Pipe inspection equipment

Abstract

When an inspection head with a V-shaped groove is brought into contact with the pipe to be inspected, the deterioration of the inspection accuracy by the probe due to the cross-sectional shape of the pipe to be inspected is suppressed. [Solution] The pipe inspection device 10 includes an inspection head 12 positioned at the tip of a long member 11. The inspection head 12 has a head body 22 having a pair of contact surfaces 25, 26 that form a V-shaped groove, and a probe 21 having a probe portion 21a at its tip and positioned between the pair of contact surfaces 25, 26. The probe 21 is supported by the head body 22 in a way that allows the relative orientation of the probe portion 21a with respect to the head body 22 to be variable.

Description

Technical Field

[0001] The present invention relates to a pipe inspection instrument.

Background Art

[0002] Conventionally, as disclosed in Patent Documents 1 and 2 below, as a pipe inspection instrument for a device having a plurality of pipes such as a boiler, an inspection instrument used for measuring the wall thickness of each pipe is known. As shown in FIG. 10, the pipe inspection instrument disclosed in Patent Document 1 includes a positioning member 92 having a pair of block pieces 91, 91 and forming a V-shaped cross section, and an ultrasonic probe 93 located at the bottom of the V-groove of the positioning member 92. A wall thickness measuring unit 94 having the ultrasonic probe 93, and an arm member 96 whose tip is connected to a joint member 95 to which the wall thickness measuring unit 94 is attached. This inspection instrument is set so that the valley surface of the V-groove formed by the pair of block pieces 91, 91 abuts on the inspection target pipe 98 (see FIG. 11). In this state, ultrasonic waves are transmitted from the ultrasonic probe 93 toward the inspection target pipe 98 and reflected waves are received, whereby the wall thickness of the inspection target pipe 98 can be measured. Note that the positioning member 92 having the pair of block pieces 91, 91 forming the valley surface of the V-groove is also disclosed in Patent Document 2.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the pipe inspection device disclosed in Patent Document 1, the ultrasonic probe 93 is positioned in the center of the V-groove of the positioning member 92. Therefore, when the positioning member 92 is positioned relative to the axis of the pipe to be inspected 98, the tip of the ultrasonic probe 93 can contact the outer surface of the pipe to be inspected 98 from a direction perpendicular to it. However, the fact that the tip of the ultrasonic probe 93 faces perpendicular to the outer surface of the pipe to be inspected 98 is based on the premise that the cross-section of the pipe to be inspected 98 is formed to be perfectly circular, as shown in Figure 11. However, the cross-section of the pipe to be inspected 98 is not necessarily perfectly circular. For example, it may be deformed due to long-term use, or the outer surface may not be perfectly circular due to thinning or scale buildup. Therefore, as shown in Figure 12, even if the ultrasonic probe 93 is positioned in the center of the V-groove, depending on the cross-sectional shape of the pipe to be inspected 98, the ultrasonic probe 93 may not face perpendicular to the outer surface of the pipe to be inspected 98, which may worsen the inspection accuracy.

[0005] Therefore, the present invention has been made in view of the above-mentioned prior art, and its objective is to suppress the deterioration of inspection accuracy by the probe when an inspection head having a V-shaped groove is brought into contact with a pipe to be inspected, due to the cross-sectional shape of the pipe to be inspected. [Means for solving the problem]

[0006] To achieve the above objective, the pipe inspection device according to the present invention is a pipe inspection device used to inspect a target pipe among a group of pipes in which a plurality of pipes extending in a predetermined direction are arranged at intervals from one another, and comprises a long member and an inspection head disposed at the tip of the long member. The inspection head has a head body having a pair of contact surfaces that form a V-shaped groove, and a probe having a probe section at its tip for detecting the state of the target pipe, and disposed between the pair of contact surfaces. The probe is supported by the head body in such a way that the relative orientation of the probe section with respect to the head body can be varied.

[0007] In the pipe inspection device according to the present invention, the position of the probe relative to the pipe is determined when a pair of contact surfaces come into contact with two locations in the circumferential direction of the pipe to be inspected. At this time, if the cross-section of the pipe to be inspected is a perfect circle, the exploration part located at the tip of the probe will be oriented perpendicular to the outer surface of the pipe to be inspected, and the pipe to be inspected can be explored with the probe in this state. On the other hand, if the cross-section of the pipe to be inspected is not a perfect circle, the exploration part of the probe may not be oriented perpendicular to the outer surface of the pipe to be inspected. Even in that case, it is possible to change the orientation of the exploration part by having the exploration part come into contact with the pipe to be inspected, so that the exploration part of the probe can be oriented perpendicular to the outer surface of the pipe to be inspected. Therefore, depending on the cross-sectional shape of the pipe to be inspected, it is possible to deal with cases where the exploration part of the probe does not become oriented perpendicular to the outer surface of the pipe to be inspected simply by the pipe to be inspected coming into contact with the pair of contact surfaces. Thus, deterioration of the inspection of the pipe to be inspected by the probe can be suppressed.

[0008] The pipe inspection device may further include an operating unit and a rocking mechanism that changes the relative orientation of the probe with respect to the head body by operation of the operating unit. In this embodiment, the operating unit can be used to change the orientation of the probe via the rocking mechanism, thereby allowing the probe of the probe to face perpendicular to the outer surface of the pipe being inspected. Therefore, depending on the cross-sectional shape of the pipe being inspected, it is possible to address cases where the probe's probe does not face perpendicular to the outer surface of the pipe being inspected simply by contacting the pipe with a pair of contact surfaces. Thus, deterioration of the inspection of the pipe being inspected by the probe can be suppressed.

[0009] The oscillation mechanism may include a pivot point that defines the pivot point of the probe, and a pressing part configured to apply a pressing force to the probe at a position away from the pivot point and in a direction adjacent to the pair of contact surfaces. In this case, the probe may receive the pressing force from the pressing part and change the relative orientation of the probe with respect to the head body, using the pivot point as the pivot point.

[0010] In this embodiment, pressing force is applied to the probe by the pressing part in response to the operation of the operating part. As a result, the probe's relative orientation to the head body changes, with the pivot point acting as the pivot point. Therefore, the orientation of the probe can be changed when the pipe under inspection is in contact with the pair of contact surfaces and the probe's position relative to the pipe under inspection is determined. At this time, the direction of the probe's oscillation is in the direction of the adjacent pair of contact surfaces (i.e., the direction perpendicular to the axial direction of the pipe under inspection and along the circumferential direction of the pipe under inspection). Therefore, if the cross-section of the pipe under inspection that is in contact with the pair of contact surfaces is not a perfect circle, the orientation of the probe can be changed to a more appropriate direction.

[0011] The pressing portion may include a lever provided to rotate in response to the operation of the operating portion, and a rocking plate configured such that a pressing force is applied to the probe by the pair of contact surfaces moving in adjacent directions in conjunction with the rotation of the lever.

[0012] In this embodiment, when the lever rotates in response to the operation of the control unit, the oscillating plate moves in one direction in conjunction with this rotation. The probe, which receives pressure from the oscillating plate, then changes the orientation of its exploration section, using the pivot point as the pivot point. At this time, the orientation of the probe's exploration section changes as the oscillating plate moves in a direction in which the pair of contact surfaces are adjacent, so the direction of the probe's oscillation is in the direction in which the pair of contact surfaces are adjacent. Therefore, when the cross-section of the pipe under inspection that contacts the pair of contact surfaces is not a perfect circle, the orientation of the exploration section can be changed to a more appropriate direction. Moreover, the oscillation mechanism can be constructed with a simple mechanism that converts rotational motion into linear motion.

[0013] The inspection head may be configured to be rotatable with respect to the elongated member so as to change the connection angle with respect to the elongated member. In this case, the pipe inspection device may further include a biasing means for stabilizing the inspection head in a neutral position where the connection angle of the inspection head with respect to the elongated member is a predetermined angle. The biasing means may include a first spring member that biases the inspection head in a first orientation in the rotational direction, and a second spring member provided to connect the operating unit and the swing mechanism and biasing the inspection head in a second orientation opposite to the first orientation in the rotational direction.

[0014] In this embodiment, the connection angle of the inspection head to the elongated member can be changed according to the circumferential position of the pipe to be inspected, thus enabling inspection at various circumferential positions of the pipe to be inspected. Moreover, since the second spring member, which constitutes the biasing means for stabilizing the inspection head in a neutral position, is configured to connect the operating unit and the oscillating mechanism, the operation of oscillating the inspection head is performed using the second spring member. Therefore, an increase in the number of parts is suppressed.

[0015] The pipe inspection device does not necessarily have to include the operating unit and the swinging mechanism. In this case, the inspection head may be configured to be rotatable with respect to the elongated member so as to change the connection angle with respect to the elongated member. The pipe inspection device may also further include a biasing means for stabilizing the inspection head in a neutral position where the connection angle of the inspection head with respect to the elongated member is a predetermined angle. The biasing means may include a first spring member that biases the inspection head in a first direction in the rotational direction, and a second spring member that biases the inspection head in a second direction opposite to the first direction in the rotational direction.

[0016] In this aspect, since the connection angle of the inspection head with respect to the long member can be changed according to the circumferential position of the inspection target pipe, inspection can be performed at various circumferential positions of the inspection target pipe. Moreover, since the inspection head is maintained in a neutral posture unless it is subjected to an external force, it is possible to prevent the work from becoming complicated when the inspection head is sequentially aligned with a plurality of inspection heads.

[0017] The pipe inspection instrument may further include a display unit that displays an output corresponding to the signal received from the exploration unit.

[0018] In this aspect, the user of the pipe inspection instrument can operate the operation unit while referring to the output displayed on the display unit. Therefore, it is possible to assist the operation for setting the exploration unit of the probe in an appropriate direction, and thus the operation can be facilitated.

[0019] Magnets may be provided along the pair of abutting surfaces, respectively. In this aspect, the inspection target pipe abutting on the abutting surface can be adsorbed by the magnets. Therefore, during inspection, the inspection head can be held so as not to be displaced with respect to the inspection target pipe. Therefore, stable inspection results can be obtained.

Advantages of the Invention

[0020] As described above, according to the present invention, when the inspection head having a V-shaped groove is abutted against the inspection target pipe, it is possible to suppress deterioration of the inspection accuracy by the probe depending on the cross-sectional shape of the inspection target pipe.

Brief Description of the Drawings

[0021] [Figure 1] (a)(b) It is a figure which shows the whole structure of the piping inspection instrument which concerns on embodiment. [Figure 2] It is a figure for demonstrating the case where a piping inspection instrument is used for an apparatus which has a pipe group, such as a boiler. [Figure 3] It is the schematic diagram at the time of the base side part of a long member being comprised so that expansion-contraction is possible. [Figure 4]This is a diagram showing the inspection head as viewed from above. [Figure 5] This is a cross-sectional view showing the inspection head as viewed from the side. [Figure 6] This is a perspective view of the cylindrical member. [Figure 7] This is a diagram for explaining the configuration of the swing mechanism. [Figure 8] (a) shows the state when the lever is in the initial position without rotating, (b) shows the state when the swing plate has moved forward, and (c) shows the state when the swing plate has moved backward. [Figure 9] This is a cross-sectional view showing the inspection head of the pipe inspection instrument according to another embodiment as viewed from the side. [Figure 10] This is a diagram schematically showing a conventional pipe inspection instrument. [Figure 11] This is a diagram for explaining the orientation of the ultrasonic probe with respect to the outer surface of the inspection target pipe when the cross-section of the inspection target pipe is a perfect circle. [Figure 12] This is a diagram for explaining the orientation of the ultrasonic probe with respect to the outer surface of the inspection target pipe when the cross-section of the inspection target pipe is other than a perfect circle.

Mode for Carrying Out the Invention

[0022] Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

[0023] As shown in FIGS. 1(a) and 1(b), the pipe inspection instrument 10 according to the present embodiment is an instrument for performing a wall thickness inspection of a metal pipe using ultrasonic waves, and can be used for inspecting a device having a large number of pipes such as a boiler. As shown in FIG. 2, in a boiler or the like, a pipe group PG in which a large number of pipes P are arranged in parallel with each other is provided. Each pipe P is arranged so as to be arranged in the vertical and horizontal directions, and has a so-called checkerboard arrangement. An inspection head 12 is provided at the tip of the pipe inspection instrument 10, and until this inspection head 12 reaches the pipe P (inspection target pipe SP) to be inspected, the pipe inspection instrument 10 is inserted into the gap G between the pipes P downward from above, for example, of this pipe group PG.

[0024] As shown in Figures 1(a) and 1(b), the pipe inspection device 10 comprises a long member 11 and an inspection head 12 positioned at the tip of the long member 11. The long member 11 is composed of a linearly extending member, with its base end 11a functioning as a handle for the user to hold and its tip functioning as a part to support the inspection head 12.

[0025] The elongated member 11 has a rod-shaped base portion 13 having a base end 11a that functions as a handle, and a tip portion 14 connected to the base portion 13 and to which an inspection head 12 is attached. The base portion 13 may be configured to be extendable and retractable by having multiple members arranged in a nesting manner, as shown in Figure 3.

[0026] As shown in Figure 1(a), the front section 14 has a pair of elongated flat plates 14a arranged parallel to each other with a gap between them, and a plurality of pin members 14b spanning between the elongated flat plates 14a. The plurality of pin members 14b are provided to increase the rigidity of the elongated flat plates 14a (front section 14), but some of the pin members 14b also have other functions.

[0027] The first pin member 14c, which is one of the multiple pin members 14b, also functions as a support member for the inspection head 12. As shown in Figure 4, the inspection head 12 is positioned between the elongated flat plates 14a, and the inspection head 12 is rotatably supported by the first pin member 14c. That is, the inspection head 12 (head body 22, described later) is rotatable relative to the elongated members 11. Because the inspection head 12 is located between the elongated flat plates 14a, even when the inspection head 12 rotates, interference between the inspection head 12 or the parts connected to the inspection head 12 and the elongated flat plates 14a is prevented.

[0028] One end of a first spring member 15, which is made of a coil spring, is attached to a second pin member 14d, which is one of the multiple pin members 14b. The first spring member 15 connects the second pin member 14d to the rear end of the inspection head 12 (head body 22, which will be described later).

[0029] The first spring member 15 biases the inspection head 12 in a first direction in the rotational direction (counterclockwise direction in Figure 5). The inspection head 12 is also connected to a second spring member 16 which biases the inspection head 12 in a second direction (clockwise direction in Figure 5), which is opposite to the first direction. As a result, when the inspection head 12 is subjected to an external force that causes it to rotate around the first pin member 14c so that its front end (left end in Figure 5) rises, the first spring member 15 applies a tensile force to the inspection head 12 that causes it to rotate in a direction that causes its front end to descend. On the other hand, when the inspection head 12 is subjected to an external force that causes it to rotate around the first pin member 14c so that its front end descends, the second spring member 16 applies a tensile force to the inspection head 12 that causes it to rotate in a direction that causes its front end to rise.

[0030] A biasing means 18 is configured by a first spring member 15 and a second spring member 16 to stabilize the inspection head 12 in a neutral position where the connection angle of the inspection head 12 to the elongated member 11 is a predetermined angle. When the inspection head 12 rotates upward or downward from the neutral position, one of the first spring member 15 and the second spring member 16 stretches, and the biasing means 18 returns the inspection head 12 to the neutral position by its spring elastic force. In this embodiment, the neutral position is the position in which the exploration portion 21a of the probe 21, which will be described later, faces in a direction parallel to the direction in which the elongated member 11 extends (downward in Figure 1(b)), but it is not limited to this.

[0031] As shown in Figure 5, the inspection head 12 includes a probe 21 having a probe section 21a at its tip, and a head body 22 that supports the probe 21.

[0032] The head body 22 has a first main surface 22a on which a pair of contact surfaces 25, 26 are formed, a second main surface 22b facing the opposite side of the first main surface 22a, and a circumferential surface that connects the first main surface 22a and the second main surface 22b to each other. The circumferential surface includes a front end surface 22c, a rear end surface 22d facing the opposite side of the front end surface 22c, and a pair of side surfaces 22e (see Figure 4).

[0033] One end of the first spring member 15 is connected to the rear end surface 22d. The first pin member 14c is inserted through a through hole 24 that penetrates between a pair of side surfaces 22e. The through hole 24 is formed on the pair of side surfaces 22e at a position close to the rear end surface 22d.

[0034] In the example shown in Figure 1(b), the head body 22 is attached to the elongated member 11 with the first main surface 22a facing downwards and the second main surface 22b facing upwards. However, it is also possible to attach the head body 22 to the elongated member 11 with the first main surface 22a facing upwards and the second main surface 22b facing downwards.

[0035] As shown in Figure 5, the pair of contact surfaces 25 and 26 face each other so as to form a V-shaped groove when viewed from the side. The bottom 27 of the groove extends in a direction parallel to the direction in which the first pin member 14c extends. The probe 21 is positioned such that the exploration portion 21a is located in the center of the width direction of this groove.

[0036] A recess is formed in each of the pair of contact surfaces 25 and 26, and a magnet 29 is attached to this recess. The magnet 29 is formed in a flat plate shape, and its main surface is positioned along the contact surfaces 25 and 26. Because the main surface of the magnet 29 is flush with the contact surfaces 25 and 26, when the pipe SP to be inspected comes into contact with the pair of contact surfaces 25 and 26, the magnet 29 can effectively attract the pipe SP to be inspected. Therefore, the inspection head 12 does not shift position relative to the pipe SP to be inspected during inspection. Note that although two magnets 29 are provided on each of the contact surfaces 25 and 26, this is not the only configuration.

[0037] The probe unit 21a of the probe 21 emits ultrasonic waves and receives reflected waves from the pipe SP under inspection. A cable 31 is connected to the base end of the probe 21, and the cable 31 transmits the signal obtained from the reflected waves detected by the probe unit 21a to the control device 33 (Figure 1(b)). The control device 33 includes a display unit 33a that displays an output corresponding to the signal received from the probe unit 21a, that is, an output corresponding to the reflected waves (for example, an output waveform). Note that the probe unit 21a is not limited to a configuration that emits ultrasonic waves, as long as it functions as a part for detecting the state of the pipe SP under inspection.

[0038] The probe 21 is positioned such that its tip, the exploration section 21a, protrudes from the first main surface 22a of the head body 22, while its base protrudes from the second main surface 22b of the head body 22. Furthermore, the probe 21 is pivotably supported by the head body 22. This will be explained in detail below.

[0039] The head body 22 has a mounting hole 35 that penetrates between the first main surface 22a and the second main surface 22b. One end of the mounting hole 35 opens into the bottom 27 of a V-shaped groove. The mounting hole 35 is a through-hole with a circular cross-section having an inner diameter larger than the outer diameter of the probe 21, and is positioned so that the central axis of the mounting hole 35 coincides with the center in the width direction of the bottom 27 of the groove.

[0040] At the end of the mounting hole 35 on the side of the first main surface 22a, a receiving surface 35a is formed, which has a shape in which the inner diameter decreases towards the outside. This receiving surface 35a receives the pivot point 41 of the cylindrical member 43, which will be described later, and supports the probe 21 so as to become the pivot point of the probe 21. In other words, the probe 21 is supported on the head body 22 in a way that allows for variable relative orientation of the exploration section 21a with respect to the head body 22 (or the orientation of the contact surfaces 25, 26).

[0041] The pipe inspection device 10 is equipped with a swing mechanism 40 that changes the relative orientation of the probe 21a with respect to the head body 22 by operating the operating unit 56 (see Figure 1(b)) described later. The swing mechanism 40 has a pivot point 41 that defines the pivot point of the probe 21, and a pressing unit 42 that operates so as to transmit a pressing force to the probe 21 when the orientation of the probe 21a is changed.

[0042] The pivot point 41 is provided on a cylindrical member 43 attached to the probe 21 so as to surround the probe 21. The cylindrical member 43 has an internal thread formed on its inner circumference, and is fixed to the probe 21 by screwing this internal thread into an external thread formed on the outer circumference of the probe 21. Note that the method of fixing the cylindrical member 43 to the probe 21 is not limited to this, and for example, an adhesive may be used.

[0043] As shown in Figure 6, the pivot point 41 is formed in a flange shape at one end of the cylindrical member 43 in the longitudinal direction. The pivot point 41 has an inclined surface that matches the shape of the receiving surface 35a formed in the mounting hole 35. This inclined surface is an annular inclined surface that is sloped so that the outer diameter decreases towards the tip.

[0044] A gap is formed between the outer circumferential surface of the cylindrical member 43 and the inner circumferential surface of the mounting hole 35, and a oscillating spring 45 made of a coil spring is positioned in this gap. The oscillating spring 45 is positioned to surround the cylindrical member 43 and is also positioned in a compressed state between the lid member 46 attached to the second main surface 22b of the head body 22 and the pivot point 41. As a result, the pivot point 41 is pressed against the receiving surface 35a. However, since a gap remains between the oscillating spring 45 and the inner circumferential surface of the mounting hole 35, the probe 21 can tilt with the pivot point 41 as the pivot point.

[0045] As shown in Figure 7, the pressing section 42 includes a lever 48 rotatably attached to the head body 22 and a rocking plate 49 that moves back and forth in conjunction with the rotation of the lever 48 to apply a pressing force to the cylindrical member 43. In this embodiment, the rocking plate 49 is positioned to press the cylindrical member 43, but it may be positioned to press the probe 21 instead.

[0046] The lever 48 is composed of a plate-shaped member extending in one direction, and a pivot shaft portion 48a protrudes from one end of the lever 48, which is inserted into a shaft hole formed in the second main surface 22b of the head body 22. The lever 48 is rotatably supported by the head body 22 at the pivot shaft portion 48a. The direction of rotation of the lever 48 is along the second main surface 22b of the head body 22.

[0047] Furthermore, the lever 48 also has a protruding operating shaft portion 48b to which the aforementioned second spring member 16 is attached. The operating shaft portion 48b protrudes from the lever 48 on the opposite side from the pivot shaft portion 48a at a position that is in a straight line with the pivot shaft portion 48a. Therefore, in response to the operation of the operating part 56 described later, the operating shaft portion 48b rotates around the axis via the second spring member 16, allowing the lever 48 to rotate around the pivot shaft portion 48a.

[0048] The lever 48 is secured from the head body 22 by a fixing block 51. The fixing block 51 is attached to the second main surface 22b of the head body 22 by a bolt 52 that is screwed into a screw hole provided on the second main surface 22b of the head body 22.

[0049] The fixing block 51 has a through hole 51a through which the operating shaft portion 48b of the lever 48 is inserted, and covers one end of the lever 48 from above when the operating shaft portion 48b of the lever 48 is inserted through the through hole 51a. In addition, the fixing block 51 has a notch 51b formed therein so as not to interfere with the lever 48 when the lever 48 is rotated. As a result, the lever 48 can be rotated while preventing it from falling off.

[0050] A oscillating plate 49 is pin-connected to the other end of the lever 48. The direction of movement of the oscillating plate 49 is restricted by a regulating member 54 (see Figure 4) attached to the second main surface 22b of the head body 22. As a result, the rotation of the lever 48 is converted into linear movement of the oscillating plate 49. The regulating member 54 not only restricts the direction of movement of the oscillating plate 49 but also prevents the oscillating plate 49 from detaching from the head body 22.

[0051] The direction of movement of the oscillating plate 49 is the direction connecting the rear end surface 22d and the front end surface 22c of the head body 22, that is, the direction in which the pair of contact surfaces 25 and 26 are adjacent (front-rear direction). For example, when the lever 48 is in its initial position without rotation, the oscillating plate 49 is in an initial position where the exploration section 21a faces perpendicular to the front-rear direction (Figure 8(a)). When the lever 48 is rotated clockwise in Figure 4, the oscillating plate 49 moves forward, pressing the base end portion of the probe 21 on the cylindrical member 43. As a result, the exploration section 21a is tilted slightly toward the rear end surface 22d with respect to the vertical direction (Figure 8(b)). On the other hand, when the lever 48 is rotated counterclockwise in Figure 4, the oscillating plate 49 moves backward, so the exploration section 21a is tilted slightly toward the front end surface 22c with respect to the vertical direction (Figure 8(c)). Therefore, when the lever 48 rotates, the oscillating plate 49 moves forward or backward depending on the direction of rotation.

[0052] The oscillating plate 49 is made of a plate material extending in one direction, and an action portion 49a is formed in the middle portion in the longitudinal direction. The action portion 49a is the part that applies the movement of the oscillating plate 49 to the probe 21, and is made of a through hole or notch through which the probe 21 and the cylindrical member 43 are inserted. The action portion 49a includes a contact surface that contacts the outer circumferential surface of the cylindrical member 43 inserted into the action portion 49a. Therefore, the oscillating plate 49 can move in a direction in which the pair of contact surfaces 25 and 26 are adjacent to each other in conjunction with the rotation of the lever 48, and this movement can apply a pressing force to the probe 21. As a result, the exploration portion 21a of the probe 21 can change its orientation so that the pair of contact surfaces 25 and 26 are adjacent to each other.

[0053] The lever 48 receives an operating force from the operating section 56 (see Figure 1(b)). The operating section 56 is the part used by the user of the pipe inspection device 10 to adjust the direction of the exploration section 21a, and includes a base end portion 56a located near the base end 11a of the elongated member 11. The base end 11a of the elongated member 11 is located outside the pipe group PG even when the elongated member 11 is inserted into the pipe group PG so that the inspection head 12 can reach the pipe SP to be inspected. At this time, the base end portion 56a of the operating section 56 is also located outside the pipe group PG, so the user can operate the operating section 56 from outside the pipe group PG.

[0054] The operating section 56 is composed of a rod-shaped member extending in one direction and is inserted through a ring member 58 provided on the elongated member 11. This holds the operating section 56 in a position along the elongated member 11. The aforementioned cable 31 connected to the probe 21 is also inserted through this ring member 58. The operating section 56 is configured by connecting multiple members to each other, but is not limited to this configuration and may be composed of a single member.

[0055] The tip of the operating section 56 is connected to the second spring member 16 described above. The second spring member 16 is made of a very long coil spring, and the other end of the second spring member 16 is connected to the operating shaft portion 48b of the lever 48. That is, the lever 48 is connected to the operating section 56 via the second spring member 16, and when the rod-shaped operating section 56 is rotated around its axis, the lever 48 rotates around the pivot shaft portion 48a. Furthermore, because the second spring member 16 is made of a very long coil spring, when the inspection head 12 is rotated upward from the neutral position, the second spring member 16 bends, allowing it to follow the change in the posture of the inspection head 12. The second spring member 16 has a length about the same as the front portion 14 of the long member 11, but is not limited to this.

[0056] The method for inspecting the wall thickness of a pipe SP using the pipe inspection device 10 configured as described above will now be explained. First, since scale may be attached to the pipe SP, in that case, the scale attached to the pipe SP is removed using the removal tool shown in the figure. Next, the coupling medium is applied to the surface of the exploration part 21a of the probe 21.

[0057] Subsequently, the user grasps the base end 11a of the elongated member 11 and the base end portion 56a of the operating part 56, and inserts the inspection head 12 into the gap G between pipes in a pipe group PG of a boiler or the like. At this time, the inspection head 12 is inserted into the gap G between pipes P such that the front-rear direction of the inspection head 12 (the direction connecting the front end surface 22c and the rear end surface 22d, the direction in which the inspection head 12 protrudes from the elongated member 11, and the left-right direction in Figure 5) is aligned with the direction in which the pipes P extend.

[0058] When the inspection head 12 reaches the pipe SP to be inspected, the orientation of the inspection head 12 is changed so that its front-to-back direction is perpendicular to the pipe P, and the position of the inspection head 12 is adjusted so that the pair of contact surfaces 25 and 26 contact the pipe SP to be inspected. At this time, the magnets 29 placed on the pair of contact surfaces 25 and 26 attract the pair of contact surfaces 25 and 26 to the pipe SP to be inspected. This determines the position of the pipe SP to be inspected relative to the pair of contact surfaces 25 and 26.

[0059] In this state, the probe 21 scans the pipe SP to be inspected, and at this time, the operating unit 56 is operated while referring to the output displayed on the display unit 33a. That is, the base end portion 56a of the operating unit 56 is rotated around its axis, and the change in output is observed. By operating the operating unit 56, the oscillating plate 49 is displaced forward or backward as the lever 48 rotates, and accordingly the probe 21 changes the orientation of the exploration unit 21a. As a result, the reflected wave received by the exploration unit 21a changes, and the orientation of the exploration unit 21a can be finely adjusted while referring to the output displayed on the display unit 33a.

[0060] Then, the long member 11 is moved from top to bottom or from bottom to top while scanning a desired range of the pipe SP to be inspected, and the minimum wall thickness is measured.

[0061] As described above, in the pipe inspection device 10 according to this embodiment, when the pair of contact surfaces 25 and 26 contact two locations in the circumferential direction of the pipe SP to be inspected, the position of the probe 21 relative to the pipe SP to be inspected is determined. At this time, if the cross-section of the pipe SP to be inspected is a perfect circle, the exploration part 21a located at the tip of the probe 21 will be oriented perpendicular to the outer surface of the pipe SP to be inspected, and the pipe SP to be inspected can be explored by the probe 21 in this state. On the other hand, if the cross-section of the pipe SP to be inspected is not a perfect circle, the exploration part 21a of the probe 21 may not be oriented perpendicular to the outer surface of the pipe SP to be inspected. In that case, by operating the operation unit 56 to change the orientation of the exploration part 21a via the oscillating mechanism 40, it is possible to make the exploration part 21a of the probe 21 oriented perpendicular to the outer surface of the pipe SP to be inspected. Therefore, depending on the cross-sectional shape of the pipe SP to be inspected, it is possible to address cases where the probe 21's exploration portion 21a is not oriented perpendicular to the outer surface of the pipe SP to be inspected simply by the pipe SP coming into contact with the pair of contact surfaces 25 and 26. Thus, deterioration of the inspection of the pipe SP by the probe 21 can be suppressed.

[0062] Furthermore, in this embodiment, in response to the operation of the operating unit 56, a pressing force is applied to the probe 21 by the pressing unit 42 of the oscillating mechanism 40. As a result, the probe 21 changes the relative orientation of the exploration unit 21a with respect to the head body 22, using the pivot point 41 as the pivot point. Therefore, the orientation of the exploration unit 21a can be changed when the pipe SP to be inspected is in contact with the pair of contact surfaces 25 and 26 and the position of the probe 21 relative to the pipe SP to be inspected is determined. At this time, the direction of oscillation of the probe 21 is in the direction in which the pair of contact surfaces 25 and 26 are adjacent (that is, the direction perpendicular to the axial direction of the pipe SP to be inspected and along the circumferential direction of the pipe SP to be inspected). Therefore, if the cross-section of the pipe SP to be inspected that is in contact with the pair of contact surfaces 25 and 26 is not a perfect circle, the orientation of the exploration unit 21a can be changed to a more appropriate direction.

[0063] Furthermore, in this embodiment, when the lever 48 rotates in response to the operation of the operating unit 56, the oscillating plate 49 moves in one direction in conjunction with this rotation. The probe 21, which receives the pressing force from the oscillating plate 49, changes the orientation of the exploration unit 21a using the pivot point 41 as the pivot point. At this time, the orientation of the exploration unit 21a of the probe 21 changes as the oscillating plate 49 moves in a direction in which the pair of contact surfaces 25 and 26 are adjacent to each other, so the direction of oscillation of the probe 21 becomes the direction in which the pair of contact surfaces 25 and 26 are adjacent. Therefore, if the cross-section of the inspection target pipe SP that contacts the pair of contact surfaces 25 and 26 is not a perfect circle, the orientation of the exploration unit 21a can be changed to a more appropriate direction. Moreover, the oscillating mechanism 40 can be constructed with a simple mechanism that converts rotational motion into linear motion.

[0064] Furthermore, in this embodiment, the inspection head 12 is configured to be rotatable relative to the elongated member 11 so that the connection angle with the elongated member 11 can be changed. Therefore, the connection angle of the inspection head 12 relative to the elongated member 11 can be changed according to the circumferential position of the pipe SP to be inspected. This makes it possible to inspect the pipe SP at various circumferential positions. Moreover, since the second spring member 16, which constitutes the biasing means 18 for stabilizing the inspection head 12 in a neutral position, is configured to connect the operating unit 56 and the swing mechanism 40, the swing operation of the inspection head 12 is performed using the second spring member 16. Consequently, an increase in the number of parts is suppressed.

[0065] Furthermore, in this embodiment, since a display unit 33a is provided, the user of the pipe inspection device 10 can operate the operation unit 56 while referring to the output corresponding to the reflected wave displayed on the display unit 33a. Therefore, it is possible to assist in orienteding the probe unit 21a of the probe 21 appropriately, thereby simplifying operation.

[0066] Furthermore, in this embodiment, since magnets 29 are provided on each of the pair of contact surfaces 25 and 26, the inspection target pipe SP that comes into contact with the contact surfaces 25 and 26 can be attracted by the magnets 29. Therefore, the inspection head 12 can be held in place so that it does not shift position relative to the inspection target pipe SP during inspection. Thus, stable inspection results can be obtained. Moreover, since the magnets 29 are formed in a flat shape and are arranged along the pair of contact surfaces 25 and 26, the inspection target pipe SP can be effectively attracted.

[0067] It should be noted that the embodiments disclosed herein are illustrative and not restrictive in all respects. The present invention is not limited to the embodiments described above, and various modifications and improvements are possible without departing from its spirit. For example, in the above embodiment, the rocking mechanism 40 is configured such that the rocking plate 49 moves in the front-rear direction by the rotation of the lever 48, but the invention is not limited to this configuration. The rocking mechanism 40 may be configured to include, for example, a solenoid or an air cylinder that moves the rocking plate 49 in the front-rear direction instead of the lever 48.

[0068] Furthermore, in the above embodiment, the inspection head 12 is configured to be rotatable relative to the elongated member 11. However, in cases where the inspection range is limited, such as when inspecting only the lower surface of the pipe SP to be inspected, the inspection head 12 may be fixed so as not to rotate relative to the elongated member 11. In this case, the first spring member 15 and the second spring member 16 are omitted, and the operating unit 56 is directly connected to the lever 48.

[0069] Furthermore, in the above embodiment, the operating unit 56 and the oscillating mechanism 40 are connected via a second spring member 16 for stabilizing the inspection head 12 in a neutral position, but the configuration is not limited to this. The operating unit 56 and the oscillating mechanism 40 may be directly connected, or a member other than the second spring member 16 may be interposed between the operating unit 56 and the oscillating mechanism 40.

[0070] Furthermore, although the magnet 29 is formed in a flat plate shape in the above embodiment, the magnet 29 does not have to be flat, and may be a roller-type magnet 29. It is also possible to omit the magnet 29.

[0071] Furthermore, although the above embodiment includes a rocking mechanism 40 and an operating unit 56, as shown in Figure 9, the rocking mechanism 40 and the operating unit 56 can be omitted. That is, if the probe 21 is supported on the head body 22 in a way that allows for variable relative orientation of the exploration unit 21a with respect to the head body 22, the probe 21 can be rocked by contact with the pipe SP to be inspected, even without the rocking mechanism 40 and the operating unit 56. This allows the exploration unit 21a to be aligned with the outer surface of the pipe SP to be inspected in a direction perpendicular to it. In this case, the probe 21 may be held in a rockable manner in the mounting hole 35 via a cylindrical member 43, similar to the probe 21 shown in Figure 5.

[0072] The probe portion 21a of the probe 21 is set to protrude beyond a virtual arc that contacts a pair of contact surfaces 25 and 26 that form a V-shaped groove. Therefore, the probe portion 21a can contact the inspection target pipe SP positioned by the contact surfaces 25 and 26.

[0073] The head body 22 is stabilized in a neutral position by a first spring member 15 and a second spring member 16. The first spring member 15 connects the rear end of the head body 22 to a second pin member 14d, which is stretched between elongated flat plates 14a. The second spring member 16 is located closer to the base side 13 than the first spring member 15. The second spring member 16 connects the rear end of the head body 22 to a third pin member 14e, which is stretched between elongated flat plates 14a. The third pin member 14e is held by the elongated flat plate 14a at a position closer to the base side 13 than the second pin member 14d.

[0074] The first spring member 15 biases the inspection head 12 in a first direction in the rotational direction (counterclockwise direction in Figure 9). The second spring member 16 biases the inspection head 12 in a second direction (clockwise direction in Figure 9), which is opposite to the first direction. As a result, when the inspection head 12 is subjected to an external force that causes it to rotate around the first pin member 14c (see Figure 1(b)) so that its front end (left end in Figure 9) rises, the first spring member 15 applies a tensile force to the inspection head 12 that causes it to rotate in a direction that causes its front end to descend. On the other hand, when the inspection head 12 is subjected to an external force that causes it to rotate around the first pin member 14c so that its front end descends, the second spring member 16 applies a tensile force to the inspection head 12 that causes it to rotate in a direction that causes its front end to rise. Therefore, the inspection head 12 can be rotated along the circumference of the pipe SP to be inspected, and the head body 22 can be naturally returned to the neutral position when the inspection head 12 moves away from the pipe SP to be inspected. In addition, when the inspection head 12 is rotated along the circumference of the pipe SP to be inspected, the orientation of the exploration unit 21a relative to the head body 22 can be changed so that the probe 21 follows the shape of the pipe SP to be inspected. [Explanation of Symbols]

[0075] 10: Pipe inspection equipment 11: Long member 12: Inspection head 15: First spring member 16: Second spring member 18: Biasing means 21: Probe 21a: Exploration Department 22: Head body 25: Contact surface 26: Contact surface 29: Magnet 33a: Display section 40: Oscillating mechanism 41: Pivot point 42: Pressing part 43: Cylindrical member 48: Lever 49: Oscillating plate 56:Operation section SP: Pipe to be inspected

Claims

1. A pipe inspection device used to inspect a pipe to be inspected in a group of pipes in which multiple pipes extending in a predetermined direction are arranged at intervals from one another, Long members and The long member comprises an inspection head positioned at its tip, The inspection head is A head body having a pair of contact surfaces that form a V-shaped groove, The probe has a probe at its tip for detecting the state of the pipe to be inspected, and is positioned between the pair of contact surfaces. The probe is a pipe inspection device in which the relative orientation of the probe to the head body is variably controlled by the head body.

2. Control panel and The pipe inspection device according to claim 1, further comprising a swinging mechanism that changes the relative orientation of the exploration section with respect to the head body by operation of the operating section.

3. The rocking mechanism includes a pivot point that defines the pivot point of the probe, and a pressing part configured to apply a pressing force to the probe at a position away from the pivot point and in a direction in which the pair of contact surfaces are adjacent to each other. The pipe inspection device according to claim 2, wherein the probe, upon receiving a pressing force from the pressing portion, changes the relative orientation of the exploration portion with respect to the head body, with the pivot portion acting as a pivot point.

4. The pipe inspection device according to claim 3, wherein the pressing portion includes a lever provided to rotate in response to the operation of the operating portion, and a rocking plate configured such that a pressing force is applied to the probe by the pair of contact surfaces moving in adjacent directions in conjunction with the rotation of the lever.

5. The inspection head is configured to be rotatable with respect to the elongated member so as to change the connection angle with respect to the elongated member. The pipe inspection device further includes a biasing means for stabilizing the inspection head in a neutral position where the connection angle of the inspection head to the elongated member is a predetermined angle. The pipe inspection device according to claim 2, wherein the biasing means comprises a first spring member that biases the inspection head in a first orientation in the rotational direction, and a second spring member that connects the operating unit and the oscillating mechanism and biases the inspection head in a second orientation opposite to the first orientation in the rotational direction.

6. The inspection head is configured to be rotatable with respect to the elongated member so as to change the connection angle with respect to the elongated member. The pipe inspection device further includes a biasing means for stabilizing the inspection head in a neutral position where the connection angle of the inspection head to the elongated member is a predetermined angle. The pipe inspection device according to claim 1, wherein the biasing means comprises a first spring member that biases the inspection head in a first orientation in the rotational direction, and a second spring member that biases the inspection head in a second orientation opposite to the first orientation in the rotational direction.

7. The pipe inspection device according to any one of claims 1 to 5, further comprising a display unit that displays an output corresponding to a signal received from the exploration unit.

8. The pipe inspection device according to any one of claims 1 to 5, wherein magnets are provided along the pair of contact surfaces.

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