It is the same as that in the internal movement part 110a of 2nd Embodiment to comprise the link mechanism which links this expansion-contraction operation | movement with expansion / contraction operation | movement of the expansion / contraction arm 400b. Accordingly, the operation and function of the expansion / contraction arm 400b are the same as those in the internal movement unit 110a of the second embodiment.

[Fourth Embodiment-Ultrasonic Inspection Apparatus 100c]
FIG. 13 is a schematic partial cross-sectional view of the ultrasonic inspection apparatus according to the fourth embodiment at the time of diameter expansion. FIG. 14 is a schematic partial side sectional view of the ultrasonic inspection apparatus according to the fourth embodiment when the diameter is reduced.

13 and 14 is a modification of the ultrasonic inspection apparatus 100b according to the third embodiment. Specifically, in the internal movement unit 110c, the expansion / contraction arm 400c, its constituent arm pieces (the main arm 411c and the link arm 412c), the wheel 500c, and the free space Sc are respectively an ultrasonic inspection apparatus 100b according to the third embodiment. This is the same as the expansion / contraction arm 400b and its constituent arm pieces (the main arm 411b and the link arm 412b), the wheel 500b, and the free space Sb. On the other hand, instead of the shaft housing part 210 and the air cylinder 300 of the ultrasonic inspection apparatus 100b according to the third embodiment, there are a shaft housing part 210c and an air cylinder 300c, respectively.

In the present embodiment, as the connecting member 220c, a fixing ring 224c, a sliding ring 221c, a sliding ring 226c, and a fixing ring 227c are provided from the traveling direction side. The fixing rings 224c and 227c are fixed to the shaft housing portion 210c, and the sliding

rings

221c and 226c are provided so as to be slidable on the surface of the shaft housing portion 210c in the axial direction. The shaft housing portion 210c constitutes a part of an air cylinder 300c (air tank 330c) described later.

The base end portion of the main arm piece 411c is pivotally attached to the fixing ring 224c. The base end portion of the link arm piece 412c is pivotally attached to a sliding ring 221c that is provided on the retraction direction side of the fixed ring 224c and can be manually operated in the axial direction. Each of the sliding ring 221c and the fixed ring 224c has a shaft attachment portion of a link arm piece 412c and a main arm piece 411c, and both constitute a part (following portion 340c) of an air cylinder 300c described later. Is formed.

[Air cylinder]
The air cylinder 300c includes an air tank 330c, a follower 340c, and an auxiliary spring 350c.
The air tank 330c is used to send and discharge air serving as an operation source of the expansion / contraction arm 400c, and is configured by the shaft housing portion 210c. An air tube (not shown) for sending and discharging air is connected to the air tank 330c.

The follower 340c constitutes an expansion / contraction mechanism so that the operation follows as air is fed into the air tank 330c and discharged from the air tank 330c. That is, the expansion / contraction operation of the air cylinder 300c is caused by the expansion / contraction operation of the follower 340.

The follower 340c includes a sliding ring 221c and a fixed ring 224c. More specifically, the sliding ring 221c has a housing portion that opens in the traveling direction F side, the fixing ring 224c has an extending portion that extends in the backward direction, and the inner peripheral side surface of the sliding ring 221c. The outer peripheral surface of the extending portion of the fixing ring 224c is slidably adhered to the extension ring 224c to constitute an expansion / contraction mechanism. Furthermore, the space AR in the housing portion and the space in the air tank 330c communicate with each other through a communication hole provided in the air tank 300c. As a result, the air supply to the air tank 330c and the air discharge operation from the air tank 330c change the volume of the space AR in the housing part and cause the follow-up part 340c to expand and contract.

Hereinafter, for the purpose of explaining expansion and contraction of the air cylinder 300c, the fixed ring 224c may be referred to as a fixed portion 324c of the air cylinder 300c, and the sliding ring 221c may be referred to as a movable portion 321c of the air cylinder 300c.

The auxiliary spring 350c is provided on the retreating direction side of the sliding ring 221c so as to extend in the axial direction, and one is fixed to the sliding ring 226c and the other is fixed to the fixing ring 227c. Further, since the sliding ring 221c and the sliding ring 226c are fixed to each other, the auxiliary spring 350c moves as the sliding ring 221c moves.

[Scale operation]
As shown in FIG. 13, during the diameter expansion, the expansion / contraction control unit 121 (see FIG. 1) is operated to send air into the air tank 330c of the air cylinder 300c. Thereby, the sent air moves in the direction of the arrow FL in the drawing in the communication hole of the air tank 330c, and the air flows into the space AR. Accordingly, the movable portion 321c moves together with the sliding ring 226c, so that the base end position of the link arm piece 412c moves in the retreat direction. As a result, the space between the link arm piece 412c and the main arm piece 411c is widened, so that the link arm piece 412c raises its distal end portion in a direction away from the cylindrical portion 200c and the main arm piece 411c is separated from the cylindrical portion 200c. Wake up. As a result, the expansion / contraction arm 400c is expanded in the direction of the arrow SU, and a load is applied to stretch the wheel 500c provided at the tip of the main arm piece 411c against the inner wall surface L.
On the other hand, the auxiliary spring 350c contracts with the movement of the sliding ring 226c.
It is the same as that of the above-mentioned embodiment that it is diameter-expanded in the state aligned so that the axial center of the cylinder part 200c may correspond with the axial center of the inner wall surface L substantially.

On the contrary, as shown in FIG. 14, when the diameter is reduced (when the diameter is reduced to the minimum), the expansion / contraction control unit 121 (see FIG. 1) is operated to discharge air from the air tank 330c of the air cylinder 300c. Thereby, the air in the space AR moves in the communication hole of the air tank 330c in the direction of the arrow FL in the figure, and the air is discharged from the space AR. Accordingly, since the movable portion 321c moves together with the sliding ring 226c, the base end position of the link arm piece 412c moves in the traveling direction. At the same time, a force is applied to the movable portion 321c to return the auxiliary spring 350c that has contracted due to the diameter expansion, so that the sliding operation occurs smoothly.

As a result, the space between the link arm piece 412c and the main arm piece 411c is narrowed, so that the link arm piece 412c tilts the tip portion in a direction close to the cylindrical portion 200c and the main arm piece 411c approaches the cylindrical portion 200c. knock down. As a result, the expansion / contraction arm 400c is reduced in the direction of the arrow SD. Also in this case, the expansion / contraction arm 400c gives a load that stretches the wheel 500c against the inner wall surface L.
Similar to the above-described embodiment, the diameter is reduced in a state in which the axis of the cylindrical portion 200c is aligned so as to substantially coincide with the axis of the inner wall surface L.

Further, when the expansion / contraction arm 400c is reduced to the minimum as shown in FIG. 14, the auxiliary spring 350c is accommodated in the free space Sc formed in the expansion / contraction arm 400c. That is, the presence of the auxiliary spring 350c does not hinder the diameter reduction. For this reason, when the expansion / contraction arm 400c is reduced to the minimum, the size of the ultrasonic inspection apparatus 100c in the radial direction can be made compact.

In the present embodiment, the auxiliary spring 350c is disposed on the side opposite to the fixed ring 224c with respect to the sliding ring 221c in the axial direction. However, the present invention is not limited to this embodiment. . For example, the auxiliary spring 350c may be disposed in a state where both ends are fixed between the fixed ring 224c and the sliding ring 221c. In this case, when the diameter is expanded, the auxiliary spring is extended, and when the diameter is reduced, the returning operation of the expansion / contraction arm 400c can be assisted by the return force of the extended auxiliary spring.

[Fifth Embodiment-Ultrasonic Inspection Apparatus 100d]
FIG. 15 is a schematic partial cross-sectional view of the ultrasonic inspection apparatus according to the fifth embodiment at the time of diameter expansion. FIG. 16 is a schematic partial cross-sectional view of an ultrasonic inspection apparatus according to the fifth embodiment. FIG. 17 is a schematic partial cross-sectional view of the ultrasonic inspection apparatus according to the fifth embodiment when the diameter is reduced.

An ultrasonic inspection apparatus 100d shown in FIGS. 15 to 17 is a modification of the ultrasonic inspection apparatus 100c according to the fourth embodiment. Specifically, in the internal moving part 110d, the expansion / contraction arm 400d and its constituent arm pieces (main arm 411d and link arm 412d), wheel 500d, shaft housing part 210d, fixing ring 224d (fixing part 324d), sliding ring 221d (Movable part 321d), sliding ring 216d, air cylinder 300d and its constituent members (air tank 330d, follow-up part 340d, auxiliary spring 350d), free space Sd are respectively included in ultrasonic inspection apparatus 100c according to the fourth embodiment. Expansion / contraction arm 400c and its constituent arm pieces (main arm 411c and link arm 412c), wheel 500c, shaft housing part 210c, fixed ring 224c (fixed part 324c), sliding ring 221c (movable part 321c) in internal moving part 110c , Sliding ring 21 c, air cylinder 300c and its components (air tank 330c, tracking unit 340 c, the auxiliary spring 350c), the same as the free space Sc. On the other hand, a sliding ring 228d and a fixing ring 229d are provided instead of the fixing ring 227c of the ultrasonic inspection apparatus 100c according to the fourth embodiment.

The other end of the auxiliary spring 350d is fixed, and the sliding ring 228d is provided so as to be slidable on the surface of the shaft housing portion 210 in the axial direction. The fixing ring 229d is fixed to the shaft housing part 210.

[Scale operation]
As shown in FIG. 15, at the time of diameter expansion, expansion / contraction of the expansion / contraction arm 400d occurs in the direction of the arrow SU in the aligned state as in the fourth embodiment.
On the other hand, the auxiliary spring 350d moves in the retraction direction with the movement of the sliding

rings

226d and 228d.

FIG. 16A and FIG. 16B illustrate a case where the diameter is further expanded from the state of FIG.
In the present embodiment, the fixing ring 229d has an abutting wall 229Hd that abuts the end wall 228Hd on the retracting direction side of the sliding ring 228d.
Here, when the expansion / contraction control unit 121 (see FIG. 1) is further operated from the state of FIG. 15 and air is further fed into the space AR in the follower 340d by sending air into the air tank 330d, the auxiliary spring 350d is also the same. As shown in FIG. 16A, the end wall 228Hd of the sliding ring 228d on the retreating direction side abuts against the contact wall 229Hd. Thereby, the other end of the auxiliary spring 350d is fixed.

In this case, depending on the degree of acceleration of the movable portion 321d, the movable portion 321d may further move in the direction of the arrow in the drawing as shown in FIG. 16 (b). In this case, the auxiliary spring 350d with the other end already fixed contracts to become a cushion.

On the contrary, as shown in FIG. 17, even when the diameter is reduced (when the diameter is reduced to the minimum), the expansion / contraction arm 400d is reduced in the direction of the arrow SD in the aligned state as in the fourth embodiment. Get up. In this case, the auxiliary spring 350d moves in the traveling direction F along with the movement of the sliding

rings

226c and 228d.

Further, as shown in FIG. 17, when the expansion / contraction arm 400c is reduced to the minimum, the auxiliary spring 350d is accommodated in the free space Sd as in the fourth embodiment.

[Sixth Embodiment-Ultrasonic Inspection Apparatus 100e]
FIG. 18 is a schematic partial cross-sectional view of the ultrasonic inspection apparatus according to the sixth embodiment at the time of diameter expansion. FIG. 19 is a schematic partial cross-sectional view of the ultrasonic inspection apparatus according to the sixth embodiment when the diameter is reduced.

18 and 19 is a modification of the ultrasonic inspection apparatus 100b according to the third embodiment. Specifically, in the internal movement unit 110e, the expansion / contraction arm 400e and its constituent arm pieces (main arm 411 piece e and link arm piece 412e), wheels 500e, and free space Se are ultrasonic waves according to the third embodiment. This is the same as the expansion / contraction arm 400b and its constituent arm pieces (main arm 411b and link arm 412b), wheels 500b, and free space Sb in the internal moving part 110b of the inspection apparatus 100b. On the other hand, instead of the shaft housing part 210b and the air cylinder 300 of the ultrasonic inspection apparatus 100b according to the third embodiment, a shaft housing part 210e and an air cylinder 300e are provided.

In the present embodiment, a fixing ring 224e and a sliding ring 221e are provided from the traveling direction F side as the connecting member 220e. The fixing ring 224e is fixed to the shaft housing portion 210e, and the sliding ring 221e is provided so that the shaft housing portion 210e can slide in the axial direction.

The base end portion of the main arm piece 411e is pivotally attached to the fixing ring 224e. The base end portion of the link arm piece 412e is pivotally attached to the sliding ring 221e.

[Air cylinder]
In the present embodiment, a part of the shaft housing portion 210e constitutes the air cylinder 300e. Specifically, the end portion of the shaft housing portion 210e forms a cylinder portion, and a piston portion 321e that slides in the axial direction so as to be able to contact the inner peripheral wall of the cylinder portion is a slit formed on the side surface of the shaft housing portion 210e. It continues to the sliding ring 221e through the hole. As a result, the sliding ring 221e can move together with the movement of the piston portion 321e.

An auxiliary spring 350e extending in the axial direction is provided between the fixing ring 224e and the sliding ring 221e. One end of the auxiliary spring 350e is fixed to the fixing ring 224e and the other end is fixed to the sliding ring 221e. . For this reason, the auxiliary spring 350e expands and contracts with the movement of the sliding ring 221e.

[Scale operation]
As shown in FIG. 18, when the diameter is expanded, the expansion / contraction control unit 121 (see FIG. 1) is operated to send air into the space AR in the air cylinder 300 e to extend in the direction of arrow E. Accordingly, the piston portion 321e moves together with the sliding ring 221e, so that the base end position of the link arm piece 412e moves in the same direction as the arrow E. At the same time, the auxiliary spring 350e is extended.
Therefore, as in the third embodiment, the expansion / contraction arm 400e expands in the direction of the arrow SU in the aligned state.

On the other hand, as shown in FIG. 19, even when the diameter is reduced (when the diameter is reduced to the minimum), the expansion / contraction arm 400e is reduced in the direction of the arrow SD in the aligned state as in the third embodiment. Get up. At the same time, the auxiliary spring 350e applies a force to the piston portion 321e to return the auxiliary spring 350c that has been extended by the diameter expansion, so that the diameter reducing operation smoothly occurs.

Further, when the expansion / contraction arm 400e is reduced to the minimum as shown in FIG. 19, the auxiliary spring 350e is accommodated in the free space Se as in the third embodiment.

In the present embodiment, the auxiliary spring 350e is disposed between the fixed ring 224e and the sliding ring 221e. However, the present invention is not limited to this mode. For example, the auxiliary spring 350e may be disposed on the side opposite to the fixed ring 224e with respect to the sliding ring 221e in the axial direction. In this case, one of the auxiliary springs is fixed to the sliding ring 221e, and the other is fixed to the outer peripheral portion of the cylindrical portion 200e. In this case, when the diameter is expanded, the auxiliary spring contracts, and when the diameter is contracted, the returning operation of the expansion / contraction arm 400e can be assisted by the return force of the contracted auxiliary spring.

[Seventh Embodiment-Ultrasonic Inspection Apparatus 100i]
FIG. 20 is a schematic partial side view of an ultrasonic inspection apparatus according to the seventh embodiment. FIG. 21 is a schematic front view of an ultrasonic inspection apparatus according to the seventh embodiment. Each part (internal movement part 110i, expansion / contraction arm 400i, wheel 500i) which comprises the ultrasonic inspection apparatus 100i shown in FIG. 20 is each part (internal movement part 110e, expansion / contraction arm 400e, etc.) of the ultrasonic inspection apparatus e concerning 6th Embodiment. It is the same as the wheel 500e).

In the ultrasonic inspection apparatus 100i shown in FIG. 20, wheels 850 are provided on the casing 800i. In FIG. 20, the ultrasonic inspection apparatus 100i is in a state in which the expansion / contraction arm 400i is contracted to a minimum. When the wheel 850 provided in the housing portion 800i is in contact with the inner wall surface L, the ultrasonic inspection apparatus 100i in the inner wall surface L is stably held.

Furthermore, when the ultrasonic inspection apparatus 100i is in the form of FIG. 20, as shown in FIG. 21, when the housing portion 800i is projected from the traveling direction F (see FIG. 20) side to the axial direction, All of 400i overlap. For this reason, the expansion / contraction arm 400i does not interfere with the radial size of the ultrasonic inspection apparatus 100i.

[Eighth Embodiment—Ultrasonic Inspection Apparatus 100e ′]
FIG. 22 is an external view of the ultrasonic inspection apparatus 100e ′ according to the eighth embodiment at the time of diameter expansion. FIG. 23 is an external view of a cable portion of the ultrasonic inspection apparatus 100e ′, and FIG. 24 is an external view of the ultrasonic inspection apparatus 100e ′ when the diameter is reduced. 25 is a cross-sectional view taken along line FF in FIG.

Each part (internal movement part 110e ', cylinder part 200e', shaft housing part 210e ', sliding ring 221e', fixing ring 224e ', air cylinder 300e', auxiliary spring constituting the ultrasonic inspection apparatus 100e 'shown in FIG. 350e '(omitted in the broken line illustration), expansion / contraction arm 400e', main arm piece 411e ', link arm piece 412e', wheel 500e ') are each part (internal movement part 110e) of the ultrasonic inspection apparatus e according to the sixth embodiment. , Cylinder portion 200e, shaft housing portion 210e, sliding ring 221e, fixing ring 224e, air cylinder 300e, auxiliary spring 350e, expansion / contraction arm 400e, main arm piece 411e, link arm piece 412e, and wheel 500e). The ultrasonic inspection apparatus 100e 'is the same as each part of the ultrasonic inspection apparatus 100e, except that each part is changed to a size suitable for further compaction and the like.

22 also shows the wiring of the cable 130 of the ultrasonic inspection apparatus 100e '. The cable 130 includes an air cable 133 communicating with the air cylinder 300 e ′, a motor cable 136 of the hollow shaft motor 610, and a probe cable 137 of the ultrasonic probe 710.

As shown in FIG. 22, the air cable 133 is wired outside from the end surface in the retraction direction of the shaft housing portion 210 e ′. The motor cable 136 exiting from the housing 800 is wired along the cylinder part 200e 'in the backward direction. The probe cable 137 passes through the shaft housing 210e 'and is inserted into the air cable 133 wired from the end surface in the backward direction.

Further, as shown in FIG. 23, the motor cable 136 and the air cable 133 into which the probe cable 137 is inserted are connected to the motor cable 136 and the probe in the air cable 134 that communicates with the air cable 133 via the repeater 135. Rewiring is performed with both of the tentacle cables 137 inserted. The air cable 134 is connected to the compressor.
As a material for the air cable 134, a flexible resin tube may be used. If necessary, a flexible shaft body such as a metal wire may be further provided along the inside or the outer periphery of the air cable 134. Accordingly, the ultrasonic inspection apparatus 100e ′ can be easily inserted into the tube by holding the air cable 134.

As shown in FIG. 24 and FIG. 25, the ultrasonic inspection apparatus 100e ′ when the diameter is most reduced is such that all of the expansion / contraction arm 400e ′ and the wheel 500e ′ overlap in the projection in the axial direction of the housing portion 800. It will be compact. In this case, the motor cable 136 wired outside from the housing portion 800 is located between the folded expansion / contraction arm 400e ′ at the outer peripheral portion of the cylindrical portion 200e ′, so that the ultrasonic inspection apparatus 100e ′ can be made compact. There is no problem. Note that the ultrasonic inspection apparatus 100e ′ slightly expands the diameter of the wheel 500e ′ so that a part of the wheel 500e ′ protrudes from the projection when the diameter is reduced to the maximum, so that the expansion / contraction arm in the tube is expanded. The diameter expanding operation may be made easier.

In FIG. 26, an aspect of changing the direction of the inside of the cheese mold tube will be described using an ultrasonic inspection apparatus 100e 'as an example. In FIG. 26, a pipe T into which the ultrasonic inspection apparatus 100e 'is inserted is a cheese-type pipe used for a fire hydrant, for example. The insertion port of the tube T is, for example, a small diameter tube having an inner diameter of 75 mm. The ultrasonic inspection apparatus 100 e ′ is inserted from the insertion port in the most contracted state, and when it reaches the branch portion of the tube T, the direction is changed while maintaining the contracted state. The ultrasonic inspection apparatus of the present invention exemplified by the ultrasonic inspection apparatus 100e ′ is designed to be compact in both the radial direction and the axial direction with respect to the axial center, thereby enabling 90-degree direction conversion in the tube. .

[Other examples]
In another example, a modification example not shown will be described.

[Modification of shaft housing]
In the above-described embodiment, the mode in which the shaft portion is the

cylindrical portion

200, 200a, 200b having the shaft housing portion 210 has been described, but the embodiment is not limited thereto. For example, the shaft portion may be a solid bar shape. Moreover, in the above-mentioned embodiment and other examples, the example in which the cross section of the shaft housing part 210 is circular was given, but the shape of the cross section is not limited to this. For example, arbitrary shapes, such as polygons, such as a rectangle and a hexagon, and those deformation | transformation shapes are accept | permitted.

Furthermore, in the above-described embodiment, the connecting

members

220, 220a, 220b, 220d, 220e, and 220e ′ are those in which the shaft-attached portion is provided on the ring portion having a circular cross section. However, the present invention is limited to this embodiment. Is not to be done. For example, an arbitrary shape such as a polygon such as a quadrangle and a hexagon and a deformed shape thereof is allowed for the outer periphery of the cross section of the ring portion. Further, only the shaft attachment portion may be fixed to the shaft housing portion 210 instead of the connecting member that does not slide.

[Modification example of expansion and contraction part]
In the above-described embodiment, the example in which the expansion / contraction part is the

air cylinders

300, 300 c, 300 d, 300 e, and 300 e ′ that can be controlled by the expansion / contraction control part 121 has been described. If it has, it will not specifically limit. For example, a hydraulic spring, an air spring, and a coil spring that drives the movable part by electrical control may be used. In this case, the coil spring may have an axial center disposed on the outer peripheral portion of the

cylindrical portions

200, 200 a,..., 200 e, 200 i, 200 e ′, or may be coaxial with the axial center of the shaft housing portion 210. It may be arranged. In either case, the diameter can be reduced and expanded in the pipe.

In the above-described embodiment, the air cylinder 300 extends in the axial direction. However, the present invention is not limited to this. For example, the air cylinder 300 is provided so as to extend in the radial direction. In this case, both ends of the air cylinder are fixedly connected to a connecting member that does not slide and to any of the arm pieces constituting the expansion /

contraction arms

400, 400a, 400b.

[Modification of expansion / contraction arm]
In the above-described embodiment, the embodiment in which the number of the expansion /

contraction arms

400, 400a,..., 400e, 400i, 400e ′ is 3 or 6 has been described, but the embodiment is not limited thereto. The number of expansion / contraction arms may be plural.

In the above-described embodiment, the expansion /

contraction arms

400, 400a,..., 400e, 400i, and 400e 'have been described as having specific link mechanisms, but the present invention is not limited to this. Any other mechanism is acceptable as long as it is a link mechanism that links the expansion and contraction operations of the

air cylinders

300, 300c, 300d, 300e, and 300e 'with the expansion and contraction operations of the expansion and

contraction arms

400, 400a, ..., 400e, 400i, and 400e'. The

[Modified example of combination of expansion / contraction part and expansion / contraction arm]
For example, instead of the ultrasonic inspection apparatus 100 according to the first embodiment, the ultrasonic inspection apparatus 100a according to the second embodiment, and the air cylinder 300 of the ultrasonic inspection apparatus 100b according to the third embodiment, the fourth embodiment is used. The air cylinder 300c of the ultrasonic inspection apparatus 100c, the air cylinder 300d of the ultrasonic inspection apparatus 100d according to the fifth embodiment, and the air of the

ultrasonic inspection apparatuses

100e, 100i, and 100e 'according to the sixth to eighth embodiments. Any of the

cylinders

300e and 300e ′ can be arbitrarily combined.

[Modified examples of running section]
In the above-described embodiment, an example in which the traveling unit is the

wheels

500, 500a,..., 500e, 500i, and 500e ′ has been described, but the embodiment is not limited thereto. For example, a caterpillar may be used. In that case, for example, a pair of gears are coaxially attached to both ends of the synchronization arm piece 414 in the axial direction so as to sandwich the synchronization arm piece 414, and a caterpillar is wound around each gear.
The wheels may be self-propelled having a drive mechanism. Furthermore, the traveling unit may be capable of traveling by a water injection mechanism.

[Modification of detection unit]
In the above-described embodiment, an example in which a part of the ultrasonic probe 710 (specifically, the ultrasonic wave propagation part 712) is inserted into the hollow part of the hollow rotating member 611 has been described. The amount of insertion is not limited to this mode. All of the ultrasonic probe 710 may be inserted into the hollow portion of the hollow rotating member 611, or conversely, all of the ultrasonic probe 710 may be disposed outside the hollow portion of the hollow rotating member 611. Good. In the latter case, the ultrasonic probe 710 may be fixed in the shaft housing part 210.

[Variation of rotation sensor]
In the above-described embodiment, the position marker 771 is fixed to the hollow rotating member 611. However, the position marker 771 is fixed to the rotating holder 724 of the acoustic reflector 720 as long as the position marker 771 can be detected by the sensor 772. May be. In the above-described embodiment, the rotation sensor is the one-rotation sensor 770. However, the present invention is not limited to this. For example, a rotary encoder may be used.

[Modification of the casing]
In the above-described embodiment, the case in which the casing units 800 and 800i include the detection unit 700 has been described. However, other components may be further included. Examples of other components include an imaging device and illumination (LED as an example). These components can be provided at the ends of the casings 800 and 800i on the traveling direction side. Thereby, an ultrasonic inspection can be performed while photographing while illuminating the inside of the tube.

In addition to the above, other components that can be connected may be mentioned as the other components provided at the end of the casing 800, 800i on the traveling direction side. The connectable part is a part that can be detachably connected to the connecting member, for example, by engagement or fitting. An example of usage of such a connectable part will be described as follows.

A pulling member such as a cable with a connecting member (for example, a hook) is inserted into the pipe from the opening end located on the traveling direction side, which is different from the entrance where the ultrasonic inspection apparatus is inserted, of the pipe to be measured, After the connecting member is connected to the connectable portion provided in the housing parts 800 and 800i, the ultrasonic inspection apparatus can be advanced in the traveling direction by pulling the pulling member out of the opening end. it can.

[Modification of internal moving part]
In the above-described embodiment, an example in which one internal moving

unit

110, 110a,..., 110e, 110i, and 110e ′ is provided per one

ultrasonic inspection apparatus

100, 100a,. It is not limited to this aspect. One

ultrasonic inspection apparatus

100, 100a, ..., 100e, 100i, 100e 'may include a plurality of mutually connected internal moving

units

110, 110a, ..., 110e, 110i, 110e'.

[Layer thickness measurement method]
Hereinafter, a method for testing the thickness of the metal layer in the lining metal tube will be described as an example of the ultrasonic measurement method performed by the ultrasonic inspection apparatus.
FIG. 27 is a partially cutaway view schematically showing an example of a layer thickness test method according to the present embodiment. FIG. 28 is a schematic view seen from the axial direction of the lining pipe to be tested in the layer measurement test method of FIG. FIG. 29 is a schematic partially enlarged view showing an example of a layer thickness test method in the present embodiment. FIG. 31 is a block diagram showing a part of the layer thickness test apparatus.

27 and 28, the test target of the layer thickness test apparatus 100j (one aspect of the ultrasonic inspection apparatus) in the layer thickness test method is a lining pipe 900 (one aspect of the pipe). The lining pipe 900 is such that a cement-containing layer 920 is lined on the inner surface of a metal pipe 910 and embedded in the ground. For example, plumbing of waterworks, sewage, industrial water and agricultural water is included.

Examples of the material of the metal tube 910 include iron (particularly cast iron) and steel.
Cast iron is an iron-carbon alloy containing about 2.0% or more of carbon. Generally, the carbon content is 2.0% or more and 4.5% or less and silicon is 0.5% or more and 3.0% or less, manganese is 1.0% or less, phosphorus and / or sulfur is 0.1%. In many cases, it also contains about% (% is based on weight).

Types of cast iron include white cast iron, mottled cast iron and gray cast iron as normal cast iron, and reinforced cast iron as tough cast iron, spheroidal graphite cast iron (for example, nodular cast iron, ductile cast iron), malleable cast iron and alloys Cast iron is mentioned. In the case of water pipes, specifically, Japanese Industrial Standards (JIS G 5521, 5522, 5523, 5524, 5526, 5527), Japan Waterworks Association Standards (JWSA G 102, 103, 105, 106, 108, 109, 110, 111, 113, 114, 114-2), Japan Sewerage Association Standard (JSWASJG-1, G-2), Japan Ductile Iron Pipe Association Standard (JDPA G 1001, 1002, 1003, 1004, 1007, 1008, 1009, 1010, 1011, 1012, 1013, 1014, 1015, 1016, 1017, 1018, 1019, 1020, 1021, 1022, 1024, 1025, 1026, 1027, 1028, 1029, 1030, 1031, 1032, 1033, 1034, 1035, 1036, 1037, 1038, 1039, 1040, 1041, 1042, 1043, 1044, 1045, 1046, 1047, and 1048).

Steel is an iron-carbon alloy containing about 2.0% or less of carbon (% is based on weight). Examples include carbon steel and stainless steel.

Further, the nominal diameter of the metal tube 910 is, for example, 100 or more, more specifically, 100 or more and 300 or less.

The material of the cement-containing layer 920 may be a lining material containing cement. Examples of the cement include pollite cement, mixed cement (for example, blast furnace cement, fly ash cement, silica cement), eco cement, hydrated cement, and unhydrated cement. Typical pollite cements fire a mixture of limestone and clay, silica, and iron oxide, and clinker such as tricalcium silicate, dicalcium silicate, tricalcium aluminate, iron tetracalcium aluminate After that, a small amount of gypsum was added to the clinker and pulverized. In addition to the components described above, air and / or water may be present in the cement.

The cement-containing layer 920 is formed by layering the above-described material containing cement. In materials containing cement, examples of materials mixed with cement include fine aggregates such as sand, coarse aggregates such as gravel and crushed stone, and admixtures. More specifically, materials containing cement include mortar and concrete (eg, fresh concrete, hardened concrete).

In addition, mortar is generally obtained by adding a fine aggregate alone to cement or adding both a fine aggregate and an admixture to cement. In the case of water pipes, specifically, it is stipulated in Japan Industrial Standard (JIS A5314), Japan Waterworks Association Standard (JWWA A 107, JWWA A 113), Japan Ductile Iron Pipe Association Standard (JDPA Z 2013, JDPA Z 2015), etc. ing. When the blending ratio of the cement and fine aggregate is 1: 1.5 or more and 1: 3.5 or less as a composition in a healthy state (that is, an undegraded state), and an admixture is blended , Is defined as 15% or less relative to the cement mass (% is based on weight).

Further, the cement-containing layer 920 may have another coating layer, that is, a seal coat, on the inner surface of the cement-containing material layer. The material of the further another coating layer includes, for example, a resin, more specifically, an acrylic resin and a vinyl chloride resin.

27 and 28, the lining pipe 900 is filled with water W. The layer thickness test apparatus 100j is disposed inside the lining pipe 900. The layer thickness test apparatus 100j includes a probe part 700j (one aspect of the detection part), a holding part 200j (one aspect of the shaft part), and a separation part 400j (implemented with an expansion / contraction arm). Furthermore, as shown in FIG. 31, the layer thickness test apparatus 100 j includes a waveform acquisition unit 150, a determination unit 160, a thickness calculation unit 170, and a display unit 180.

As shown in FIG. 28, the probe unit 700j includes an ultrasonic probe 710, a sensor holder 732 that holds the ultrasonic probe 710 toward the cement-containing layer 920 at one end, and the other end of the sensor holder 732 And an arm member 733 that couples the part to the holding part 200j. The ultrasonic probe 710, the sensor holder 732, and the arm member 733 are arranged so as to be coaxial with each other in the radial direction of the lining pipe 900.

The ultrasonic probe 710 shown in FIG. 28 generates an ultrasonic wave and transmits and receives an ultrasonic beam. The ultrasonic probe 710 mainly includes an acoustic lens, an acoustic matching layer (matching layer), a vibrator (element), and a backing (damper) in a housing.

The acoustic lens is provided to focus the ultrasonic beam using refraction and improve the resolution. A concave lens is generally used as the acoustic lens. The sound speed of the acoustic lens is about 2000 m / sec or more and 3000 m / sec or less, and an acrylic resin or polystyrene resin is used as the material.
The acoustic matching layer (matching layer) is also called a λ / 4 layer. In order to reduce the acoustic impedance difference between the transducer and the specimen and to efficiently transmit and receive ultrasonic waves, the multilayer arrangement is used.
The vibrator (element) transmits and receives ultrasonic waves. It is a so-called transducer that vibrates when a voltage is applied to generate ultrasonic waves, and generates a voltage when vibrated. It is also called a piezoelectric element, and is composed of a material having a piezo effect (piezoelectric effect). A typical example of such a material is quartz, and more generally, PZT (lead zirconate titanate). Other examples include PVDF (polyvinylidene fluoride).
The backing (damper) is disposed on the back surface of the vibrator, and suppresses the propagation of ultrasonic waves to the rear. This contributes to shortening the pulse width.

Ultrasonic probes include a focus type probe and a straight type probe. The focus-type probe is designed so that the transmitted ultrasonic wave is temporarily focused at a point at a certain distance (see symbol D in FIG. 27) from the head unit. In the focus type probe, ultrasonic waves transmitted from each point of the head unit are transmitted in such a way that they are not parallel but gather toward the point. The rectilinear probe is designed so that ultrasonic waves transmitted from each point of the head part are parallel. In order to obtain a sharp peak, a focus type probe is preferable.

In the present embodiment, a single probe method, that is, a method using one transmission / reception integrated ultrasonic probe 710 is illustrated, but the present invention is not limited to this.
For example, a two-probe method, that is, a method using a transmitting probe and a receiving probe may be used. The transmitting probe and the receiving probe may be functionally and physically separated from each other. In this case, the transmitting probe and the receiving probe are oblique to the tangent to the inner surface of the lining layer (that is, more than 0 degrees 90 degrees). The ultrasonic wave is transmitted from the transmitting probe so that the incident angle is less than 50 degrees, and the reflected wave reflected obliquely (that is, with a reflection angle of more than 0 degrees and less than 90 degrees) is received by the receiving probe. Can do.
In addition, a method of using a plurality of transmission / reception integrated sensors may be used. Further, a method using a plurality of two-probe methods may be used.

27 and 28, the holding part 200j is provided so as to be interposed between the two parts in order to hold the probe part 700j and the separating part 400j. Further, in the case of FIGS. 27 and 28, the probe portion 700j and the separation portion 400j are maintained so that the angle (vertical) of the probe portion 700j with respect to the tangent TL (see FIG. 28) of the inner peripheral surface of the cement-containing layer 920 is kept constant. Can also be connected. As shown in FIG. 28, the holding portion 200j includes a rotating shaft 250j, a cylindrical casing 210j (one aspect of the shaft housing portion) arranged so as to be coaxial with the axis of the lining pipe 900, and a connecting ring 220j. (One aspect of the connecting member).

As shown in FIGS. 27 and 28, the rotary shaft 250j has one end fixed to the arm member 733 of the probe portion 700j and the other end supported at the axial center position of the cylindrical casing 210j. It is rotationally driven by a motor (not shown) accommodated therein. The motor may be a solid shaft motor instead of the hollow shaft motor 610 described in the first to eighth embodiments. The solid shaft motor can be directly fixed to the rotating shaft 250j. Thus, along with the rotation of the rotation shaft 250j, the ultrasonic probe 710 maintains an angle (perpendicular) with respect to the surface of the cement-containing layer 920 via the arm member 733 on the inner peripheral surface of the cement-containing layer 920. Rotate along (arrows in FIGS. 27 and 28).

As shown in FIGS. 27 and 28, the separating portion 400j separates the head portion (a portion where ultrasonic waves are transmitted) of the ultrasonic probe 710 of the probe portion 700j and the surface of the cement-containing layer 920. Is provided. The distance D (see FIG. 27) between the head portion of the ultrasonic probe 710 of the probe unit 700j and the cement-containing layer 920 is the wavelength of the transmitted ultrasonic wave and the characteristics (straight line) of the ultrasonic probe 710. There is no particular limitation as it may differ depending on the type and the focus type. For example, from the viewpoint of easily maintaining good detection sensitivity, the distance D can be set to 5 mm or more.

As shown in FIG. 28, the spacing portion 400j includes three parallel link mechanisms 410j that can radially expand outward in the radial direction of the inner circumference of the cement-containing layer 920 and degenerate radially inward. Further, on the radially outer side of each parallel link mechanism 410j, there is provided a wheel 500j that forms a pair in the axial direction of the lining pipe 900 (see FIG. 27) and can travel in the axial direction.

As shown in FIG. 27, the parallel link mechanism 410j includes a cross arm 415j and a link plate 414j (one aspect of a synchronization arm).
Two connecting rings 220j are provided in the axial direction of the cylindrical casing 210j, one is fitted on the outer peripheral surface of the cylindrical casing 210j, and the other is slidable in the axial direction on the outer peripheral surface of the cylindrical casing 210j. It is loosely fitted. As shown in FIG. 28, each of the connecting rings 220j has three connecting protrusions for connecting the cross arm 415j projecting radially on the surface.

The cross arm 415j can change the crossing angle of a pair of arms, and as shown in FIG. 27, one end of each arm is connected to each of the two connecting rings 220j. The link plate 414j connects the other end of the cross arm 415j and connects a pair of wheels 500j. In the link plate 414j, one connecting position at the other end of the cross arm 415j is fixed, and the other connecting position is slidable in the axial direction of the lining pipe 900.

As shown in FIG. 27 and FIG. 28, the spacing portion 400j is crossed so that the three pairs of wheels 500j abut against the cement-containing layer 920 and the axis of the cylindrical casing 210j coincides with the axis of the lining pipe 900. By adjusting the crossing angle of the arms 415j, the ultrasonic probe 710 of the probe unit 700j and the cement-containing layer 920 are kept apart.

In the layer thickness test method of the present invention, the ultrasonic inspection described in the first embodiment and the eighth embodiment described above using a hollow shaft motor instead of the layer thickness test apparatus 100j described in FIGS.

Devices

100, 100a,..., 100e, 100i, 100e ′ may be used.

FIG. 29 is an enlarged schematic view of the ultrasonic probe 710 and a part of the lining tube 900 when the layer thickness test is performed. As shown in FIG. 29, an ultrasonic wave (transmitted wave R) is transmitted from the head portion of the ultrasonic probe 710. The transmitted wave R is transmitted so as to be perpendicular to the tangent TL of the inner peripheral surface Ls of the cement-containing layer 920.

The wavelength of the transmitted ultrasonic wave is particularly limited because it can vary depending on the characteristics (linear type and focal type) of the ultrasonic probe 710, the distance between the head portion of the ultrasonic probe 710 and the surface of the cement-containing layer 920, and the like. Is not to be done. For example, the lower limit of the wavelength of the ultrasonic wave is 1 MHz or more, and 1.5 MHz, 1.8 MHz, and further 2 MHz are preferable. The upper limit of the wavelength of the ultrasonic wave is, for example, 10 MHz, more preferably 9 MHz, further 7.5 MHz, further 5 MHz, and further 3.5 MHz. When the above range is exceeded, the sensitivity tends to be low with respect to the signal noise ratio (S / N ratio). Below the above range, the dead zone (that is, the skirt width of each peak) becomes wide, the layer thickness measurement accuracy tends to decrease, and the layer thickness measurable range tends to narrow.

In an example of the model case brought about by the layer thickness test, as shown in FIG. 29, the transmitted wave R reaches the outer surface Lb of the metal tube 910, and the inner peripheral surface Ls of the cement-containing layer 920, the cement-containing layer. A reflected surface RS reflected by the boundary surface Li between the metal tube 910 and the outer surface Lb of the metal tube 910 and reflected by the inner peripheral surface Ls, a first reflected wave RI1 reflected first by the boundary surface Li, and The first reflected wave RB1 first reflected by the outer surface Lb is received by the ultrasonic probe 710.

Furthermore, FIG. 30 schematically shows a reflection path of ultrasonic waves when multiple echo peaks are acquired by multiple reflection in the metal layer 910.
When generalizing that the transmitted wave R is n-fold reflected in the metal layer 910 (n is an integer of 2 or more, the same applies hereinafter), the reflected wave reflected by the outer surface Lb at the (n−1) th time. Is the (n-1) th reflected wave RB (n-1), and the (n-1) th reflected wave RB (n-1) is reflected again at the outer surface Lb for the nth time by reflecting off the boundary surface Li. The reflected wave that has been reflected is the nth reflected wave RBn.
Therefore, the reflected wave that the transmitted wave R is first reflected by the outer surface Lb of the metal layer 910 is described as the first reflected wave RB1, and the reflected wave RB1 is reflected by the boundary surface Li, so that the reflected wave RB1 is reflected the second time on the outer surface Lb. The reflected wave reflected again is referred to as a second reflected wave RB2. In addition, when the number of the reflected light is not particularly limited, it is simply described as a reflected wave RB.

The received signal is processed into a waveform of reflected wave intensity with respect to propagation time in the waveform acquisition unit 150 (see FIG. 31). More specifically, the received wave (in the case of FIG. 29, reflected wave RS, RI1, RB1) is amplified by a signal amplifier, noise is removed by a band pass filter or the like, digitized by an A / D converter, and thereafter The waveform is acquired by performing an averaging process of adding and averaging the digitized waveforms on the same time axis. The acquired waveform is stored together with the measurement position information. The acquired waveform can be displayed on the display unit 180.

The peak pattern (intensity of reflected wave with respect to propagation time) in this model case is schematically shown in FIG. FIG. 32 shows the propagation time on the horizontal axis and the signal intensity on the vertical axis. As shown in FIG. 32, three echo peaks are detected with separable resolution. More specifically, the reflected wave RS reflected by the inner peripheral surface Ls of the cement-containing layer 920 is detected as the reflected wave having the shortest propagation time. The first reflected wave RI1 reflected first at the boundary surface Li is detected as the reflected wave having the second longest propagation time. The first reflected wave RB1 that is first reflected by the outer surface Lb is detected as the reflected wave having the third longest propagation time.

Furthermore, in some cases, multiple echo peaks including two or more reflected waves RB may be obtained by multiple reflection in the metal layer 910. That is, the (n−k + 1) th reflected wave RB (n−k + 1), the (n−k + 2) th reflected wave RB (n−k + 2), the (n−k) th reflected wave RB (n−k), (n−k + 3) reflected wave RB (n−k + 3), (n−k + 4) th reflected wave RB (n−k + 4)... may be acquired (k is an integer equal to or greater than 1. In the following, the same applies. .) In this case, the multiplex composed mainly of the first reflected wave RB1 and the second reflected wave detected by detecting the second reflected wave RB2 (see FIG. 29) secondly reflected by re-reflection on the outer surface Lb. There is a tendency that echo peaks are often acquired.

32, the echo peak of each reflected wave RS, RI1, RB1 is displayed as a single peak of normal distribution, but it is not limited to such a shape. The echo peak may be at least an aspect in which the echo peaks of the first reflected waves RI1 and RB1 necessary for measuring the thickness of the metal tube 910 are detected so as to be distinguishable from each other. For example, the aspect which formed the peak group by the synthesized wave by interference of the reflected wave which reflected the same interface for the echo peak may be sufficient. Each echo peak of the reflected waves RS, RI1, RB1 has, for example, an S / N ratio of 2.5 or more, preferably 3 or more.

In the determination unit 160 (see FIG. 31), at least the first reflected waves RI1 and RB1 or at least two reflected waves RB among the reflected waves RB in the case of n-layer reflection in the metal layer 910 are determined as peaks. It is determined whether or not detection has been made with possible resolution, or resolution and S / N ratio (for example, S / N ratio is 2.5 or more, preferably 3 or more).

For example, when a peak pattern (echo peak of reflected waves RS, RI1, RB1) as shown in FIG. 32 is detected so as to be discriminable, the thickness of the metal tube 910 of the lining tube 900 can determine the thickness. It can be judged that.

Similarly, when the echo peaks of two or more reflected waves RB are detected in a distinguishable manner, it can be determined that the thickness of the metal layer 910 of the lining tube 900 is such that the thickness can be obtained.

In the case of the peak pattern as shown in FIG. 32, the thickness calculation unit 170 (see FIG. 31) further reduces the propagation time difference (μ seconds) between the first reflected wave RB1 and the first reflected wave RI1 to 1/2. The thickness of the metal tube 910 is calculated by multiplying by the speed of sound.

Similarly, when two or more reflected wave RB peaks are detected in a distinguishable manner, a pair of (two) reflected wave RB peaks arbitrarily selected from the detected reflected wave RB peaks are used. Based on the difference in propagation time, the thickness of the metal layer can be calculated.

For example, when using the (nk) reflected wave RB (nk) and the (nk + 1) reflected wave RB (nk + 1), the (nk) reflected wave RB (nk) is used. The thickness of the metal tube 910 is calculated by multiplying the difference in propagation time (μ seconds) between the (n−k + 1) th reflected wave RB (n−k + 1) and the sound speed by 1/2.

Further, for example, when using the (nk) reflected wave RB (nk) and the (nk + 3) reflected wave RB (nk + 3), the (nk) reflected wave RB (nk) ) And the (n−k + 3) reflected wave RB (n−k + 3) by multiplying the difference in propagation time (μ seconds) by 1/3, and further multiplying by 1/2 and the sound velocity, the thickness of the metal tube 910 is increased. Calculate the thickness.

In addition, when there are a plurality of patterns for selecting a pair of reflected waves RB from the peaks of two or more reflected waves RB detected in a distinguishable manner, a value obtained by calculating the plurality of patterns and averaging the calculation results May finally be the thickness of the metal tube 910.

Alternatively, for two or more reflected waves RB arbitrarily selected from the peaks of the two or more reflected waves RB detected in a distinguishable manner, first, the relationship of the propagation time to the path distance of the reflected wave RB is determined by the least square method or the like. By approximating to the linear function, the coefficient of the approximated linear function is calculated as an average value of the time during which the reflected wave RB travels once between the boundary surface Li and the outer surface Lb of the metal layer 910, and then calculated. The thickness of the metal layer 910 may be obtained by multiplying the average value by 1/2 and the speed of sound.

The determination result by the determination unit 160 and / or the result of the wall thickness calculation unit 170 can be displayed on the display unit 180.

FIG. 33 shows a peak pattern in another example of a model case caused by the layer thickness test.
In FIG. 33, the echo peak of the reflected wave RS is detected so as to be separable while the echo peak of the first reflected wave RI1 and the first reflected wave RB1 cannot be separated.

33, when the peak pattern as shown in FIG. 33 is detected, it can be determined that the metal tube 910 of the lining tube 900 has been thinned to such an extent that it cannot be measured. On the other hand, the cement-containing layer 920 is not deteriorated, or even if it is deteriorated, it is determined that the degree is small enough to allow the transmission wave R to enter the cement-containing layer 920. can do.

In the example of FIGS. 32 and 33, the aspect in which the thickness of the metal tube 910 is measured based on the detection peaks of the first reflected wave RI1 and the first reflected wave RB1 is shown. However, the second reflection is performed together with the first reflected wave RB1. When the wave RB2 (see FIG. 29) is detected with a detectability that can be distinguished from each other (for example, the S / N ratio is 2.5 or more, preferably 3 or more), the first reflected wave RB1 and the second reflected wave RB2 Similarly, the thickness of the metal tube 910 can be measured based on the detected peak.

FIG. 34 shows a peak pattern in yet another example of the model case caused by the layer thickness test.
In FIG. 34, only the echo peak of the reflected wave RS is detected. When a peak pattern as shown in FIG. 34 is detected, it can be determined that the deterioration of at least the cement-containing layer 920 of the lining pipe 900 is advanced. The state in which the deterioration of the cement-containing layer 920 is advanced is a state in which the transmitted wave R does not enter the cement-containing layer 920 due to at least one of an increase in porosity, a decrease in the weight ratio of cement, and a decrease in calcium concentration. Say. Examples of the deterioration degree of the cement-containing layer 920 when such a peak pattern is generated include a case where the weight ratio of the cement is 20% by weight or less and / or a case where the calcium concentration is 100,000 ppm or less. . In addition, the case where the porosity of the cement-containing layer 920 is 0.5% or more is also included.

Moreover, in the above-mentioned example, the aspect in which the ultrasonic probe 710 of the probe unit 700j fixed to the rotation shaft 250j rotates along the inner peripheral surface of the cement-containing layer 920 (arrows in FIGS. 27 and 28) is shown. However, it is not limited to this aspect. For example, the probe unit 700j including the ultrasonic probe 710 that is not fixed to the rotation shaft 250j may be self-propelled while maintaining a distance and an angle (perpendicular) to the surface of the cement-containing layer 920.

Further, like the layer thickness test apparatus 100k which is another example of the layer thickness test apparatus 100j shown in FIG. 35, the ultrasonic probe 710 of the probe unit 700k fixed to the non-rotating axis is formed of the lining tube 900. An ultrasonic wave may be provided so as to be transmitted in the axial direction from the axial position. In this case, the mirror 720k (one aspect of the acoustic reflection unit) is provided so as to be rotatable about the axis (indicated by an arrow in FIG. 35), and the ultrasonic wave R transmitted from the ultrasonic probe 710 is applied to the cement. The light is refracted by the inclined surface 723k on the surface of the mirror 720k so as to be incident on the inner surface of the containing layer 920 at a predetermined angle (perpendicular).

In the above-described example, the layer thickness test is performed on the lining pipe 900 lined with the cement-containing layer 920 having a curved surface. However, the present invention is not limited to this mode. For example, a layer thickness test may be performed on a metal multilayer body in which a cement-containing layer having a flat surface is laminated so that the surface opposite to the surface is in contact with the metal surface.

Furthermore, in the above-described example, the aspect in which the porous layer provided on the surface of the metal tube 910 is the cement-containing layer 920 is shown, but the porous layer is not limited to the cement-containing substance.

Furthermore, in the above-described example, the layer thickness test apparatus 100j exemplifies a mode in which the probe unit 700j is connected to the separation unit 400j via the holding unit 200j. However, the present invention is not limited to this mode. For example, the layer thickness test apparatus 100j may have a configuration in which the probe unit is directly connected to the separation unit. In this case, the spacing portion may have a function of keeping the angle of the probe portion perpendicular to the surface of the cement-containing layer or the tangent to the surface.

As described above, according to the layer thickness test using the layer thickness test apparatuses 100j and 100k, when at least the peaks of the first reflected waves RI1 and RB1 (for example, the peak pattern in FIG. 32) are observed in the waveform acquisition process, It can be determined that the metal tube 910 has a thickness that allows thickness measurement. In this case, the thickness of the metal tube 910 can be accurately obtained by multiplying the detection time difference between the peak of the first reflected wave RB1 and the peak of the first reflected wave RI1 by the speed of sound.

In addition, when the peak pattern of FIG. 33 is observed, it can be determined that the thickness reduction of the metal tube 910 is large. When the peak pattern of FIG. 34 is observed, it can be determined that at least the degree of deterioration of the cement-containing layer 920 is large.

[Effects achieved by the embodiment and other examples]
The

ultrasonic inspection apparatuses

100, 100a,..., 100e, 100i, 100e ′ are expanded so that the expansion /

contraction arms

400, 400a,..., 400e, 400i, 400e ′ are stretched toward the inner wall L when inserted into the tube. Then, the

wheels

500, 500a,..., 500e, 500i, 500e ′ come into contact with the inner wall surface L. Thereby, the

ultrasonic inspection apparatuses

100, 100a,..., 100e, 100i, 100e ′ are held. Expansion / contraction of the expansion /

contraction arms

400, 400a,..., 400e, 400i, 400e ′ can be performed by expansion / contraction of the

air cylinders

300, 300c, 300d, 300e, 300e ′. For this reason, the diameter reduction and diameter expansion in a pipe become free.

Also, since the acoustic reflector 720 is rotatably provided, the ultrasonic probe 710 can be provided in a fixed state. As a result, the size of the

ultrasonic inspection apparatus

100, 100a,..., 100e, 100i, 100e ′ in the radial direction centered on the axis of the

cylindrical portion

200, 200a,. The size of the expansion /

contraction arms

400, 400a,..., 400e, 400i, 400e ′ can be reduced.

Further, since the ultrasonic wave is transmitted through the hollow portion of the hollow rotating member 611 by using the hollow shaft motor 610 for the rotation of the acoustic reflecting portion 720, the ultrasonic probe 710 itself is connected to the

cylindrical portion

200, 200a,..., 200e, 200i, 200e ′ can be arranged coaxially. This also makes it possible to reduce the size of the

ultrasonic inspection apparatuses

100, 100a,..., 100e, 100i, 100e 'in the radial direction.

The rod 311 of the

air cylinders

300, 300c, 300d, 300e, and 300e ′, the

movable portions

321c and 321d of the

air cylinders

300c and 300d, and the piston 321e of the

air cylinders

300e and 300e ′ are

cylindrical portions

200, 200a,. , 200e ′ is arranged so as to move in the axial direction, and the size of the radiation direction of the

ultrasonic inspection apparatus

100, 100a,..., 100e, 100i, 100e ′ when the expansion / contraction arm is most contracted is compact. Can be.

Since the air cylinder 300 is fixed to the connecting

members

220, 220a, 220b so as to expand and contract in the axial direction of the

cylindrical portions

200, 200a, 200b, the radial direction, that is, the expansion / contraction direction SU of the expansion /

contraction arms

400, 400a, 400b. , Does not expand or contract to SD. Therefore, even when the air cylinder 300 is disposed on the outer peripheral portion of the

cylindrical portions

200, 200a, 200b, the size of the

ultrasonic inspection apparatus

100, 100a, 100b in the radial direction when the expansion / contraction arm is most contracted is made compact. be able to.

Since the

air cylinders

300c and 300d include the entire

shaft housing portions

210c and 210d, and the

air cylinders

300e and 300e ′ include a part of the shaft housing portion 210e, the

ultrasonic inspection apparatuses

100c, 100d, 100e, 100i, and 100e ′. The size of the radiation direction can be made compact.

In the

ultrasonic inspection apparatuses

100, 100a,..., 100e, 100i, 100e ′, the expansion /

contraction arms

400, 400a,..., 400e, 400e ′ have free spaces S, Sa,. ,..., 400e, 400e ′, when the

air cylinders

300, 300c, 300d, 300e, 300e ′ are at their smallest size, at least some of the

air cylinders

300, 300c, 300d, 300e ′ are accommodated in the free spaces S, Sa,. Therefore, the size of the

ultrasonic inspection apparatus

100, 100a,..., 100e, 100i, 100e ′ in the radial direction when the expansion /

contraction arms

400, 400a,. .

The

ultrasonic inspection apparatuses

100, 100a,..., 100i, 100e ′ project the housing parts 800, 800i in the axial direction when the expansion /

contraction arms

400, 400a,..., 400e, 400i, 400e ′ are most contracted. Further, since the expansion /

contraction arms

400, 400a,..., 400e, 400i, 400e ′ overlap, the size in the radial direction can be made compact.

The expansion / contraction arms 400a,..., 400e, 400i, 400e ′ extend substantially along the axis O of the cylindrical portions 200a,..., 200e, 200e ′ when they are most contracted, and the fixing

rings

224a, 224c to 224e, 224e. Because it has a simple structure that rotates at a rotation angle that does not exceed 90 degrees, centering on the shaft attachment part of ', it can be made compact in the radial direction and compact in the axis O direction. can do. Therefore, the space occupied by the trajectories of the expansion / contraction arms 400a,..., 400e, 400i, 400e 'can be reduced, so that the direction in the branch pipe such as the cheese pipe T can be easily changed.

Further, the expansion / contraction arms 400b,..., 400e, 400i, 400e ′ are provided with fixing rings 224c to 224e, 224e ′ provided at two locations on the advancing direction side in the axis O direction and the retreating walking side. Since the attached expansion / contraction arms 400b,..., 400e, 400i, 400e ′ are opposite in the direction of the axis O, the space occupied by the movement trajectory of the expansion / contraction arms 400b,..., 400e, 400i, 400e ′ is reduced. In addition, the ultrasonic inspection apparatuses 100b to 100e, 100i, 100e 'can be stably held in the tube.

The expansion / contraction arms 400a,..., 400e, 400i, 400e ′ are composed of main arm pieces 411a,..., 411e, 411e ′ having wheels 500a,. 412a,..., 412e, 412e ′ form a link mechanism. Thus, the expansion / contraction arm of the

air cylinders

300, 300c, 300d, 300e, 300e ′ can be expanded and contracted by the link mechanism having a simple structure. 400a,..., 400e, 400i, 400e ′ can be linked to the expansion / contraction operation.

Since a part of the ultrasonic probe 710 is disposed in the hollow portion of the hollow rotating member 611, the size of the

ultrasonic inspection apparatus

100, 100a,..., 100e, 100i, 100e ′ is set in the axial direction. It can be made compact.

Since the

air cylinders

300c, 300d, 300e, and 300e ′ have

auxiliary springs

350c, 350d, 350e, and 350e ′ that assist the return from the expansion operation of the expansion and

contraction arms

400c, 400d, 400e, 400i, and 400e ′, The operations of 400c, 400d, 400e, 400i, and 400e ′ become smoother.

The

ultrasonic inspection apparatuses

100, 100a,..., 100e, 100i, 100e ′ are

air cylinders

300, 300c, 300d, 300e, 300e ′ whose telescopic parts are driven by atmospheric pressure. The danger of contamination, ignition, electric shock, etc. in the pipe is avoided, and expansion / contraction operation with a simple structure is possible.

Since the

ultrasonic inspection apparatuses

100, 100a,..., 100e, 100i, and 100e ′ can operate the

air cylinders

300, 300c, 300d, 300e, and 300e ′ by the expansion / contraction control unit 121 after being inserted into the tube, the expansion / contraction arm can be remotely operated. Can be scaled freely.

The

ultrasonic inspection apparatuses

100, 100a,..., 100e, 100i, and 100e 'can accurately determine the circumferential position of the tube inner wall L to be inspected by ultrasonic waves by including the rotation sensor 770.

According to the layer thickness test using the

ultrasonic inspection apparatuses

100, 100a,..., 100e, 100i, 100e ′ and the layer thickness test apparatuses 100j, 100k, the lining in which the cement-containing layer 920 is lined on the inner peripheral surface of the metal tube 910. The tube 900 is a measurement object, and the transmitted wave R is detected by the detection unit 700 of the

ultrasonic inspection apparatuses

100, 100a,..., 100e, 100i, 100e ′ provided in the composite pipe, and the probes of the layer thickness test apparatuses 100j, 100k. Since it is transmitted from the ultrasonic probe 710 of the parts 700j and 700k, the layer thickness test can be performed in a state where the lining pipe 900 is embedded and the water W is filled therein. For this reason, it is possible to perform a layer thickness test without performing a cutting operation.

According to the layer thickness test using the

ultrasonic inspection apparatuses

100, 100a,..., 100e, 100i, 100e ′ and the layer thickness test apparatuses 100j, 100k, the transmitted wave R is perpendicular to the inner surface of the cement-containing layer 920. The transmission can be performed so as to scan the entire inner circumference of the lining pipe 900 while maintaining the positional relationship of the transmission. Therefore, the thickness of the entire circumference of the metal tube 910 can be tested.

According to the layer thickness test using the

ultrasonic inspection apparatuses

100, 100a, ..., 100e, 100i, 100e 'and the layer thickness test apparatuses 100j, 100k, the frequency of the ultrasonic wave (transmitted wave R) transmitted in the transmission process is When it is 1 MHz or more and 9 MHz or less, it is easy to accurately obtain the thickness of the metal tube 910.

According to the layer thickness test using the

ultrasonic inspection apparatuses

100, 100a,..., 100e, 100i, 100e ′ and the layer thickness test apparatuses 100j, 100k, the thickness D of the aqueous medium interposed in the transmission process is 5 mm or more and 60 mm or less. Therefore, the transmitted wave R is easily transmitted through the metal tube 910, and the reflected wave RB is easily obtained in a highly sensitive state.

According to the layer thickness test using the

ultrasonic inspection apparatuses

100, 100a,..., 100e, 100i, 100e ′ and the layer thickness test apparatuses 100j, 100k, the test object is a metal pipe 910 represented by a cast iron pipe. Since the lining pipe 900 is lined, high versatility can be realized.

The

ultrasonic inspection apparatuses

100, 100a,..., 100e, 100i, 100e ′ and the layer thickness test apparatuses 100j, 100k include a detection unit 700, probe units 700j, 700k, a detection unit 700, and a probe unit for transmitting ultrasonic waves. The expansion /

contraction arm

400, 400a,..., 400e, 400i, 400e ′, the separation portion 400j that separates the head portion of 700j, 700k and the surface of the cement-containing layer 920, and the waveform of the reflected wave intensity with respect to the ultrasonic wave propagation time are acquired. Since the waveform acquisition unit 150 and the determination unit 160 that determines whether or not the number of reflected wave peaks in the waveform is 3 or more are included, the waveform acquisition unit 150 includes at least the peaks of the first reflected waves RI1 and RB1. When (for example, the peak pattern in FIG. 32) is observed, the metal tube 910 has a thickness that allows thickness measurement. It can be determined that that. In this case, the thickness calculator 170 can accurately acquire the thickness of the metal tube 910 by multiplying the detection time difference between the peak of the first reflected wave RB1 and the peak of the first reflected wave RI1 by the speed of sound. .

In the

ultrasonic inspection apparatuses

100, 100a,..., 100e, 100i, 100e ′, and the layer thickness test apparatus 100j, the detection unit 700 and the probe unit 700j can rotate inside the lining tube 900 about the axis of the lining tube 900 as a rotation axis. Therefore, the thickness of the entire circumference of the metal tube 910 can be tested.

The

ultrasonic inspection apparatuses

100, 100a,..., 100e, 100i, 100e ′, and the layer thickness test apparatus 100k are configured such that the detection unit 700 and the probe unit 700k are provided at the axis of the lining tube 900, and the cement-containing layer 920. Since the acoustic reflection part 720 and the mirror 720k that refract so as to be incident perpendicularly to the inner surface of the lining tube 900 are provided to be rotatable about the axis of the lining tube 900, the thickness of the entire circumference of the metal tube 910 Can be tested.

[Correspondence Relationship Between Each Part in Embodiment and Other Examples and Each Component in Claim]
In the present invention, the

ultrasonic inspection apparatuses

100, 100a,..., 100e, 100i, 100e ′ correspond to “ultrasonic inspection apparatuses”, the expansion / contraction control unit 121 corresponds to “extension control unit”, 200a,..., 200e, 200i, 200e ′ correspond to “shaft portions”, the connecting

members

220, 220a,..., 220e correspond to “outer peripheral portions”, and the

air cylinders

300, 300c, 300d, 300e, 300e ′. Corresponds to the “expandable part”, the rod 311, the

movable parts

321c and 321d, and the piston 321e correspond to the “movable part”, and the

auxiliary springs

350c, 350d, 350e, and 350e ′ correspond to the “auxiliary spring”. The

arms

400, 400a,..., 400e, 400i, 400e 'correspond to "expansion / contraction arms", and the main arm pieces 411a, ..., 411e, 411e' correspond to "long arms. The link arm pieces 412a,..., 412e, 412e ′ correspond to “short arm pieces”, and the

wheels

500, 500a,..., 500e, 500i, 500e ′ correspond to “running parts” and are hollow. The shaft motor 610 corresponds to a “hollow shaft motor”, the hollow rotating member 611 corresponds to a “hollow rotating member”, the non-rotating member 612 corresponds to a “non-rotating member”, and the ultrasonic probe 710 It corresponds to an “acoustic probe”, the acoustic reflection part 720 corresponds to an “acoustic reflection part”, the one-turn sensor 770 corresponds to a “rotation sensor”, the position marker 771 corresponds to a “position marker”, and the sensor 772 Corresponds to a “sensor for detecting a position marker”, the housing parts 800 and 800 i correspond to “housing parts”, the free spaces S, Sa,..., Se correspond to “accommodating parts”, and the axis O is “ Is equivalent to Traveling direction F corresponds to the "direction of travel".

Further, the metal pipe 910 corresponds to a “metal layer”, the cement-containing layer 920 corresponds to a “porous layer”, the lining pipe 900 corresponds to a “multilayer body”, and the water W corresponds to a “water medium”. The boundary surface Li between the cement-containing layer and the metal tube corresponds to “the boundary surface between the metal layer and the porous layer”, and the outer surface Lb of the metal tube is “the surface of the metal layer opposite to the porous layer” ”, The transmitted wave R corresponds to“ transmitted ultrasonic wave ”, the first reflected wave RI1 corresponds to“ first interface reflected wave ”, and the first reflected wave RB1 corresponds to“ first outer surface reflected wave ”. The inner peripheral surface Ls corresponds to the “inner peripheral surface”, and the layer thickness test apparatus 100j corresponds to the “layer thickness test apparatus”.

Hereinafter, the present invention will be specifically described with reference to examples. However, the present invention is not limited to the following examples.

JWWA A107, A113 predetermined mortar lining ductile cast iron pipe (mortar lining layer thickness is about 7 mm) was prepared, and a part of the metal was thinned to prepare a sample pipe. The sample tube used in Examples 1 to 7 has a nominal diameter of 250. The thinning process was performed by counterboring, and the flat bottom surface of the counterbored hole with a diameter of 20 mm was defined as the thinned part. As for the thickness reduction of the thinned portion, the metal thickness is 50% of the healthy portion. The layer thickness test was performed by filling the sample tube with water and inserting the layer thickness test apparatus 100j.

[Example 1]
In this example, the layer thickness test was performed with the transmission frequency of 1.0 MHz, the characteristics of the ultrasonic probe being the straight type, and the water distance (distance D in FIGS. 27 and 29) being 15 mm. The oscillogram obtained for the healthy part is shown in FIG. 36 (a), and the oscillogram obtained for the thinned part is shown in FIG. 36 (b). 36 (a) and 36 (b), the horizontal axis indicates the relative value of the layer thickness based on the propagation time, and the vertical axis indicates the relative intensity of the signal. S represents the peak of the reflected wave reflected on the inner peripheral surface of the cement-containing layer, I represents the first reflected wave first reflected at the interface between the cement-containing layer and the metal tube, and B ₁ and F represents the first reflected wave first reflected on the outer surface of the metal tube. B ₂ is a second reflected wave reflected again on the second outside surface of the metal pipe by first reflected wave is reflected at the boundary surface. The same applies to the subsequent oscillograms.

[Example 2]
A layer thickness test was performed in the same manner as in Example 1 except that the transmission frequency was changed to 2.25 MHz. FIG. 37 (a) shows the oscillogram obtained for the healthy part, and FIG. 37 (b) shows the oscillogram obtained for the thinned part.

[Example 3]
A layer thickness test was performed in the same manner as in Example 1 except that the transmission frequency was changed to 3.5 MHz. The oscillogram obtained for the healthy part is shown in FIG. 38 (a), and the oscillogram obtained for the thinned part is shown in FIG. 38 (b).

[Example 4]
A layer thickness test was performed in the same manner as in Example 1 except that the transmission frequency was changed to 5.0 MHz. The oscillogram obtained for the healthy part is shown in FIG. 39 (a), and the oscillogram obtained for the thinned part is shown in FIG. 39 (b).

[Example 5]
A layer thickness test was performed in the same manner as in Example 1 except that the transmission frequency was changed to 7.5 MHz. The oscillogram obtained for the healthy part is shown in FIG. 40 (a), and the oscillogram obtained for the thinned part is shown in FIG. 40 (b).

[Example 6]
A layer thickness test was performed in the same manner as in Example 1 except that the transmission frequency was changed to 10 MHz. FIG. 41 (a) shows the oscillogram obtained for the healthy part, and FIG. 41 (b) shows the oscillogram obtained for the thinned part.

[Example 7]
A layer thickness test was conducted in the same manner as in Example 1 except that the transmission frequency was changed to 2.25 MHz and the characteristics of the ultrasonic probe were of the focus type. The oscillogram obtained for the healthy part is shown in FIG. 42 (a), and the oscillogram obtained for the thinned part is shown in FIG. 42 (b).

[Reference Example 1]
Prepare a test piece of mortar-lined ductile cast iron pipe (half pipe of sample pipe with nominal diameter of 250), and change the water distance (corresponding to distance D in FIGS. 27 and 29) in the range of 10 mm or more and 200 mm or less. And the measurement sensitivity was evaluated. The equipment used is an ultrasonic flaw detector epoch 4 manufactured by Olympus, and the probe has a focus type, a transmission frequency of 2.25 MHz, a vibrator diameter of 12.7 mm, and a focusing point of 50.8 mm. The evaluation of the measurement sensitivity was based on the sensitivity obtained by adjusting the bottom echo detected when the water distance was set to 10 mm to 80% on the display. FIG. 43 shows the change in echo height with respect to the water distance.

The results of measuring the water distance from 10 mm to 60 mm in 10 mm increments and the water distance from 60 mm to 200 mm in 20 mm increments were all good in sensitivity. As shown in FIG. 43, it was found that the bottom echo was high and the sensitivity was good particularly in the range of the water distance of 10 mm to 100 mm. On the other hand, in the range of more than 100 mm and not more than 200 mm, the bottom echo gradually decreased and the sensitivity tended to decrease. However, when the water distance of 50 mm where the sensitivity is particularly good is compared with the case of the water distance of 200 mm where the sensitivity is the lowest, the sensitivity difference is 6 dB, which does not greatly affect the measurement.

[Example 8]
A healthy pipe of a mortar-lined ductile cast iron pipe (nominal diameter 250) of JWWA A107, A113 was prepared, and a part of the metal was thinned to prepare a plurality of sample pipes having different thinning degrees. The thinning process was performed by counterboring, and the flat bottom surface of the counterbored hole with a diameter of 20 mm was defined as the thinned part. The thickness reduction of the metal thickness in the thinned portion of the sample tube is 30%, 50%, 60%, and 75% of the healthy portion, respectively. A layer thickness test was performed on the healthy part and the thinned part. The layer thickness test was performed by filling the sample tube with water and using the layer thickness test apparatus 100j under the conditions of a transmission frequency of 2.25 MHz, using a focal probe, and a water distance of 45 mm.

FIG. 44 shows the relationship between the metal thickness measured by the layer thickness test (water immersion method) and the actual metal thickness. As shown in FIG. 44, the measurement error was about 0.1 mm for the thinning, indicating the accuracy of the layer thickness test of the present invention.

[Example 9]
A mortar ductile cast iron pipe (nominal diameter 150), which has passed 27 years after laying, was obtained, and a layer thickness test was conducted under the conditions of a transmission frequency of 2.25 MHz, using a focal probe, and a water distance of 45 mm.
FIG. 45 shows an oscillogram obtained by the layer thickness test. As shown in FIG. 45, a good oscillogram was obtained as in the case where the layer thickness test was performed on the healthy pipe (Example 1 to Example 8).

[Example 10]
A mortar ductile cast iron pipe (nominal diameter 150) 1 m, which has passed 27 years after laying, was obtained, and further subjected to artificial thinning of 2.0 mm and 3.0 mm to prepare a sample pipe. The layer thickness test was performed under the conditions in Example 5 by filling the sample tube with water and inserting the layer thickness test apparatus 100j. In this example, the rotational speed of the motor accommodated in the cylindrical casing 210j was set to 60 rpm, and the ultrasonic probe 710 was rotated along the circumferential direction of the inner peripheral surface of the sample tube.

FIG. 46 shows the result of the thinning evaluation of the sample tube according to this example. In FIG. 46, the horizontal axis indicates the rotational distance (mm) in the circumferential direction, and the vertical axis indicates the thickness reduction (mm). The rotational distance in the circumferential direction indicates the circumferential distance of the outer peripheral surface of the sample tube. As shown in FIG. 46, natural thinning of 1.4 mm is observed at a rotational distance of 55 mm, artificial thinning of 2.0 mm is observed at a rotational distance of 80 mm, and 3.0 mm at a rotational distance of 200 mm. Artificial thinning was observed.

[Example 11]
A mortar-lined ductile cast iron pipe (nominal diameter 250) having an original wall thickness of 7.7 mm was subjected to a layer thickness test under the conditions of a transmission frequency of 2.25 MHz, a focus type probe, and a water distance of 45 mm. FIG. 47 shows the obtained oscillogram. As FIG. 47 shows, since the detected peak was two, it turned out that the cast iron part of the pipe | tube used for the layer thickness test has remarkably thinned. Actually, when the thickness of the cast iron portion of the pipe subjected to the layer thickness test was directly measured, it was 1.9 mm, and the thickness reduction rate (thickness standard) was 75%.

[Example 12]
A mortar ductile cast iron pipe (nominal diameter 200), which has passed 50 years after laying, was subjected to a layer thickness test under the conditions of a transmission frequency of 2.25 MHz, a focus type probe, and a water distance of 45 mm. FIG. 48 shows the obtained oscillogram. As FIG. 48 shows, since the detected peak was one, it turned out that the lining layer of the pipe | tube used for the layer thickness test has deteriorated notably. In fact, the mortar porosity, cement weight ratio, and calcium concentration were directly measured on the lining portion of the tube subjected to the layer thickness test.

(Measurement method of porosity)
As an X-ray CT system, μB3500 manufactured by Matsusada Precision Co., Ltd. was used, and the lining layer was converted to 3D under measurement conditions of 300 data / 360 ° (taken 300 transmission images per rotation). The porosity was calculated using VG Studio (Volume Graphics) CTX / defect extraction option as dedicated analysis software.

(Measurement method of cement weight ratio)
First, the specimen in the mortar layer was dried at 85 ° C. for 1 hour with a drier, and the dried specimen was crushed into small pieces with a hammer. About 10 g of a sample was weighed into a crucible weighed after drying, 50 ml of 15% HCl was added, a large sample piece was crushed with a glass rod, and sonicated (10 min). The immersion state was maintained for 2 days, and then the specimen was transferred to a weighed 50 ml centrifuge tube. Centrifugation was performed at 3000 rpm for 5 min.

The solid was washed with pure water until neutral (centrifugation 3000 rpm, 2 min x 7 to 10 times), and the solid was dried together with the centrifuge tube in a gear oven (50 ° C.). After weighing the whole centrifuge tube, the sand ratio was calculated.

(Calculation method of calcium concentration)
The supernatant after the above centrifugation treatment was sampled and subjected to ICP analysis (inductively coupled plasma emission spectroscopy). The measurement conditions for ICP analysis are as follows.
・ High frequency output 1.2 kw ・ Spray chamber quartz cyclone chamber ・ Plasma gas flow rate 15 L / min ・ No argon humidifier used ・ Auxiliary gas flow rate 1.5 L / min ・ Analysis wavelength as shown below ・ Carrier gas flow rate 0.9 L / min ・ Integration time 3 seconds, torch quartz torch, 5 repetitions, nebulizer coaxial glass nebulizer, no internal standard correction, ICP emission analysis (SII nanotechnology SPS5100) 2-point qualitative analysis

As a result of the measurement, the mortar porosity was 1.13%, the cement weight ratio was 18% by weight, and the calcium concentration was 15,782 ppm.

[Reference Example 2]
As a lining layer of a ductile cast iron pipe, a sample pipe (nominal diameter 250) similar to that of Example 1 was prepared except that an epoxy resin powder coating layer (about 2 mm) was coated instead of the mortar lining layer. A layer thickness test was performed on the sample tube using the same equipment as in Reference Example 1 with a water distance of 15 mm. FIG. 49A shows the oscillogram obtained for the healthy part, and FIG. 49B shows the oscillogram obtained for the thinned part.

[Reference Example 3]
Prepare a test piece of mortar-lined ductile cast iron pipe (φ270, total thickness 7mm, halved sample pipe with mortar lining heat 5m), and water distance D (corresponding to distance D in FIGS. 27 and 29) of 10mm or more The oscillogram was acquired by changing within a range of 200 mm or less, and the measurement sensitivity was evaluated. The equipment used is an ultrasonic flaw detector epoch 4 manufactured by Olympus, and the probe has a focus type (PF = R80), a transmission frequency of 1.8 MHz, and a vibrator diameter of 12.7 mm. The evaluation of the measurement sensitivity was based on the sensitivity obtained by adjusting the bottom echo detected when the water distance D was set to 10 mm to 80% on the display. The change in echo height H with respect to water distance D is shown in FIG.

The results of measuring the water distance from 10 mm to 60 mm in 10 mm increments and the water distance from 60 mm to 200 mm in 20 mm increments were all good in sensitivity. As shown in Table 1, as the water distance D increases, the bottom echo gradually decreases and the sensitivity tends to decrease. However, when the water distance is 10 mm where the sensitivity is the best and the water distance is 180 mm, the sensitivity difference is 6 dB, the water distance where the sensitivity is the best 10 mm, and the water distance where the sensitivity is the lowest. When compared with the case of 200 mm, the sensitivity difference was 7 dB, and as in Reference Example 1, the measurement did not have a significant effect.

[Example 13]
A test piece of the same mortar-lined ductile cast iron pipe as in Reference Example 3 was prepared, and a part of the metal was thinned to prepare a sample piece. The thinning process was performed by counterboring, and the flat bottom surface of the counterbored hole with a diameter of 20 mm was defined as the thinned part. As for the thickness reduction of the thinned portion, the metal thickness is 50% of the healthy portion. The layer thickness test was performed by filling the sample piece with water and inserting the layer thickness test apparatus 100j.

In the present embodiment, the same equipment as in Reference Example 3 (Olympus ultrasonic flaw detector epoch 4, the characteristics of the probe are the focus type (PF = R80), the transmission frequency is 1.8 MHz, and the vibrator diameter is 12.7 mm. )) And the water distance D was set to 10 mm, and the layer thickness test was performed. The oscillogram obtained for the healthy part is shown in FIG. 50 (a), and the oscillogram obtained for the thinned part is shown in FIG. 50 (b). 50 (a) and 50 (b), the horizontal axis indicates the relative value of the layer thickness based on the propagation time, and the vertical axis indicates the relative intensity of the signal. S represents the peak of the reflected wave reflected on the inner peripheral surface of the cement-containing layer, I represents the first reflected wave first reflected at the interface between the cement-containing layer and the metal tube, and B1 and F Represents the first reflected wave first reflected on the outer surface of the metal tube (the same applies to the following oscillogram).

[Example 14]
A layer thickness test was performed in the same manner as in Example 13 except that the transmission frequency of the probe was changed to 2.25 MHz. The oscillogram obtained for the healthy part is shown in FIG. 51 (a), and the oscillogram obtained for the thinned part is shown in FIG. 51 (b).

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

Claims

The shaft,
A plurality of expansion / contraction arms projecting from the outer peripheral portion of the shaft portion and capable of expanding / contracting in a radial direction around the axis of the shaft portion;
A traveling part provided on the expansion / contraction arm;
A telescopic part for expanding and contracting the expansion / contraction arm;
An expansion / contraction control unit for controlling the expansion / contraction part;
A motor directly or indirectly fixed to the shaft portion;
An ultrasonic probe arranged to emit ultrasonic waves in the axial direction;
An ultrasonic inspection apparatus comprising: an acoustic reflection unit configured to reflect the ultrasonic wave transmitted from the ultrasonic probe in the radial direction from the axial direction.
The ultrasonic inspection apparatus according to claim 1, wherein the extendable part has a movable part, and the movable part is provided so as to move in an axial direction of the shaft part.
2. The ultrasonic inspection apparatus according to claim 1, wherein the expansion / contraction portion is disposed on the outer peripheral portion of the shaft portion such that the expansion / contraction portion expands and contracts in an axial direction of the shaft portion.
The ultrasonic inspection apparatus according to claim 1 or 2, wherein the stretchable part constitutes at least a part of the shaft part.
The expansion / contraction arm has a receiving portion;
The ultrasonic inspection apparatus according to claim 1, wherein when the expansion / contraction arm is contracted, the expansion / contraction part is accommodated in the accommodation part.
Including at least a housing portion for housing the motor;
The ultrasonic inspection apparatus according to any one of claims 1 to 5, wherein when the expansion / contraction arm is most contracted, the entire expansion / contraction arm overlaps the projection of the housing portion in the axial direction. .
The expansion / contraction arms arranged at the one end side, with the base ends of the plurality of expansion / contraction arms being axially attached at two locations on the shaft portion on the one end side and the other end side in the axial direction. The ultrasonic inspection apparatus according to claim 1, wherein the expansion / contraction arm disposed on the other end side is opposite in the axial direction.
8. The link mechanism according to claim 1, wherein the expansion / contraction arm has a link mechanism configured to include a long arm piece having the traveling portion disposed at a tip thereof and a short arm piece shorter than the long arm piece. The ultrasonic inspection apparatus according to item.
The motor is a hollow shaft motor including a hollow rotating member and a non-rotating member surrounding the hollow rotating member, and at least a part of the ultrasonic probe is disposed in a hollow portion of the hollow rotating member. The ultrasonic inspection apparatus according to any one of claims 1 to 8.
The ultrasonic inspection apparatus according to any one of claims 1 to 9, wherein the expansion / contraction section includes an auxiliary spring that assists the operation of the expansion / contraction arm.
The ultrasonic inspection apparatus according to claim 1, wherein the expansion / contraction part is driven by atmospheric pressure.
The ultrasonic inspection apparatus according to claim 11, wherein the expandable portion is an air cylinder.
The ultrasonic inspection apparatus according to any one of claims 1 to 12, including a position marker provided in the motor or the acoustic reflection unit, and a sensor for detecting the position marker.
An ultrasonic inspection method for performing an ultrasonic inspection inside a pipe using the ultrasonic inspection apparatus according to any one of claims 1 to 13.
The tube is a multilayer body including a metal layer and a porous layer provided on the surface of the metal layer, and the metal layer side from the porous layer side under the condition that an aqueous medium is interposed An ultrasonic wave is transmitted in the direction toward the surface, and at least the peak of the first interface reflected wave first reflected at the interface between the metal layer and the porous layer, and the opposite side of the metal layer from the porous layer The ultrasonic inspection method according to claim 14, wherein the thickness of the metal layer is calculated based on a detection time difference from a peak of the first outer surface reflected wave first reflected on the surface.