Ultrasonic inspection device, ultrasonic inspection system, and ultrasonic inspection method

Abstract

To provide an ultrasonic inspection device suitable for inspecting a taper part of piping.SOLUTION: An ultrasonic inspection device according to an embodiment comprises a circular truncated cone-shaped base having an outer peripheral surface facing an inner peripheral surface of a taper part, and a plurality of ultrasonic vibrators, on the outer peripheral surface of the base, extending in a longer direction of the base and arranged in parallel with each other in a circumferential direction of the base.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an ultrasonic inspection device, an ultrasonic inspection system, and an ultrasonic inspection method. [Background technology]

[0002] As disclosed in Patent Documents 1 and 2, ultrasonic inspection devices are used for inspections such as measuring the wall thickness of pipes of boilers and detecting internal flaws. In Patent Document 1, the ultrasonic inspection device is inserted into the inside of the pipe, and ultrasonic waves are irradiated onto the pipe from the ultrasonic inspection device to inspect the pipe. As disclosed in Patent Document 1, the pipe also includes a tapered portion where the inner diameter gradually changes. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-004603 [Patent Document 2] Japanese Patent Application Laid-Open No. 2004-020333 Summary of the Invention [Problem to be solved by the invention]

[0004] The inventors have found various problems in developing an ultrasonic inspection device that is inserted into a pipe and that irradiates an ultrasonic wave onto a tapered portion of the pipe to inspect the tapered portion. Other objects and novel features will become apparent from the description of this specification and the accompanying drawings. [Means for solving the problem]

[0005] An ultrasonic inspection device according to one embodiment comprises a truncated cone-shaped base having an outer peripheral surface facing the inner peripheral surface of the tapered portion, and a plurality of ultrasonic transducers extending along the longitudinal direction of the base on the outer peripheral surface of the base and arranged side by side along the circumferential direction of the base. [Effects of the Invention]

[0006] According to the embodiment, it is possible to provide an ultrasonic inspection device suitable for inspecting tapered portions of piping. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a block diagram schematically illustrating an example of the configuration of an ultrasonic inspection system using an ultrasonic inspection device according to a first embodiment. [Figure 2] 1 is a side view schematically showing the configuration of an ultrasonic inspection device according to a first embodiment. [Figure 3] 1 is a schematic cross-sectional view of an ultrasonic inspection device 10 showing how an ultrasonic transducer 12 that transmits ultrasonic waves and receives reflected waves is switched. [Figure 4] FIG. 2 is a front view of the alignment mechanism 13a. [Figure 5] FIG. 10 is a side view of the alignment mechanism 13a. [Figure 6] 10 is a front view showing the operation of the alignment mechanism 13a when the inner diameter of the pipe changes. FIG. [Figure 7] 10 is a front view showing the operation of the alignment mechanism 13a when the inner diameter of the pipe changes. FIG. [Figure 8] 10 is a front view showing the operation of the alignment mechanism 13a when the inner diameter of the pipe changes. FIG. [Figure 9] FIG. 1 is a side view schematically showing an ultrasonic inspection device according to a first comparative example. [Figure 10] FIG. 1 is a side view schematically showing an ultrasonic inspection device according to a first comparative example. [Figure 11] FIG. 1 is a side view schematically showing an ultrasonic inspection device according to a first comparative example. [Figure 12] FIG. 10 is a side view schematically showing an ultrasonic inspection device according to Comparative Example 2. [Figure 13] 1 is a front view of a water tube boiler, which is an example of an object to be inspected by an ultrasonic inspection device according to a first embodiment. [Figure 14] FIG. 10 is a side view schematically showing an ultrasonic inspection device according to a second embodiment. [Figure 15]FIG. 10 is a side view schematically showing an ultrasonic inspection device according to a second embodiment. [Figure 16] FIG. 10 is a side view schematically showing an ultrasonic inspection device according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Specific embodiments will be described in detail below with reference to the drawings. However, the present invention is not limited to the following embodiments. In addition, the following description and drawings have been simplified appropriately for clarity.

[0009] (First embodiment) <Ultrasound inspection system configuration> First, an example of the configuration of an ultrasonic inspection system using the ultrasonic inspection device according to the first embodiment will be described with reference to Fig. 1. Fig. 1 is a block diagram schematically showing an example of the configuration of an ultrasonic inspection system using the ultrasonic inspection device according to the first embodiment. The ultrasonic inspection system shown in FIG. 1 includes an ultrasonic inspection device 10 according to this embodiment, as well as a multiplexer MUX, an ultrasonic pulser receiver UPR, a selection control unit SC, and a waveform display device OSC.

[0010] The ultrasonic inspection device 10 is inserted into a pipe and irradiates a tapered portion of the pipe with ultrasonic waves to inspect the tapered portion. Fig. 1 shows a schematic side view of the ultrasonic inspection device 10. As shown in Fig. 1, the ultrasonic inspection device 10 includes a base 11 and a plurality of ultrasonic transducers 12.

[0011] The base portion 11 is a truncated cone-shaped member having an outer peripheral surface facing the inner peripheral surface of the tapered portion. The ultrasonic vibrators 12 are provided on the outer peripheral surface of the base 11, extending along the longitudinal direction of the base 11, and are also provided side by side along the circumferential direction of the base 11. Each ultrasonic vibrator 12 corresponds to each channel of the multi-channel cable MCC. The ultrasonic inspection device 10 will be described in detail later.

[0012] The ultrasonic inspection device 10 is connected to the multiplexer MUX via a multi-channel cable MCC. The multi-channel cable MCC is a cable in which multiple wires connected to each ultrasonic transducer 12 are bundled together, and is, for example, a coaxial cable. In the example shown in FIG. 1, when the ultrasonic inspection device 10 moves inside the pipe, the multi-channel cable MCC is routed inside the pipe.

[0013] The multiplexer MUX is connected to the ultrasonic inspection device 10 via a multi-channel cable MCC, and is also connected to the ultrasonic pulser receiver UPR via a single-channel cable SCC. The multiplexer MUX is a selection circuit that selects one channel of the multi-channel cable MCC based on a selection control signal sel output from the selection control unit SC.

[0014] The multi-channel cable MCC is not essential, and each channel of the multiplexer MUX may be directly connected to each ultrasonic transducer 12 of the ultrasonic inspection device 10 without the multi-channel cable MCC. In this case, the multiplexer MUX moves within the piping together with the ultrasonic inspection device 10. A cable thinner than the multi-channel cable MCC can be used as the cable to be routed within the piping.

[0015] As shown in Fig. 1, an ultrasonic pulser receiver (ultrasonic transmitter / receiver) UPR transmits a transmission pulse (first pulse signal) tp and receives a reception pulse (second pulse signal) rp. The transmission pulse tp transmitted from the ultrasonic pulser receiver UPR reaches an ultrasonic transducer 12 of an ultrasonic inspection device 10 via a multiplexer MUX and a multi-channel cable MCC. That is, the transmission pulse tp reaches the ultrasonic transducer 12 selected by the multiplexer MUX, and the selected ultrasonic transducer 12 emits ultrasonic waves. The ultrasonic waves emitted from the ultrasonic transducer 12 are reflected by the inner and outer circumferential surfaces of the pipe.

[0016] Furthermore, the ultrasonic transducer 12 selected by the multiplexer MUX (i.e., the transducer that transmitted the ultrasonic wave) receives the ultrasonic wave reflected by the piping and transmits a received pulse rp, which is an electrical signal. The received pulse rp is received by the ultrasonic pulser receiver UPR via the multi-channel cable MCC, the multiplexer MUX, and the single-channel cable SCC.

[0017] The selection control unit SC outputs a selection control signal sel to the multiplexer MUX. As described above, the multiplexer MUX selects one channel of the multi-channel cable MCC based on the selection control signal sel output from the selection control unit SC. 1, the selection control unit SC generates the selection control signal sel based on, for example, a transmission pulse tp output from the ultrasonic pulser receiver UPR. Therefore, every time a transmission pulse tp is output from the ultrasonic pulser receiver UPR, the channel selected in the multi-channel cable MCC is switched, and the ultrasonic transducers 12 that transmit and receive ultrasonic waves are switched.

[0018] The waveform display device OSC receives the received pulses rp from the ultrasonic pulser receiver UPR and displays the waveforms of the received pulses rp. The waveform display device OSC is, for example, an oscilloscope. For example, the waveforms of the two received pulses rp based on the ultrasonic waves reflected by the inner and outer surfaces of the pipe being inspected are displayed on the waveform display device OSC. The wall thickness of the pipe can be measured from the waveforms of the two received pulses rp displayed on the waveform display device OSC. As a result, it is possible to detect thinning of the pipe due to, for example, corrosion or wear.

[0019] <Configuration of ultrasonic inspection equipment> Next, an example of the configuration of the ultrasonic inspection device according to the first embodiment will be described in detail with reference to Fig. 2. Fig. 2 is a side view schematically showing the configuration of the ultrasonic inspection device according to the first embodiment. The right-handed xyz Cartesian coordinate system shown in FIG. 2 and other drawings is for convenience in explaining the positional relationship of the components, and is common among the drawings.

[0020] As shown in Fig. 2, the ultrasonic inspection device 10 according to this embodiment includes a base 11, a plurality of ultrasonic transducers 12, and alignment mechanisms 13a and 13b. Fig. 2 shows a cross-sectional view of a pipe to be inspected. The pipe shown in Fig. 2 has a tapered portion connecting a small diameter portion and a large diameter portion. The ultrasonic inspection device 10 according to this embodiment is a device for inspecting the tapered portion of a pipe.

[0021] The base 11 is a truncated cone-shaped member having an outer peripheral surface facing the inner peripheral surface of the tapered portion of the pipe. Here, it is preferable that the inclination angle of the outer peripheral surface with respect to the central axis of the base 11 and the inclination angle of the inner peripheral surface with respect to the central axis of the tapered portion are approximately equal, but a certain degree of deviation is permissible. In addition, the outer peripheral surface of the truncated cone-shaped base 11 may be curved to some extent. For example, the outer peripheral surface of the base 11 may be curved so as to be concave inward. The base 11 is made of, for example, an insulating resin. The base 11 does not need to be solid as long as it can support the ultrasonic transducer 12, and may be hollow (including cylindrical).

[0022] The ultrasonic vibrators 12 are provided on the outer peripheral surface of the base 11, extending along the longitudinal direction of the base 11, and are also provided side by side along the circumferential direction of the base 11. Each ultrasonic vibrator 12 is connected to a wiring constituting the multi-channel cable MCC. That is, each ultrasonic vibrator 12 corresponds to a channel of the multi-channel cable MCC. For example, if there are 60 ultrasonic vibrators 12, a 60-channel multi-channel cable MCC is used. Naturally, the number of ultrasonic transducers 12, i.e., the number of channels, is determined appropriately. In addition, a sound absorbing material layer may be provided between the ultrasonic transducer 12 and the base 11 to reduce the pulse width of the ultrasonic waves.

[0023] As described above, the transmission pulse tp transmitted from the ultrasonic pulser receiver UPR shown in Fig. 1 reaches the ultrasonic transducer 12 selected by the multiplexer MUX via the multi-channel cable MCC. The ultrasonic transducer 12 transmits an ultrasonic wave UW based on the transmission pulse tp, which is an electrical signal. Furthermore, the ultrasonic transducer 12 receives the ultrasonic wave UW reflected by the piping and transmits a reception pulse rp, which is an electrical signal.

[0024] Here, Fig. 3 is a schematic cross-sectional view of the ultrasonic inspection device 10 showing how the ultrasonic transducers 12 that transmit and receive ultrasonic waves UW are switched. As shown in Fig. 3, each time the channel selected in the multi-channel cable MCC is switched, the ultrasonic transducers 12 that transmit and receive ultrasonic waves UW are switched sequentially along the circumferential direction of the base 11. As shown in Fig. 3, by having all the ultrasonic transducers 12 transmit and receive ultrasonic waves UW, the entire circumference of the pipe can be inspected. For example, inspection can be performed at a speed of about 200 revolutions per second.

[0025] Alignment mechanisms 13a and 13b are provided at both axial ends of base 11. Specifically, alignment mechanism 13a is provided at the end of base 11 on the positive x-axis side, and alignment mechanism 13b is provided at the end of base 11 on the negative x-axis side. Alignment mechanisms 13a and 13b can move along the axial direction of the tapered portion while supporting base 11 at the axial center of the tapered portion. That is, ultrasonic inspection device 10 inspects the entire tapered portion while supporting base 11 at the axial center of the tapered portion using alignment mechanisms 13a and 13b and moving along the axial direction of the tapered portion. That is, the central axis of base 11 and the central axis of the tapered portion are approximately aligned.

[0026] <Detailed configuration of the alignment mechanism> Here, the detailed configuration of one alignment mechanism 13a will be described with reference to Figures 4 and 5. Figure 4 is a front view of alignment mechanism 13a. Figure 5 is a side view of alignment mechanism 13a. The other alignment mechanism 13b has the same configuration as alignment mechanism 13a, so only alignment mechanism 13a will be described.

[0027] 4 and 5, the alignment mechanism 13a includes a cylindrical shaft 31, a disk member 32, a connecting link 33, an arm 34, a wheel 35, and a torsion spring SP. Here, as shown in Fig. 4, three connecting links 33, three arms 34, and three wheels 35 are provided. The torsion spring SP is shown only in Fig. 5. In Figs. 4 and 5, the cylindrical shaft 31 is shown by dots to facilitate understanding.

[0028] The cylindrical shaft 31 is a cylindrical shaft and constitutes the axis of the alignment mechanism 13a. The base 11 is rotatably fitted inside the cylindrical shaft 31. That is, the base 11 is rotatably supported by the cylindrical shaft 31 via, for example, a bearing or a bush (not shown). The cylindrical shaft 31 has protrusions 31a formed on its outer circumferential surface that protrude radially outward. As shown in FIG. 4, three protrusions 31a are provided at equal intervals along the circumferential direction of the cylindrical shaft 31.

[0029] It is not necessary for the cylindrical shaft 31 and the base 11 to be rotatable. For example, if the wheels 35 are wheels that can move in all directions, the cylindrical shaft 31 and the base 11 may be fixed to each other. Alternatively, if the entire wheel 35 or its surface is made of a material with low slip resistance (for example, fluororesin), the cylindrical shaft 31 and the base 11 may be fixed to each other.

[0030] The disk member 32 is an annular disk member having a through-hole in the center. The cylindrical shaft 31 is rotatably fitted into the through-hole of the disk member 32. In other words, as shown in FIG. 4, the cylindrical shaft 31 and the disk member 32 are arranged to be rotatable relative to each other, with the joint J1 formed by the cylindrical shaft 31 serving as the rotation axis. Also, as shown in FIG. 5, the front surface (the main surface on the x-axis negative direction side) of the disk member 32 abuts against the back surface (the surface on the x-axis positive direction side) of the protruding portion 31a of the cylindrical shaft 31.

[0031] 5, the cylindrical shaft 31 protruding from the back surface (the main surface on the x-axis positive side) of the disk member 32 is inserted into the torsion spring SP. In other words, the torsion spring SP is provided so as to cover the outer circumferential surface of the cylindrical shaft 31 protruding from the back surface of the disk member 32. One end (the end on the x-axis positive side) of the torsion spring SP is fixed to the outer circumferential surface of the cylindrical shaft 31, and the other end (the end on the x-axis negative side) of the torsion spring SP is fixed to the back surface of the disk member 32.

[0032] That is, the cylindrical shaft 31 and the disk member 32 are connected via the torsion spring SP. The torsion spring SP applies a rotational force that rotates the cylindrical shaft 31 and the disk member 32 relative to each other so that the tip end of an arm 34, which will be described in detail later, protrudes radially outward from the cylindrical shaft 31.

[0033] As shown in Fig. 4, the connecting link 33 is a link member that connects the disc member 32 and the arm 34. One end of the connecting link 33 is rotatably connected to the outer edge of the disc member 32, with a joint J2 formed, for example, by a pin, serving as a rotation axis. Three connecting links 33 and three joints J2 are provided at equal intervals along the circumferential direction of the disc member 32. Meanwhile, the other end of the connecting link 33 is rotatably connected to the middle of the arm 34, with a joint J3 formed, for example, by a pin, serving as a rotation axis. As shown in FIG. 5, the connecting link 33 is provided between the disk member 32 and the arm 34 in the x-axis direction, similar to the protruding portion 31a of the cylindrical shaft 31.

[0034] As shown in Fig. 4, the arm 34 is an arc-shaped link member. The base of the arm 34 is rotatably connected to the protruding portion 31a of the cylindrical shaft 31, with a joint J4, which is formed, for example, by a pin, as the rotation axis. In addition, a wheel 35 that abuts against the inner peripheral surface of the pipe is provided at the tip of the arm 34. The wheel 35 allows the ultrasonic inspection device 10 to easily move in the axial direction of the pipe. As shown in FIG. 5, the arm 34 is disposed opposite the disk member 32 in the x-axis direction, with the connecting link 33 and the protruding portion 31a of the cylindrical shaft 31 interposed therebetween.

[0035] 4, the protrusion 31a of the cylindrical shaft 31, the disk member 32, the connecting link 33, and the arm 34 correspond to links that make up a four-bar link. This four-bar link is a pantograph-type link mechanism in which the joint J1 between the cylindrical shaft 31 and the disk member 32 is a fixed end. The number of arms 34 is not limited to three, but may be any number.

[0036] <Operation of the alignment mechanism> Here, with reference to Figs. 6 to 8, the operation of alignment mechanism 13a when the inner diameter of the pipe changes will be described. Figs. 6 to 8 are front views showing the operation of alignment mechanism 13a when the inner diameter of the pipe changes. Specifically, Fig. 6 shows the state of alignment mechanism 13a in the small diameter portion. Fig. 7 shows the state of alignment mechanism 13a in the tapered portion. Fig. 8 shows the state of alignment mechanism 13a in the large diameter portion. In the tapered portion, the state of alignment mechanism 13a gradually changes from the state of alignment mechanism 13a in the small diameter portion shown in Fig. 6 to the state of alignment mechanism 13a in the large diameter portion shown in Fig. 8. The operation of the other alignment mechanism 13b is the same as that of alignment mechanism 13a.

[0037] 6 to 8, consider the case where the alignment mechanism 13a moves from the small diameter portion via the tapered portion to the large diameter portion. In this case, the disk member 32 and the cylindrical shaft 31 rotate relative to each other so that the joint J2 fixed to the disk member 32 and the joint J4 fixed to the protruding portion 31a of the cylindrical shaft 31 move closer to each other. As a result, the joint J3 moves radially outward of the cylindrical shaft 31, and the tip of the arm 34 (i.e., the wheel 35) moves away from the cylindrical shaft 31. In FIG. 8, the joint J2 and the joint J4 are closest to each other, and the tip of the arm 34 (i.e., the wheel 35) is farthest from the cylindrical shaft 31.

[0038] Consider a case where the alignment mechanism 13a moves from the large diameter portion via the tapered portion to the small diameter portion in the reverse order of Figures 6 to 8. In this case, the disk member 32 and the cylindrical shaft 31 rotate relative to each other so that the joint J2 fixed to the disk member 32 and the joint J4 fixed to the protruding portion 31a of the cylindrical shaft 31 move away from each other. As a result, the joint J3 moves radially inward of the cylindrical shaft 31, and the tip of the arm 34 (i.e., the wheel 35) moves closer to the cylindrical shaft 31. In Figure 6, the joint J2 and the joint J4 are furthest apart, and the tip of the arm 34 (i.e., the wheel 35) is closest to the cylindrical shaft 31.

[0039] As described above, the torsion spring SP applies a rotational force that rotates the cylindrical shaft 31 and the disk member 32 relative to each other so that the wheel 35 is always in contact with the inner peripheral surface of the pipe. That is, as shown in Figures 6 to 8, the wheel 35 is always pressed against the inner peripheral surface of the pipe, and the position of the wheel 35 in the circumferential direction of the pipe does not change much. Therefore, in the operations shown in Figures 6 to 8, the disk member 32 and the cylindrical shaft 31 rotate so that the joints J2 and J4 move closer to or farther away from each other.

[0040] <Configuration of Ultrasonic Inspection Device According to Comparative Example 1> Next, an ultrasonic inspection device according to Comparative Example 1, which was previously investigated by the inventors, will be described with reference to Figures 9 to 11. Figures 9 to 11 are side views that schematically show the ultrasonic inspection device according to Comparative Example 1. Figures 9 to 11 correspond to Figure 2. The ultrasonic inspection system using the ultrasonic inspection device 100 according to Comparative Example 1 has the same configuration as that shown in FIG.

[0041] As shown in FIGS. 9 to 11, the ultrasonic inspection device 100 according to Comparative Example 1 includes a base 110, multiple ultrasonic transducers 120, and alignment mechanisms 130a and 130b. Here, FIGS. 9 to 11 show cross-sectional views of the pipe to be inspected. The pipe shown in FIGS. 9 to 11 has a tapered portion connecting a small diameter portion and a large diameter portion. The ultrasonic inspection device 100 according to Comparative Example 1 is an apparatus for inspecting the small diameter portion and the large diameter portion, i.e., the constant diameter portion, of a pipe with a constant inner diameter. As will be described later, the ultrasonic inspection device 100 according to Comparative Example 1 cannot inspect the tapered portion of the pipe.

[0042] In the ultrasonic inspection device 10 according to this embodiment shown in Fig. 2, the base 11 is a truncated cone-shaped member having an outer circumferential surface facing the inner circumferential surface of the tapered portion. In contrast, in the ultrasonic inspection device 100 according to Comparative Example 1 shown in Figs. 9 to 11, the base 110 is a cylindrical member having an outer circumferential surface facing the inner circumferential surfaces of the small diameter portion and the large diameter portion. The base 110 is made of, for example, an insulating resin, similar to the base 11. The base 110 does not need to be solid as long as it can support the ultrasonic transducer 120, and may be hollow (including cylindrical).

[0043] The ultrasonic transducers 120 are provided on the outer peripheral surface of the base 110, extending along the longitudinal direction of the base 110, and are also provided side by side along the circumferential direction of the base 110. Each ultrasonic transducer 120 is connected to wiring that constitutes the multi-channel cable MCC. That is, the ultrasonic transducer 120 of the ultrasonic inspection device 100 according to Comparative Example 1 has the same configuration as the ultrasonic transducer 12 of the ultrasonic inspection device 10 according to this embodiment. Moreover, the alignment mechanisms 130a and 130b of the ultrasonic inspection device 100 according to Comparative Example 1 have the same configuration as the alignment mechanisms 13a and 13b of the ultrasonic inspection device 10 according to this embodiment.

[0044] 9 and 11, the outer peripheral surface of the base 110 on which the ultrasonic vibrator 120 is formed faces the inner peripheral surface of the pipe in the small diameter and large diameter sections of the pipe. Therefore, when the ultrasonic vibrator 120 selected by the multiplexer MUX shown in Fig. 1 transmits an ultrasonic wave UW, it can receive the ultrasonic wave UW reflected by the small diameter and large diameter sections of the pipe, as shown in Fig. 9 and 11.

[0045] On the other hand, as shown in Fig. 10, in the tapered portion of the pipe, the outer peripheral surface of the base 110 on which the ultrasonic vibrator 120 is formed does not face the inner peripheral surface of the pipe. Therefore, even if the ultrasonic vibrator 120 selected by the multiplexer MUX shown in Fig. 1 transmits an ultrasonic wave UW, it cannot receive the ultrasonic wave UW reflected by the tapered portion of the pipe, as shown in Fig. 10. Therefore, the ultrasonic inspection device 100 according to Comparative Example 1 cannot inspect the tapered portion of the pipe, and it is necessary to use another ultrasonic inspection device for the tapered portion of the pipe.

[0046] <Configuration of Ultrasonic Inspection Device According to Comparative Example 2> Next, an ultrasonic inspection device according to Comparative Example 2, which was previously investigated by the inventor, will be described with reference to Fig. 12. Fig. 12 is a side view schematically showing the ultrasonic inspection device according to Comparative Example 2. Fig. 12 corresponds to Fig. 2.

[0047] As shown in Fig. 12, the ultrasonic inspection device 200 according to Comparative Example 2 includes a rotating shaft 14, a probe arm 15, an ultrasonic probe 16, and alignment mechanisms 130a and 130b. Fig. 12 shows a cross-sectional view of a pipe to be inspected. The pipe shown in Fig. 12 has a tapered portion connecting a small diameter portion and a large diameter portion. The ultrasonic inspection device 200 according to Comparative Example 2 is a device for inspecting the tapered portion of a pipe.

[0048] 12, a rotating shaft 14 extending in the axial direction of a pipe is supported at the axial center of the tapered portion by alignment mechanisms 130a and 130b. The rotating shaft 14 is rotatably supported by the alignment mechanisms 130a and 130b, and is rotationally driven by a drive source such as a motor (not shown). The alignment mechanisms 130a and 130b of the ultrasonic inspection device 200 according to Comparative Example 2 also have the same configuration as the alignment mechanisms 13a and 13b of the ultrasonic inspection device 10 according to this embodiment.

[0049] The base of the probe arm 15 is rotatably connected to the rotary shaft 14. On the other hand, an ultrasonic probe 16 is rotatably connected to the tip of the probe arm 15. When the rotary shaft 14 is driven to rotate, the ultrasonic probe 16 is mechanically rotated in the circumferential direction of the tapered portion while being in contact with the tapered portion.

[0050] In this way, in the ultrasonic inspection device 200 according to Comparative Example 2, the ultrasonic probe 16 inspects the tapered portion by mechanically rotating in the circumferential direction of the tapered portion while being in contact with the tapered portion. Therefore, the ultrasonic inspection device 200 according to Comparative Example 2 has a problem in that the inspection speed is slow.

[0051] The ultrasonic probe 16 is connected to the ultrasonic pulser receiver UPR shown in Fig. 1 via a single channel cable SCC. Therefore, in the ultrasonic inspection system using the ultrasonic inspection device 200 according to Comparative Example 2, the multi-channel cable MCC, multiplexer MUX, and selection control unit SC shown in Fig. 1 are not necessary.

[0052] <Explanation of effect> The effects achieved by the ultrasonic inspection device 10 according to this embodiment will be described below. As described above, in the ultrasonic inspection device 100 according to Comparative Example 1, the base 110 on which the ultrasonic transducer 120 is formed is cylindrical, and the outer peripheral surface of the base 110 does not face the inner peripheral surface of the tapered portion of the pipe. Therefore, even if the ultrasonic transducer 120 selected by the multiplexer MUX shown in Fig. 1 transmits an ultrasonic wave UW, it cannot receive the ultrasonic wave UW reflected by the tapered portion of the pipe, as shown in Fig. 10. Therefore, the ultrasonic inspection device 100 according to Comparative Example 1 cannot inspect the tapered portion of the pipe.

[0053] In contrast, as shown in Fig. 2, in the ultrasonic inspection device 10 according to this embodiment, the base 11 on which the ultrasonic transducers 12 are formed is frustum-shaped, and the outer circumferential surface of the base 11 is held so as to face the inner circumferential surface of the tapered portion of the pipe. Therefore, when the ultrasonic transducer 12 selected by the multiplexer MUX shown in Fig. 1 transmits an ultrasonic wave UW, it can receive the ultrasonic wave UW reflected by the tapered portion of the pipe, as shown in Fig. 2. In other words, the ultrasonic inspection device 10 according to this embodiment can inspect the tapered portion of the pipe.

[0054] Furthermore, in the ultrasonic inspection device 200 according to Comparative Example 2, the ultrasonic probe 16 inspects the tapered portion by mechanically rotating in the circumferential direction of the tapered portion while being in contact with the tapered portion, which poses a problem of slow inspection speed.

[0055] In contrast to this, in the ultrasonic inspection device 10 according to this embodiment, as shown in Fig. 3, the ultrasonic transducers 12 are arranged side by side on the outer peripheral surface of the base 11 along the circumferential direction of the base 11. Here, as shown in Fig. 3, every time the channel selected in the multi-channel cable MCC is electrically switched, the ultrasonic transducers 12 that transmit and receive ultrasonic waves UW are switched sequentially along the circumferential direction of the base 11. Then, by having all the ultrasonic transducers 12 transmit and receive ultrasonic waves UW, the entire circumference of the piping can be inspected.

[0056] With this configuration, the ultrasonic inspection device 10 according to this embodiment has an inspection speed that is about 10 times faster in the case of, for example, 60 channels, than the ultrasonic inspection device 200 according to Comparative Example 2, which mechanically rotates the ultrasonic probe 16. Note that since the number of channels corresponds to the number of data points in the circumferential direction of the pipe, the greater the number of channels, the more precise the inspection can be, but the slower the inspection speed. In this way, the ultrasonic inspection device 10 according to this embodiment can inspect the tapered portion of the pipe at high speed.

[0057] <Specific examples of inspection targets> Next, the configuration of a water tube boiler, which is an example of an object to be inspected by the ultrasonic inspection device according to this embodiment, will be described with reference to Fig. 13. Fig. 13 is a front view of a water tube boiler, which is an example of an object to be inspected by the ultrasonic inspection device according to the first embodiment.

[0058] The water tube boiler shown in Figure 13 is a double-drum curved pipe type water tube boiler. Here, the "double-drum" in "double-drum curved pipe type" refers to the two drums, the water drum and the steam drum, shown in Figure 13. Also, the "curved pipe" in "double-drum curved pipe type" means that the water tubes connecting the water drum and the steam drum are curved pipes rather than straight pipes.

[0059] The water drum provided at the bottom and the steam drum provided at the top both extend in the depth direction of the page. As shown in Fig. 13, a plurality of water pipes connecting the water drum and the steam drum are provided so as to extend linearly and substantially parallel to the vertical direction. Here, at the connection portions between each water pipe and the water drum and the steam drum, each water pipe is connected substantially perpendicular to the wall surfaces of the water drum and the steam drum. In other words, the plurality of water pipes are connected radially and aligned in the circumferential direction of the water drum and the steam drum.

[0060] In this way, the water pipes connecting the water drum and the steam drum mostly extend linearly and substantially parallel to the vertical direction, and are curved at both ends so as to connect substantially perpendicularly to the wall surfaces of the water drum and the steam drum. The water pipes connecting the water drum and the steam drum are also arranged in parallel in the longitudinal direction of the water drum and the steam drum (the depth direction of the paper in FIG. 13). Furthermore, as shown in FIG. 13, the furnace wall water pipe, which is curved largely in a C-shape and connects the water drum and the steam drum, is provided along the furnace wall of the combustion chamber.

[0061] 13, the water pipes and furnace wall water pipes have tapered portions near the connections with the water drum and steam drum. The ultrasonic inspection device 10 according to this embodiment can be used to inspect the tapered portions. The object to be inspected by the ultrasonic inspection device 10 according to this embodiment is not limited in any way as long as it is a pipe having a tapered portion.

[0062] (Second embodiment) Next, an ultrasonic inspection device according to a second embodiment will be described with reference to Figures 14 to 16. Figures 14 to 16 are side views schematically showing the ultrasonic inspection device according to the second embodiment. Figures 14 to 16 correspond to Figures 2 and 9 to 11.

[0063] 14 to 16, the ultrasonic inspection device 10 according to this embodiment includes a base 110 and a plurality of ultrasonic transducers 120 shown in FIGS. 9 to 11, in addition to the base 11, the plurality of ultrasonic transducers 12, and the alignment mechanisms 13a and 13b shown in FIG. 2. That is, the ultrasonic inspection device 10 according to this embodiment has both the configuration and functions of the ultrasonic inspection device 10 according to the first embodiment shown in FIG. 2 and the ultrasonic inspection device 100 according to Comparative Example 1 shown in FIGS. 9 to 11. Therefore, the ultrasonic inspection device 10 according to this embodiment can inspect small-diameter and large-diameter portions of piping in addition to tapered portions of piping.

[0064] 14 to 16, base (first base) 11 is a truncated cone-shaped member having an outer circumferential surface facing the inner circumferential surface of the tapered portion of the piping. Base 110 (second base) is a cylindrical member having an outer circumferential surface facing the inner circumferential surfaces of the small diameter portion and the large diameter portion of the piping. One end of base 11 is connected to one end of base 110.

[0065] In the example shown in FIGS. 14 to 16, one end of base 110 is connected to one end of base 11 on the small diameter side, and the diameter of the one end of base 11 on the small diameter side and the diameter of base 110 are equal. The base 11 and the base 110 may be integrally formed. Alternatively, one end of the base 110 may be connected to one end of the base 11 on the large diameter side.

[0066] The ultrasonic vibrators (first ultrasonic vibrators) 12 are provided on the outer peripheral surface of the base 11, extending along the longitudinal direction of the base 11, and are arranged side by side along the circumferential direction of the base 11. The ultrasonic vibrators (second ultrasonic vibrators) 120 are provided on the outer peripheral surface of the base 110, extending along the longitudinal direction of the base 110, and are arranged side by side along the circumferential direction of the base 110. For example, the number of ultrasonic vibrators 12 and the number of ultrasonic vibrators 120 are the same, and the ultrasonic vibrators 120 are provided on the extension of the ultrasonic vibrators 12.

[0067] Each ultrasonic transducer 12, 120 is connected to a wiring constituting the multi-channel cable MCC. That is, each ultrasonic transducer 12, 120 corresponds to a channel of the multi-channel cable MCC. For example, if there are 60 ultrasonic transducers 12, 120, a 120-channel multi-channel cable MCC is used.

[0068] Here, if 60 ultrasonic transducers 12 and 60 ultrasonic transducers 120 are connected in parallel to the multi-channel cable MCC, a 60-channel multi-channel cable MCC can be used, and the diameter of the multi-channel cable MCC can be reduced. Naturally, the number of ultrasonic transducers 12, 120, that is, the number of channels, is determined appropriately.

[0069] 14 and 16, in the small diameter portion and large diameter portion of the pipe, the outer peripheral surface of the base 110 on which the ultrasonic vibrator 120 is formed is held so as to face the inner peripheral surface of the pipe. Therefore, when the ultrasonic vibrator 120 selected by the multiplexer MUX shown in Fig. 1 transmits an ultrasonic wave UW, it can receive the ultrasonic wave UW reflected by the small diameter portion and large diameter portion of the pipe, as shown in Fig. 14 and 16.

[0070] On the other hand, as shown in Fig. 15, in the tapered portion of the pipe, the outer peripheral surface of the base 11 on which the ultrasonic vibrators 12 are formed is held so as to face the inner peripheral surface of the pipe. Therefore, when the ultrasonic vibrator 12 selected by the multiplexer MUX shown in Fig. 1 transmits an ultrasonic wave UW, it can receive the ultrasonic wave UW reflected by the tapered portion of the pipe, as shown in Fig. 15. Other configurations of the ultrasonic inspection device 10 according to the second embodiment are the same as those of the ultrasonic inspection device 10 according to the first embodiment, and therefore description thereof will be omitted.

[0071] The ultrasonic inspection device 10 according to the first embodiment can inspect tapered portions of pipes, but cannot inspect constant diameter portions of pipes. Therefore, to inspect constant diameter portions, it is necessary to separately use, for example, the ultrasonic inspection device 100 according to Comparative Example 1. In contrast, the ultrasonic inspection device 10 according to this embodiment can inspect not only tapered portions of a pipe but also small-diameter and large-diameter portions, i.e., constant-diameter portions of a pipe. In other words, the ultrasonic inspection device 10 according to this embodiment can inspect pipes more efficiently than the ultrasonic inspection device 10 according to the first embodiment.

[0072] The invention made by the inventor has been specifically described above based on the embodiments, but it goes without saying that the present invention is not limited to the embodiments already described, and various modifications are possible within the scope of the gist of the invention. [Explanation of symbols]

[0073] 10 Ultrasonic inspection equipment 11 Base (1st base) 110 Base (2nd base) 12 Ultrasonic vibrator (first ultrasonic vibrator) 120 ultrasonic vibrator (second ultrasonic vibrator) 13a, 13b Alignment mechanism 14 Rotating shaft 15 Probe arm 16 Ultrasonic probe 31 Cylindrical shaft 31a Protrusion 32 Disc member 33 Connecting Links 34 Arm 35 wheels J1~J4 joints MCC Multi-Channel Cable MUX Multiplexer OSC waveform display device SC selection control unit SCC Single Channel Cable SP torsion spring UPR Ultrasonic Pulser Receiver

Claims

1. An ultrasonic inspection device that is inserted into a pipe having a tapered portion whose inner diameter gradually changes, and that inspects the tapered portion by irradiating the tapered portion with ultrasonic waves, a truncated cone-shaped base portion having an outer peripheral surface facing parallel to the inner peripheral surface of the tapered portion within the tapered portion; a plurality of ultrasonic transducers that are provided on the outer peripheral surface of the base portion, extending along the longitudinal direction of the base portion and arranged side by side along the circumferential direction of the base portion; an alignment mechanism that supports the base portion at the axial center of the tapered portion and is movable along the axial direction of the tapered portion, When inspecting the tapered portion, ultrasonic waves are irradiated perpendicularly onto the inner circumferential surface of the tapered portion from each of the plurality of ultrasonic transducers while moving along the longitudinal direction of the tapered portion. Ultrasound testing equipment.

2. The piping has a constant diameter portion with a constant inner diameter, the base is a first base, and the plurality of ultrasonic transducers are a plurality of first ultrasonic transducers, a cylindrical second base portion connected to one end of the first base portion; a plurality of second ultrasonic transducers that are provided on the outer peripheral surface of the second base portion, extending along the longitudinal direction of the second base portion, and arranged side by side along the circumferential direction of the second base portion; When inspecting the constant diameter portion, ultrasonic waves are irradiated perpendicularly onto an inner peripheral surface of the constant diameter portion from each of the plurality of second ultrasonic transducers while moving along a longitudinal direction of the constant diameter portion. The ultrasonic inspection device according to claim 1 .

3. The alignment mechanism includes: A shaft, a plurality of arms provided at equal intervals along the circumferential direction of the shaft; One end of each of the plurality of arms is connected to an outer circumferential surface of the shaft so as to be rotatable in a circumferential direction of the shaft, The other end of each of the plurality of arms is biased so as to abut against the inner circumferential surface of the tapered portion. The ultrasonic inspection device according to claim 1 .

4. a wheel is provided on the other end of each of the arms that contacts the inner circumferential surface of the tapered portion; The ultrasonic inspection device according to claim 3 .

5. an ultrasonic inspection device that is inserted into a pipe having a tapered portion whose inner diameter gradually changes and that irradiates the tapered portion with ultrasonic waves to inspect the tapered portion; a selection circuit connected to the ultrasonic inspection device; a pulser receiver that transmits a first pulse signal for generating an ultrasonic wave to the ultrasonic inspection device via the selection circuit and receives a second pulse signal transmitted by the ultrasonic inspection device that has received the ultrasonic wave reflected by the tapered portion, The ultrasonic inspection device includes: a truncated cone-shaped base portion having an outer peripheral surface facing parallel to the inner peripheral surface of the tapered portion within the tapered portion; a plurality of ultrasonic transducers that are provided on the outer peripheral surface of the base portion, extending along the longitudinal direction of the base portion and arranged side by side along the circumferential direction of the base portion; an alignment mechanism that supports the base portion at the axial center of the tapered portion and is movable along the axial direction of the tapered portion, Each of the plurality of ultrasonic transducers is connected to a respective channel of the selection circuit, When inspecting the tapered portion, the ultrasonic inspection device moves along the longitudinal direction of the tapered portion, and sequentially irradiates ultrasonic waves perpendicularly onto the inner circumferential surface of the tapered portion from each of the plurality of ultrasonic transducers selected by the selection circuit. Ultrasound inspection system.

6. The piping has a constant diameter portion with a constant inner diameter, the base is a first base, and the plurality of ultrasonic transducers are a plurality of first ultrasonic transducers, The ultrasonic inspection device includes: a cylindrical second base portion connected to one end of the first base portion; a plurality of second ultrasonic transducers that are provided on the outer peripheral surface of the second base portion, extending along the longitudinal direction of the second base portion, and arranged side by side along the circumferential direction of the second base portion; each of the first ultrasonic transducers and the second ultrasonic transducers is connected to a corresponding channel of the selection circuit; When inspecting the constant diameter portion, the ultrasonic inspection device moves along the longitudinal direction of the constant diameter portion, and ultrasonic waves are sequentially irradiated perpendicularly onto the constant diameter portion from each of the plurality of second ultrasonic transducers selected by the selection circuit. The ultrasound inspection system of claim 5 .

7. The piping has a constant diameter portion with a constant inner diameter, the base is a first base, and the plurality of ultrasonic transducers are a plurality of first ultrasonic transducers, The ultrasonic inspection device includes: a cylindrical second base portion connected to one end of the first base portion; a plurality of second ultrasonic transducers that are provided on the outer peripheral surface of the second base portion, extending along the longitudinal direction of the second base portion, and arranged side by side along the circumferential direction of the second base portion; Each of the plurality of first ultrasonic transducers and each of the plurality of second ultrasonic transducers are connected in parallel to each channel of the selection circuit, When inspecting the constant diameter portion, the ultrasonic inspection device moves along the longitudinal direction of the constant diameter portion, and ultrasonic waves are sequentially irradiated perpendicularly onto the constant diameter portion from each of the plurality of second ultrasonic transducers selected by the selection circuit. The ultrasound inspection system of claim 5 .

8. The alignment mechanism includes: A shaft, a plurality of arms provided at equal intervals along the circumferential direction of the shaft; One end of each of the plurality of arms is connected to an outer circumferential surface of the shaft so as to be rotatable in a circumferential direction of the shaft, The other end of each of the plurality of arms is biased so as to abut against the inner circumferential surface of the tapered portion. The ultrasound inspection system of claim 5 .

9. a wheel is provided on the other end of each of the arms that contacts the inner circumferential surface of the tapered portion; The ultrasound inspection system of claim 8 .

10. (a) inserting an ultrasonic inspection device into a pipe having a tapered portion whose inner diameter gradually changes; (b) a step of irradiating the tapered portion with ultrasonic waves from the ultrasonic inspection device to inspect the tapered portion, The ultrasonic inspection device includes: a truncated cone-shaped base portion having an outer peripheral surface facing parallel to the inner peripheral surface of the tapered portion within the tapered portion; a plurality of ultrasonic transducers that are provided on the outer peripheral surface of the base portion, extending along the longitudinal direction of the base portion and arranged side by side along the circumferential direction of the base portion; an alignment mechanism that supports the base portion at the axial center of the tapered portion and is movable along the axial direction of the tapered portion, In step (b), The ultrasonic inspection device moves along the longitudinal direction of the tapered portion, and ultrasonic waves are sequentially irradiated perpendicularly to the tapered portion from each of the plurality of ultrasonic transducers. Ultrasound testing methods.

11. (c) further comprising a step of irradiating an ultrasonic wave from the ultrasonic inspection device to a constant diameter portion of the piping, the constant diameter portion having a constant inner diameter, to inspect the constant diameter portion; In the ultrasonic inspection device, the base is a first base, and the plurality of ultrasonic transducers are a plurality of first ultrasonic transducers, The ultrasonic inspection device includes: a cylindrical second base portion connected to one end of the first base portion; a plurality of second ultrasonic transducers that are provided on the outer peripheral surface of the second base portion, extending along the longitudinal direction of the second base portion, and that are arranged side by side along the circumferential direction of the second base portion; In step (c), The ultrasonic inspection device moves along the longitudinal direction of the constant diameter portion, and ultrasonic waves are sequentially irradiated perpendicularly to the constant diameter portion from each of the plurality of second ultrasonic transducers. The ultrasonic inspection method according to claim 10.

12. The alignment mechanism includes: A shaft, a plurality of arms provided at equal intervals along the circumferential direction of the shaft; One end of each of the plurality of arms is connected to an outer circumferential surface of the shaft so as to be rotatable in a circumferential direction of the shaft, The other end of each of the plurality of arms is biased so as to abut against the inner circumferential surface of the tapered portion. The ultrasonic inspection method according to claim 10.

13. a wheel is provided on the other end of each of the arms that contacts the inner circumferential surface of the tapered portion; The ultrasonic inspection method according to claim 12.

Images