Piping inspection device, piping inspection method, and piping inspection program

Abstract

This piping inspection device comprises a processor. The processor acquires first transmission information in which piping is transmission-imaged in a first imaging direction in which two side surfaces facing each other are included in a transmission path, and second transmission information in which the piping is transmission-imaged in a second imaging direction facing the first imaging direction, and outputs information based on a difference between the first transmission information and the second transmission information.　

Description

Piping inspection device, piping inspection method, and piping inspection program

[0001] The technology disclosed herein relates to a piping inspection device, a piping inspection method, and a piping inspection program.

[0002] The following techniques are known for non-destructive testing of piping. For example, Patent Document 1 (JP 4-343007 A) describes a method of measuring the transmittance distribution while moving a radiation source and a radiation measuring device arranged across the pipe in a direction perpendicular to the pipe axis, measuring the transmittance distribution while moving the radiation source and the radiation measuring device in a direction perpendicular to the direction of movement during measurement, comparing the measured transmittance distribution for each of the perpendicular directions with the expected transmittance, and calculating the blockage rate distribution for each of the perpendicular directions.

[0003] Patent Document 2 (Japanese Patent Laid-Open Publication No. 4-9606) describes a method of taking a radiographic photograph of a pipe by transmitting radiation from at least two directions that intersect with the pipe to be measured, importing the photograph into an image input device to detect the gradation value of the density at each point, and comparing the gradation value with a reference value to detect corroded areas.

[0004] Patent Document 3 (JP Patent Publication No. 11-118735) describes a method in which an X-ray generator and an X-ray detector are placed opposite each other on either side of the pipe to be inspected, X-rays are irradiated from the X-ray generator onto the pipe, and X-ray transmission information relating to pipe thinning, which is obtained from the transmitted X-rays and has gray values ​​for each unit pixel, is input and image analysis is performed to evaluate the state of thinning in the thinned part of the pipe.

[0005] Patent Document 4 (JP 2014-41057 A) describes a method in which a radiation source and at least two or more radiation detectors that simultaneously receive radiation from the radiation source that passes through the insulated pipe are arranged apart from each other in a direction intersecting the insulated pipe, sandwiching the insulated pipe; the radiation source and the radiation detector are moved along the central axis of the insulated pipe; and the thinning thickness of the pipe material is measured from the change in the amount of transmitted radiation that passes through the cross section of the insulated pipe and enters the radiation detector.

[0006] However, as in Patent Documents 1 to 4, when a radiation source and a panel (detector) are disposed opposite each other with the pipe in between to perform transmission imaging of the pipe, two opposing sides of the pipe, i.e., the side on the near side and the side on the far side as viewed from the radiation source, are included in the transmission path. Therefore, the results of transmission imaging in this manner contain a mixture of information from the two sides. As a result, information from one side may be obscured by information from the other side, making it difficult to inspect the pipe.

[0007] Therefore, the technology disclosed herein aims to provide an apparatus, method, and program that can facilitate piping inspection even when the photographed results contain a mixture of information from two different aspects.

[0008] In order to achieve the above object, the piping inspection device according to the disclosed technology includes a processor, which acquires first transmission information obtained by transmitting an image of the piping from a first shooting direction in which two opposing sides of the piping are included in the transmission path, and second transmission information obtained by transmitting an image of the piping from a second shooting direction opposite the first shooting direction, and outputs information based on the difference between the first transmission information and the second transmission information.

[0009] The processor may calculate a statistical value of the difference. The processor may determine whether or not there is a possibility of an abnormality in the pipe based on the magnitude of the statistical value. The processor may determine whether or not there is a possibility of an abnormality in the pipe based on a result of comparing the magnitude of the statistical value with a predetermined threshold. The processor may determine whether or not there is a possibility of an abnormality in the pipe based on an outlier in the magnitude of the statistical value. The processor may determine which side of the pipe may have a possible abnormality based on the positive or negative of the statistical value. The processor may acquire multiple sets of first transmission information and second transmission information when the pipe is subjected to transmission imaging under different imaging conditions, and output information based on the difference for each imaging condition. The imaging condition may be an imaging position on the pipe, and the processor may output information based on the difference for each imaging position. The imaging position may be a circumferential position on the pipe, and the processor may output information based on the difference for each circumferential position. The imaging position may be an axial position on the pipe, and the processor may output information based on the difference for each axial position. The processor may generate an imaging plan for performing transmission imaging of the pipe at different imaging positions, and acquire multiple sets of first transmission information and second transmission information when the pipe is subjected to transmission imaging in accordance with the imaging plan. The imaging plan may be a plan for performing transmission imaging of the pipe at different imaging positions while moving independently in the circumferential direction and the axial direction along the pipe. The imaging plan may be a plan for performing transmission imaging of the pipe at different imaging positions while moving spirally along the pipe. The processor may output information based on the difference in association with the imaging plan. The imaging condition may be the imaging time when the pipe is subjected to transmission imaging, and the processor may output information based on the difference for each imaging time. The two opposing side surfaces may be side surfaces at different positions in the circumferential direction of the pipe.

[0010] A piping inspection method according to the disclosed technology includes a computer acquiring first transmission information obtained by transmitting an image of a piping from a first shooting direction in which two opposing sides of the piping are included in the transmission path, and second transmission information obtained by transmitting an image of the piping from a second shooting direction opposite the first shooting direction, and outputting information based on the difference between the first transmission information and the second transmission information.

[0011] The piping inspection program relating to the technology of the present disclosure causes a computer to acquire first transmission information obtained by transmitting an image of the piping from a first shooting direction in which two opposing sides of the piping are included in the transmission path, and second transmission information obtained by transmitting an image of the piping from a second shooting direction opposite the first shooting direction, and to output information based on the difference between the first transmission information and the second transmission information.

[0012] According to the technology of the present disclosure, it is possible to easily inspect piping even when the imaging results contain a mixture of information from two sides.

[0013] 1 is a diagram showing an example of a schematic configuration of a piping inspection system 10 according to the present embodiment. FIG. 1 is a diagram showing an example of an imaging system in a case where a first imaging direction and a second imaging direction are not directly opposite to each other. FIG. 2 is a diagram showing a comparative example of an imaging system. FIG. 3 is a diagram showing an example of a hardware configuration of a piping inspection device 100 according to the present embodiment. FIG. 4 is a diagram showing an example of a functional configuration of the piping inspection device 100 according to the first embodiment. FIG. 5 is a diagram showing an example of a flow of a piping inspection method executed by the piping inspection device 100 according to the first embodiment. FIG. 6 is a diagram showing an example of a difference vector output by the piping inspection device 100 according to the first embodiment. FIG. 7 is a diagram showing another example of an imaging system. FIG. 8 is a diagram showing another example of a difference vector output by the piping inspection device 100 according to the first embodiment. FIG. 9 is a diagram showing an example of a functional configuration of the piping inspection device 100 according to the second embodiment. FIG. 10 is a diagram showing an example of a flow of a piping inspection method executed by the piping inspection device 100 according to the second embodiment. FIG. 11 is a diagram showing an example of a functional configuration of the piping inspection device 100 according to the third embodiment. FIG. 12 is a diagram showing an example of a profile output by the piping inspection device 100 according to the third embodiment. FIG. 13 is a diagram showing a schematic diagram illustrating movement of wall thinning information. FIG. 14 is a diagram showing an example of a functional configuration of the piping inspection device 100 according to the fourth embodiment. FIG. 15 is a diagram showing an example of an imaging plan. FIG. 16 is a diagram showing another example of an imaging plan. FIG. 10 is a diagram showing an example of a region of transmission information when spiral photography is performed twice; FIG. 11 is a diagram showing an example of a report output by the piping inspection device 100 according to the fourth embodiment; FIG. 12 is a diagram showing an example of a region of transmission information when spiral photography is performed twice; FIG. 13 is a diagram showing an example of a report output by the piping inspection device 100 according to the fourth embodiment;

[0014] An example of an embodiment of the present disclosure will be described below with reference to the drawings. In each drawing, the same or equivalent components and parts are designated by the same reference numerals. Furthermore, the dimensional proportions in the drawings are exaggerated for the sake of explanation and may differ from the actual proportions.

[0015] 1 is a diagram showing an example of a schematic configuration of a piping inspection system 10 according to this embodiment. The piping inspection system 10 is a system that inspects for abnormalities in a piping 20. Below, an example will be described in which the piping inspection system 10 inspects for thinning that occurs in the inner wall of the piping 20.

[0016] Wall thinning refers to a phenomenon in which the initial thickness of a pipe through which a fluid flows gradually decreases with use. If the wall thinning progresses, the fluid may leak, causing a serious accident. In order to prevent such accidents, it is important to inspect the wall thinning of the pipe 20. Therefore, the pipe inspection system 10 inspects wall thinning that occurs on the inner wall of the pipe 20. However, the pipe inspection system 10 may also inspect any abnormality that may occur in the pipe 20, such as wall thinning that occurs on the outer wall of the pipe 20, cracks that occur on the inner or outer wall of the pipe 20, or rust that occurs on the inner or outer wall of the pipe 20.

[0017] The piping inspection system 10 includes a communication means 50, a piping inspection device 100, and an imaging system.

[0018] The communication means 50 connects multiple computers so that they can communicate with each other. In this figure, the communication means 50 connects between a computer (not shown) provided in the imaging system (e.g., a computer of the imaging device) and the piping inspection device 100. The communication means 50 may be the Internet, for example. However, the communication means 50 may be any means capable of connecting multiple computers so that they can communicate with each other, such as a LAN, a WAN, or an intranet, and the connection form may be either wired or wireless. Furthermore, if the piping inspection device 100 is incorporated into the imaging system (e.g., if the piping inspection device 100 is configured integrally with the imaging device), the piping inspection system 10 may not be equipped with the communication means 50.

[0019] The piping inspection device 100 acquires two pieces of transmission information obtained by transmitting images of the piping 20 from different imaging directions and outputs information corresponding to the difference between the two pieces of transmission information. This figure shows an example in which the piping inspection device 100 is implemented using cloud computing. In this case, the piping inspection device 100 may acquire the transmission information from the imaging system via communication means 50, which is the Internet, and provide information corresponding to the difference to various computers connected to the Internet. However, this is not limited to this. The piping inspection device 100 may be implemented by an edge server at the site (e.g., a plant) where the piping 20 is installed, or may be implemented as a partial function of an imaging device.

[0020] In the imaging system, the pipe 20 is radiographed from different imaging directions. This figure shows the imaging system in a cross-section of the pipe 20. Here, the first side surface 21 and the second side surface 22 are an example of two opposing side surfaces. In this way, the two opposing side surfaces may be side surfaces at different positions in the circumferential direction of the pipe 20. In the imaging system, the radiation source 30 and the panel 40 are disposed opposite each other with the pipe 20 in between. Then, radiation is irradiated from the radiation source 30, and the amount of radiation that has passed through the pipe 20 is detected by the panel 40, thereby performing radiography of the pipe 20. Here, any type of radiation may be used, such as α rays, β rays, neutron rays, γ rays, or X-rays. However, it is preferable to use X-rays, which have high penetrating properties, when inspecting the pipe 20.

[0021] The imaging system shown on the left in the figure shows how transmission imaging of the pipe 20 is performed from a first imaging direction. In this case, the radiation source 30 is positioned above the pipe 20 in the figure, and the panel 40 is positioned opposite the below the pipe 20 in the figure, and transmission imaging of the pipe 20 is performed in the first imaging direction from top to bottom in the figure.

[0022] The imaging system shown on the right side of the figure shows how transmission imaging of the pipe 20 is performed from a second imaging direction opposite to the first imaging direction. In this case, the radiation source 30 is placed below the pipe 20 in the figure, and the panel 40 is placed opposite to the above the pipe 20 in the figure, and transmission imaging of the pipe 20 is performed in the second imaging direction from bottom to top in the figure.

[0023] When the pipe 20 is photographed through transmission in this manner, the first side surface 21 and the second side surface 22 are included in the transmission path from the radiation source 30 to the panel 40. Therefore, the photographing result contains a mixture of information on the two sides, the first side surface 21 and the second side surface 22. For this reason, even if thinning occurs on the second side surface 22, for example, the information on the second side surface 22 may be buried in the information on the first side surface 21, making it difficult to detect the thinning. Therefore, the pipe inspection device 100 according to this embodiment makes it possible to easily inspect the pipe 20 by utilizing the difference in the photographing results due to differences in the photographing direction, even when the photographing result contains a mixture of information on the two sides.

[0024] 1 shows an example in which the first imaging direction and the second imaging direction are directly opposite to each other, but the first imaging direction and the second imaging direction do not necessarily have to be directly opposite to each other.

[0025] 2 is a diagram showing an example of an imaging system in which the first imaging direction and the second imaging direction are not directly opposite each other. As shown in this figure, the first imaging direction and the second imaging direction do not necessarily have to be directly opposite each other. In this case, it is sufficient that the first side surface 21 included in the transmission path when imaging from the first imaging direction and the first side surface 21 included in the transmission path when imaging from the second imaging direction at least partially overlap, and that the second side surface 22 included in the transmission path when imaging from the first imaging direction and the second side surface 22 included in the transmission path when imaging from the second imaging direction at least partially overlap. Therefore, the term "facing" may be interpreted to include cases where one side and the other side are not strictly facing each other.

[0026] 1 shows a state in which transmission imaging of the pipe 20 is performed so that two side surfaces (first side surface 21 and second side surface 22 in FIG. 1) are approximately perpendicular to the transmission path from the radiation source 30 to the panel 40. Such an imaging system is referred to as a double-wall imaging system.

[0027] FIG. 3 shows comparative examples of imaging systems. The left side of the figure shows Comparative Example 1, in which transmission imaging of the pipe 20 is performed so that one side (the third side 23 in this figure) is approximately parallel to the transmission path from the radiation source 30 to the panel 40. The center of the figure shows Comparative Example 2, in which transmission imaging of the pipe 20 is performed so that two side surfaces (the third side 23 and the fourth side 24 in this figure) are approximately parallel to the transmission path from the radiation source 30 to the panel 40. Comparative Examples 1 and 2 require a larger space than the double-wall imaging system according to this embodiment. The right side of the figure shows Comparative Example 3, in which the radiation source 30 is installed inside the pipe 20 and transmission imaging of the pipe 20 is performed so that one side surface (the second side 22 in this figure) is approximately perpendicular to the transmission path from the radiation source 30 to the panel 40. Although Comparative Example 3 requires a smaller space than the double-wall imaging system according to this embodiment, it still requires that the radiation source 30 be installed inside the pipe 20. Therefore, the reality is that there are many sites where imaging systems such as those in Comparative Examples 1 to 3 cannot be realized.

[0028] Therefore, in this embodiment, a double-wall imaging system is adopted. This allows the required space to be smaller than in Comparative Examples 1 and 2, and also eliminates the need to install the radiation source 30 inside the pipe 20 as in Comparative Example 3, making it feasible in a variety of sites. In the double-wall imaging system, it is preferable to perform transmission imaging such that the transmission path from the radiation source 30 to the panel 40 includes the first side surface 21 and the second side surface 22, but does not include the third side surface 23 and the fourth side surface 24, thereby minimizing the distance between the radiation source 30 and the panel 40. However, in this embodiment, it is not essential that the transmission path from the radiation source 30 to the panel 40 does not include the third side surface 23 and the fourth side surface 24. This embodiment is also applicable to cases where the transmission path includes the third side surface 23 and the fourth side surface 24 in addition to the first side surface 21 and the second side surface 22.

[0029] 4 is a diagram showing an example of the hardware configuration of the piping inspection device 100 according to this embodiment. The piping inspection device 100 includes a CPU 101, a ROM 102, a RAM 103, a storage 104, a communication interface 105, and a user interface 106. These components are connected to each other via a bus 109 so as to be able to communicate with each other.

[0030] The CPU 101 is a central processing unit that executes various programs and controls each component. The ROM 102 stores various programs and various data. The RAM 103 temporarily stores programs or data as a working area. The storage 104 is composed of an HDD (Hard Disk Drive) or an SSD (Solid State Drive) and stores various programs including the operating system and various data.

[0031] The communication interface 105 is an interface that allows the piping inspection device 100 to communicate with other devices. The user interface 106 is an input / output interface that allows the piping inspection device 100 to exchange information with a user. The user interface 106 may include a touch panel, keyboard, mouse, microphone, etc. as input devices, and may include a monitor, printer, speaker, etc. as output devices.

[0032] 5 is a diagram showing an example of the functional configuration of the piping inspection device 100 according to the first embodiment. The piping inspection device 100 according to the first embodiment includes a transmission information acquisition unit 111, a difference calculation unit 112, and an output unit 113. These functional configurations are realized by the CPU 101 reading out a piping inspection program from the ROM 102 or the storage 104, and expanding and executing the program in the RAM 103. The same applies to other functional configurations described below.

[0033] As a transmission information acquisition unit 111, the CPU 101 acquires first transmission information obtained by transmitting an image of the piping 20 from a first shooting direction in which two opposing sides of the piping 20 are included in the transmission path, and second transmission information obtained by transmitting an image of the piping 20 from a second shooting direction opposite the first shooting direction.

[0034] The CPU 101 functions as a difference calculation unit 112 to calculate the difference between the first transmission information and the second transmission information acquired by the transmission information acquisition unit 111 .

[0035] The CPU 101 functions as the output unit 113 and outputs information based on the difference between the first transmission information and the second transmission information calculated by the difference calculation unit 112 .

[0036] 6 is a diagram showing an example of the flow of a pipe inspection method executed by the pipe inspection device 100 according to the first embodiment. This flow is executed by the CPU 101 reading out a pipe inspection program from the ROM 102 or the storage 104, and expanding and executing the program in the RAM 103. The same applies to other flows described later.

[0037] In step S121, the CPU 101 acquires first transmission information obtained by transmitting an image of the pipe 20 from a first imaging direction in which two opposing side surfaces of the pipe 20 are included in the transmission path, and second transmission information obtained by transmitting an image of the pipe 20 from a second imaging direction opposite to the first imaging direction. At this time, the CPU 101 may acquire the first transmission information and the second transmission information in real time from the imaging system, or may acquire them from a database in which transmission information captured in the past is stored.

[0038] Here, if no thinning has occurred on any of the side surfaces of the pipe 20, the imaging results will be the same regardless of the direction from which the transmission imaging is performed. However, for example, if thinning has occurred on the second side surface 22 of the pipe 20, the imaging results will differ between when the pipe 20 is transmitted through the first imaging direction and when the pipe 20 is transmitted through the second imaging direction. That is, when the pipe 20 is imaged from the first imaging direction, the first side surface 21, where no thinning has occurred, is located in front of the radiation source 30, and the second side surface 22, where thinning has occurred, is located in back of the radiation source 30. On the other hand, when the pipe 20 is imaged from the second imaging direction, the second side surface 22, where thinning has occurred, is located in front of the radiation source 30, and the first side surface 21, where no thinning has occurred, is located in back of the radiation source 30. Here, because the radiation irradiated from the radiation source 30 spreads radially, the degree of penetration on the front side as viewed from the radiation source 30 has a stronger influence than the degree of penetration on the back side. Therefore, a difference occurs between the first transmission information obtained by transmitting an image of the pipe 20 from the first imaging direction and the second transmission information obtained by transmitting an image of the pipe 20 from the second imaging direction. In this way, when the thickness of the pipe 20 is not uniform between the opposing side surfaces, the CPU 101 acquires two pieces of transmission information that differ depending on the imaging direction.

[0039] In step S122, the CPU 101 calculates the difference between the first transparency information and the second transparency information acquired in step S121. Here, the transparency information is vector information having regions such as areas and lines. The CPU 101 may generate a first transparency vector by arranging the transparency levels for each region included in the first transparency information in a row. Similarly, the CPU 101 may generate a second transparency vector by arranging the transparency levels for each region included in the second transparency information in a row. The CPU 101 may then calculate a difference vector by subtracting the second transparency vector from the first transparency vector.

[0040] In this case, the fluid flowing through the pipe 20 is not necessarily uniform, and the fluid may be biased in one direction due to the influence of gravity, etc. Therefore, the CPU 101 may calculate the difference vector by correcting the subtraction result with a predetermined correction value.

[0041] In step S123, the CPU 101 outputs information based on the difference between the first transmission information and the second transmission information calculated in step S122. For example, the CPU 101 may output the information by displaying a graph on a monitor in which the difference vector calculated in step S122 is plotted.

[0042] 7 is a diagram showing an example of a difference vector output by the piping inspection device 100 according to the first embodiment. In this diagram, the horizontal axis represents the area. Also, in this diagram, the vertical axis represents the degree of transparency, in this case, the difficulty of transparency, where a larger value means less transparency and a smaller value means easier transparency. Also, in this diagram, the dotted line represents the first transparency vector, and the dashed line represents the second transparency vector. And, in this diagram, the solid line represents the difference vector.

[0043] Here, the first transmission information is the result of transmission photography performed so that the first side surface 21 is on the near side as viewed from the radiation source 30. Therefore, the influence of thinning located on the far side as viewed from the radiation source 30 is small, and as a result, the first transmission vector has a relatively large degree of transmission (difficulty of transmission). On the other hand, the second transmission information is the result of transmission photography performed so that the second side surface 22 is on the near side as viewed from the radiation source 30. Therefore, the influence of thinning located on the near side as viewed from the radiation source 30 is large, and as a result, the second transmission vector has a relatively small degree of transmission (difficulty of transmission).

[0044] Therefore, the difference vector obtained by subtracting the second transmission vector from the first transmission vector is not a zero vector. The piping inspection device 100 takes advantage of the fact that the information on the front side is emphasized relative to the information on the back side in this way, and outputs information corresponding to the difference between the transmission information captured from different directions, thereby providing information that contributes to the detection of wall thinning.

[0045] In the above explanation, an example is given of a case where widespread thinning occurs on the second side surface 22, but the technology according to this embodiment can also be applied to cases where localized thinning occurs.

[0046] Fig. 8 is a diagram showing another example of the imaging system. While Fig. 1 shows an example in which widespread thinning has occurred on the second side surface 22 of the pipe 20, as shown in this figure, it is assumed that local thinning has occurred on the second side surface 22 of the pipe 20. Even in this case, the pipe inspection device 100 can output the difference vector shown in the following figure by executing the flow of Fig. 6.

[0047] 9 is a diagram showing another example of the difference vector output by the piping inspection device 100 according to the first embodiment. The definitions of the axes and lines are the same as those in FIG. 7, and therefore will not be described here. As shown in this figure, the piping inspection device 100 can handle not only widespread wall thinning but also local wall thinning.

[0048] In the above description, a case where the piping inspection device 100 outputs a difference vector between the first transmission vector and the second transmission vector as the difference between the first transmission information and the second transmission information has been described as an example, but the present invention is not limited to this. For example, if the first transmission information and the second transmission information are image data, the piping inspection device 100 may output a difference image between the first transmission image and the second transmission image as the difference between the first transmission information and the second transmission information.

[0049] As described above, it is conceivable to use transmission information captured by a double-wall imaging system as a technique for non-destructively inspecting the piping 20. Such a double-wall imaging system can reduce the required space and does not require the radiation source 30 to be placed inside the piping 20, making it feasible to implement in a variety of sites.

[0050] However, when the radiation source 30 and the panel 40 are positioned opposite each other across the piping 20 and the piping 20 is photographed through the radiation source 30 and the photographed image contains a mixture of information from the two opposing sides of the piping 20, which can make it difficult to inspect the piping 20.

[0051] Therefore, the piping inspection device 100 according to the first embodiment acquires first transmission information obtained by transmitting an image of the piping 20 from a first shooting direction in which two opposing sides of the piping 20 are included in the transmission path, and second transmission information obtained by transmitting an image of the piping 20 from a second shooting direction opposite the first shooting direction, and outputs information based on the difference between the first transmission information and the second transmission information.

[0052] As a result, with the piping inspection device 100 according to the first embodiment, when the wall thickness of the piping 20 is not uniform on two opposing side surfaces, the difference between the two photographed results can be expressed, thereby providing information that is useful for detecting wall thinning. Therefore, with the piping inspection device 100 according to the first embodiment, even when information on the two sides is mixed in the photographed results, the inspection of the piping 20 can be facilitated.

[0053] 10 is a diagram showing an example of the functional configuration of a piping inspection device 100 according to the second embodiment. In the first embodiment, an example is shown in which the piping inspection device 100 outputs the calculated difference itself as the inspection result. In the second embodiment, the piping inspection device 100 outputs a determination result based on the difference as the inspection result. The piping inspection device 100 according to the second embodiment further includes a statistical value calculation unit 114, an abnormality presence / absence determination unit 115, and an abnormal side determination unit 116 in addition to the functional configuration of the piping inspection device 100 according to the first embodiment.

[0054] The CPU 101 functions as a statistical value calculation unit 114 to calculate a statistical value of the difference calculated by the difference calculation unit 112 .

[0055] The CPU 101 functions as an abnormality determination unit 115 to determine whether there is a possibility of an abnormality in the piping 20 based on the magnitude of the statistical value calculated by the statistical value calculation unit 114 .

[0056] The CPU 101 functions as an abnormal side determination unit 116 to determine which side of the pipe 20 may be abnormal based on the positive or negative value of the statistical value calculated by the statistical value calculation unit 114 .

[0057] 11 is a diagram showing an example of the flow of a piping inspection method executed by the piping inspection device 100 according to the second embodiment. Steps S121 and S122 may be the same processes as those in FIG. 6, and therefore, description thereof will be omitted here.

[0058] In step S124, the CPU 101 calculates a statistical value of the difference calculated in step S122. For example, the CPU 101 may calculate an average value obtained by averaging each element of the difference vector calculated in step S122, i.e., the transparency for each region, as the statistical value. Alternatively, or in addition, the CPU 101 may calculate a sum obtained by adding the transparency for each region as the statistical value. In this case, the average value or sum may be a weighted average value or weighted sum. Such an average value or sum can be regarded as a numerical value (scalar value) that quantifies the possibility of an abnormality (here, thinning).

[0059] In step S125, the CPU 101 determines whether or not there is a possibility of an abnormality in the piping 20 based on the magnitude of the statistical value calculated in step S124. In the second embodiment, the CPU 101 determines whether or not there is a possibility of an abnormality in the piping 20 based on the result of comparing the magnitude of the statistical value with a predetermined threshold. For example, the CPU 101 may determine whether or not the absolute value of the statistical value is equal to or greater than a predetermined threshold. If the CPU 101 determines that the absolute value of the statistical value is not equal to or greater than the threshold (No), the CPU 101 determines that there is no possibility of an abnormality in the piping 20. Then, the CPU 101 proceeds to step S126.

[0060] In step S126, CPU 101 outputs a message indicating that there is no possibility of an abnormality in piping 20. For example, CPU 101 may output the statistical value calculated in step S124 along with a message indicating that there is no possibility of an abnormality. In this way, piping inspection device 100 can notify the user that there is no possibility of an abnormality and provide the user with objective grounds for determining that there is no possibility of an abnormality.

[0061] On the other hand, if it is determined that the absolute value of the statistical value is equal to or greater than the threshold value (Yes), the CPU 101 determines that there is a possibility of an abnormality in the piping 20. Then, the CPU 101 advances the process to step S127.

[0062] In step S127, CPU 101 outputs a message indicating that there is a possibility of an abnormality in piping 20. For example, CPU 101 may output the statistical value calculated in step S124 along with a message indicating that there is a possibility of an abnormality. In this way, piping inspection device 100 can notify the user that there is a possibility of an abnormality and provide the user with objective grounds for determining that there is a possibility of an abnormality.

[0063] In step S128, the CPU 101 determines a side of the pipe 20 that may have an abnormality based on the positive or negative statistical value calculated in step S124. For example, as described above, assume that the transmittance indicates the degree of transmittance, with a larger value indicating less transmittance and a smaller value indicating more transmittance. Furthermore, assume that, when calculating the difference between the first transmittance information and the second transmittance information, the first transmittance vector based on the first transmittance information is subtracted as the minuend, and the second transmittance vector based on the second transmittance information is subtracted as the subtrahend. In this case, if the statistical value of the difference is positive, the CPU 101 determines that the second side surface 22, which is the side surface on the far side in the first imaging direction (the near side in the second imaging direction), is a side surface that may have wall thinning. On the other hand, if the statistical value of the difference is negative, the CPU 101 determines that the first side 21, which is the side on the front side in the first shooting direction (the back side in the second shooting direction), is a side that may be subject to thinning.

[0064] In step S129, CPU 101 outputs information about the side surface that may be abnormal, as determined in step S128. For example, if second side surface 22 is determined to be a side surface that may be thinning, CPU 101 may output information that identifies second side surface 22. In this case, if numbers are assigned to equally spaced positions in the circumferential direction of pipe 20, CPU 101 may output the number assigned to second side surface 22 as information about the side surface that may be abnormal.

[0065] In this way, the piping inspection device 100 according to the second embodiment calculates a statistical value of the difference between the first transmission information and the second transmission information. This allows the piping inspection device 100 according to the second embodiment to quantify the difference. At this time, the piping inspection device 100 may determine whether or not there is a possibility of an abnormality in the piping based on the magnitude of the statistical value. This not only eliminates the need for the user to make a judgment, but also prevents variations in the judgment results depending on the user's level of proficiency, etc. Furthermore, the piping inspection device 100 may determine which side of the piping may have an abnormality based on the positive or negative value of the statistical value. This allows the piping inspection device 100 to inform the user of which side may have an abnormality, even when information from two sides is mixed in the imaging results.

[0066] 12 is a diagram showing an example of the functional configuration of the piping inspection device 100 according to the third embodiment. In the above-described embodiment, an example has been shown in which the piping inspection device 100 outputs inspection results under one imaging condition. In the third embodiment, the piping inspection device 100 outputs inspection results under a plurality of imaging conditions. The piping inspection device 100 according to the third embodiment further includes an imaging condition acquisition unit 117 in addition to the functional configuration included in the piping inspection device 100 according to the second embodiment.

[0067] In the third embodiment, the CPU 101, as the transmission information acquisition unit 111, acquires multiple sets of first transmission information and second transmission information when transmission imaging of the piping 20 is performed under different imaging conditions. The imaging condition may be, for example, an imaging position on the piping 20. Examples of such imaging positions include a circumferential position and an axial position on the piping 20. Therefore, when transmission imaging is performed at multiple imaging positions where at least one of the circumferential position and the axial position on the piping 20 is different, the CPU 101 may acquire sets of first transmission information and second transmission information for each of the multiple imaging positions.

[0068] The CPU 101, as the imaging condition acquisition unit 117, acquires imaging conditions indicating the conditions under which the first transmission information and the second transmission information were photographed. For example, when acquiring the set of the first transmission information and the second transmission information, the CPU 101 may acquire information on at least one of the circumferential position and the axial position of the pipe 20 whose transmission image was taken, and preferably both of these.

[0069] In the third embodiment, the CPU 101, functioning as the difference calculation unit 112, calculates a difference for each shooting condition. Similarly, the CPU 101, functioning as the statistical value calculation unit 114, calculates a statistical value for each shooting condition. Similarly, the CPU 101, functioning as the abnormality presence / absence determination unit 115, determines whether or not there is a possibility of an abnormality for each shooting condition. Similarly, the CPU 101, functioning as the abnormal side determination unit 116, determines a side that may be abnormal for each shooting condition. Then, the CPU 101, functioning as the output unit 113, outputs at least one of the difference, the statistical value, or the determination result for each shooting condition.

[0070] 13 is a diagram showing an example of a profile output by the piping inspection device 100 according to the third embodiment. The left side of the figure shows a cross-sectional view of the piping 20. As shown in the left side of the figure, numbers (e.g., #1 to #8) may be assigned to positions equally spaced apart in the circumferential direction of the piping 20.

[0071] The right side of this figure shows a profile. In the right side of this figure, the vertical axis represents the circumferential position of the pipe 20. In the right side of this figure, the horizontal axis represents the axial position of the pipe 20. For example, the CPU 101 may output a profile by plotting statistical values ​​calculated for each of a plurality of circumferential positions and a plurality of axial positions. In this case, if the statistical values ​​in opposite directions, such as #1 and #5 or #2 and #6, only differ in positive and negative sign, the CPU 101 may omit the semicircular information by, for example, showing only #1 to #4. Furthermore, while this figure shows a two-dimensional profile including both the circumferential position and the axial position as an example, the CPU 101 may output a one-dimensional profile including only either the circumferential position or the axial position. In this way, when outputting information based on the difference for each imaging position, the CPU 101 may output information based on the difference for each circumferential position, for each axial position, or for both the circumferential position and the axial position. Furthermore, in the above description, the CPU 101 plots statistical values ​​as an example, but the CPU 101 may plot the determination result of whether or not there is a possibility of an abnormality.

[0072] 14 is a diagram that schematically illustrates the shifting of wall-thinning information. The pipe 20 has a length in the axial direction, and the user is interested in the axial position of the wall-thinning in the pipe 20. However, as shown in this figure, when the photographic results of the pipe 20 are continuously viewed from above in the axial direction, the wall-thinning information shifts, making it impossible to identify the correct axial position where the wall-thinning has occurred from the photographic results themselves.

[0073] In contrast, the piping inspection device 100 according to the third embodiment acquires multiple sets of first transmission information and second transmission information obtained when the piping 20 is photographed under different photographing conditions, and outputs information based on the difference for each photographing condition. As a result, the piping inspection device 100 according to the third embodiment can output information based on the difference in association with the photographing condition. In this case, the piping inspection device 100 may output information based on the difference for each photographing position on the piping 20, for example, for each circumferential position or each axial position. As a result, the piping inspection device 100 can output inspection results for each of the multiple photographing positions. Therefore, the piping inspection device 100 can output inspection results for different circumferential positions at the same axial position, as well as inspection results for different axial positions at the same circumferential position, thereby providing a user with information for identifying the location of an abnormality in the piping 20.

[0074] In the above description, the case where the imaging condition is the imaging position in the piping 20 has been described as an example, but the imaging condition may also be the imaging time when the piping 20 is imaged through the imaging. In this case, the CPU 101 may output information based on the difference for each imaging time. As a result, the piping inspection device 100 outputs inspection results obtained at different imaging times at the same imaging position, and therefore can provide the user with information for identifying changes over time in an abnormality occurring in the piping 20.

[0075] As described above, in the third embodiment, calculation processing is performed for each of the multiple imaging conditions. Therefore, in the third embodiment, multiple calculation results are obtained. Therefore, these multiple calculation results can also be used to determine whether or not there is a possibility of an abnormality. That is, in the second embodiment, an example was shown in which the CPU 101 determines whether or not there is a possibility of an abnormality in the piping 20 based on the result of comparing the magnitude of a statistical value with a predetermined threshold. However, in the third embodiment, the CPU 101 may determine whether or not there is a possibility of an abnormality in the piping 20 based on an outlier in the magnitude of the statistical value. For example, the CPU 101 may determine whether or not there is a possibility of an abnormality in the piping 20 if, as a result of calculating the magnitude of multiple statistical values ​​for each of the multiple imaging conditions, an outlier is found among the multiple statistical values. Note that the outlier can be calculated using a known method, such as the average and variance. As a result, the piping inspection device 100 can determine whether or not there is a possibility of an abnormality based on a relative criterion, instead of an absolute criterion.

[0076] 15 is a diagram showing an example of the functional configuration of the piping inspection device 100 according to the fourth embodiment. In the above-described embodiment, the case where the photography of the piping 20 and the inspection of the piping 20 are independent of each other has been shown as an example. In the fourth embodiment, the piping inspection device 100 coordinates the photography of the piping 20 with the inspection of the piping 20. The piping inspection device 100 according to the fourth embodiment further includes an imaging planning unit 118 and an imaging instruction unit 119 in addition to the functional configuration included in the piping inspection device 100 according to the third embodiment.

[0077] The CPU 101, as the imaging planning unit 118, creates an imaging plan for performing transmission imaging of the pipe 20 under different imaging conditions. The imaging of the pipe 20 may be performed manually based on the imaging plan, or may be performed automatically by a self-propelled robot such as a drone. Below, an example will be described in which a self-propelled imaging robot that can move along the pipe 20 is used.

[0078] The imaging plan may include imaging positions (e.g., circumferential positions and axial positions) for imaging the piping 20 and a movement schedule for moving to different imaging positions.

[0079] The CPU 101, as the imaging instruction unit 119, outputs an instruction to remotely operate the imaging robot in accordance with the imaging plan created by the imaging planning unit 118. In accordance with this, the imaging robot performs transmission imaging of the piping 20 while moving through the piping 20. As a result, the CPU 101, as the transmission information acquisition unit 111, can acquire multiple sets of first transmission information and second transmission information when transmission imaging of the piping 20 is performed in accordance with the imaging plan.

[0080] FIG. 16 is a diagram showing an example of an imaging plan. This diagram shows a case where the imaging robot moves independently in two directions. For example, the imaging robot may move circumferentially at axial position (1) and sequentially perform imaging at circumferential positions #1 to #8. Next, the imaging robot may move axially. Then, the imaging robot may move circumferentially at axial position (2) and sequentially perform imaging at circumferential positions #1 to #8. In this way, the imaging robot may move independently in the circumferential and axial directions along the pipe 20 and perform transmission imaging of the pipe 20 at multiple circumferential and axial positions. The imaging plan may be, for example, a plan to perform transmission imaging of the pipe 20 at different imaging positions while moving independently in the circumferential and axial directions along the pipe 20.

[0081] 17 is a diagram showing another example of an imaging plan. This diagram shows a case where an imaging robot moves in a spiral manner. For example, the imaging robot may move in a spiral manner along the pipe 20 and take transmission images of the pipe 20 at multiple circumferential positions and multiple axial positions. The imaging plan may be, for example, a plan in which the imaging robot moves in a spiral manner along the pipe 20 and takes transmission images of the pipe 20 at different imaging positions.

[0082] When creating an imaging plan, it is necessary to take note that the area in front of the radiation source 30 is smaller than the area behind it.

[0083] 18 is a diagram schematically illustrating that the area in front of the radiation source 30 is narrower than the area in back of the radiation source 30. As shown in this figure, even if an imaging plan is created so that the area in back of the radiation source 30 is dense, the area in front of the radiation source 30 may be sparse, and it may be impossible to acquire a set of opposing first and second transmission information. Therefore, the CPU 101 may create an imaging plan based on the area in front of the radiation source 30 (i.e., so that the area in front of the radiation source 30 is dense). In this case, the areas in back of the radiation source 30 may overlap each other.

[0084] In addition, when creating an imaging plan for taking transmission images of the pipe 20 while moving spirally along the pipe 20, it is necessary to take note that there will be a discrepancy between the area in front of the radiation source 30 and the area behind it.

[0085] 19 is a diagram showing a schematic diagram of a discrepancy between the front and rear regions in the transmission information obtained by spiral imaging. When spiral imaging is performed, as shown in this figure, a discrepancy occurs between the front region and the rear region as viewed from the radiation source 30. In this case, it is considered that two opposing transmission information pieces cannot be obtained in a single spiral imaging. Therefore, the CPU 101 may create an imaging plan to perform multiple spiral imaging operations.

[0086] 20 is a diagram showing an example of transmission information regions when two spiral imaging sessions are performed. In this figure, vertical stripes indicate the region of near-side transmission information obtained by the first spiral imaging session. Also, horizontal stripes indicate the region of near-side transmission information obtained by the second spiral imaging session. As a result, for example, two sets of transmission information facing each other are obtained by the near-side transmission information obtained by the first spiral imaging session and the far-side transmission information obtained by the second spiral imaging session, and two sets of transmission information facing each other are obtained by the near-side transmission information obtained by the second spiral imaging session and the far-side transmission information obtained by the first spiral imaging session.

[0087] 21 is a diagram showing an example of a report output by the piping inspection device 100 according to the fourth embodiment. As described above, in the fourth embodiment, the CPU 101 creates an imaging plan for transmitting imaging of the piping 20. Therefore, the CPU 101 may output a report in which a drawing of the piping 20 obtained when the imaging plan is generated is associated with a profile. In this case, when a user places a cursor on a region of interest in the piping 20 by operating a mouse or the like, the CPU 101 may output the profile in the region of interest by displaying it on a monitor, for example. In this way, the CPU 121 may output information based on the difference in association with the imaging plan, for example.

[0088] In this way, the piping inspection device 100 according to the fourth embodiment generates an imaging plan for photographing the piping 20 through transmission imaging at different imaging positions, and acquires multiple sets of first transmission information and second transmission information when the piping 20 is photographed through transmission imaging according to the imaging plan. This allows the piping inspection device 100 according to the fourth embodiment to coordinate the imaging of the piping 20 with the inspection of the piping 20. In this case, the piping inspection device 100 may output information based on the difference in association with the imaging plan. This allows the piping inspection device 100 to provide the user with inspection results according to the imaging plan.

[0089] In the above-described embodiments, the term "processor" refers to a processor in a broad sense, and includes a general-purpose processor (e.g., a CPU) and a dedicated processor (e.g., a GPU: Graphics Processing Unit, an ASIC: Application Specific Integrated Circuit, an FPGA: Field Programmable Gate Array, a programmable logic device, etc.).

[0090] Furthermore, the operations of the processors in the above embodiments may be performed not only by a single processor but also by multiple processors located at physically separate locations working together. Furthermore, the order of the operations of the processors is not limited to the order described in the above embodiments, and may be changed as appropriate.

[0091] Furthermore, although the piping inspection device 100 according to the above embodiment has been described as being configured by a single device as an example, it may be configured by a plurality of devices.

[0092] Furthermore, the processes performed by the piping inspection device 100 according to the above-described embodiment may be processes performed by software, processes performed by hardware, or a combination of both. Furthermore, the processes performed by each unit of the piping inspection device 100 may be stored as a program on a storage medium and distributed.

[0093] Furthermore, the present disclosure is not limited to the above, and it goes without saying that various modifications can be made without departing from the spirit of the present disclosure.

[0094] The disclosure of Japanese Patent Application No. 2023-137262, filed on August 25, 2023, is incorporated herein by reference in its entirety. In addition, all documents, patent applications, and technical standards described herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard were specifically and individually indicated to be incorporated by reference.

[0095] The following supplementary notes are further disclosed with respect to the above embodiments. (Supplementary Note 1) A piping inspection device including a processor, the processor acquiring first transmission information obtained by transmitting an image of a piping from a first imaging direction in which two opposing side surfaces of the piping are included in a transmission path, and second transmission information obtained by transmitting an image of the piping from a second imaging direction opposite to the first imaging direction, and outputting information based on a difference between the first transmission information and the second transmission information. (Supplementary Note 2) The piping inspection device according to Supplementary Note 1, wherein the processor calculates a statistical value of the difference. (Supplementary Note 3) The piping inspection device according to Supplementary Note 2, wherein the processor determines whether or not there is a possibility of an abnormality in the piping based on the magnitude of the statistical value. (Supplementary Note 4) The piping inspection device according to Supplementary Note 2 or 3, wherein the processor determines whether or not there is a possibility of an abnormality in the piping based on a result of comparing the magnitude of the statistical value with a predetermined threshold. (Supplementary Note 5) The piping inspection device according to Supplementary Note 3 or 4, wherein the processor determines whether or not there is a possibility of an abnormality in the piping based on an outlier in the magnitude of the statistical value. (Supplementary Note 6) The piping inspection device according to any one of Supplements 2 to 5, wherein the processor determines an aspect of the piping that may have an abnormality based on the positive or negative of the statistical value. (Supplementary Note 7) The piping inspection device according to any one of Supplements 1 to 6, wherein the processor acquires a plurality of sets of the first transmission information and the second transmission information when the piping is photographed through transmission under different photographing conditions, and outputs information based on the difference for each of the photographing conditions. (Supplementary Note 8) The piping inspection device according to Supplementary Note 7, wherein the photographing condition is a photographing position on the piping, and the processor outputs the information based on the difference for each of the photographing positions. (Supplementary Note 9) The piping inspection device according to Supplementary Note 8, wherein the photographing position is a circumferential position on the piping, and the processor outputs the information based on the difference for each of the circumferential positions. (Supplementary Note 10) The piping inspection device according to Supplementary Note 8 or 9, wherein the photographing position is an axial position on the piping, and the processor outputs the information based on the difference for each of the axial positions.(Supplementary Note 11) The piping inspection device according to any one of Supplements 8 to 10, wherein the processor generates an imaging plan for photographing the piping through transmission images at different imaging positions, and obtains a plurality of sets of the first transmission information and the second transmission information when the piping is photographed through transmission images in accordance with the imaging plan. (Supplementary Note 12) The piping inspection device according to Supplementary Note 11, wherein the imaging plan is a plan for photographing the piping through transmission images at different imaging positions while moving independently in a circumferential direction and an axial direction along the pipe. (Supplementary Note 13) The piping inspection device according to Supplementary Note 11, wherein the imaging plan is a plan for photographing the piping through transmission images at different imaging positions while moving in a spiral manner along the pipe. (Supplementary Note 14) The piping inspection device according to any one of Supplements 11 to 13, wherein the processor outputs information based on the difference in association with the imaging plan. (Supplementary Note 15) The piping inspection device according to any one of Supplements 7 to 14, wherein the imaging condition is an imaging time when the piping is imaged through the transmission, and the processor outputs information based on the difference for each imaging time. (Supplementary Note 16) The piping inspection device according to any one of Supplements 1 to 15, wherein the two opposing side surfaces are side surfaces located at different positions in a circumferential direction of the piping. (Supplementary Note 17) A piping inspection method, wherein a computer acquires first transmission information obtained by image-taking a transmission image of the piping from a first imaging direction in which the two opposing side surfaces are included in a transmission path, and second transmission information obtained by image-taking a transmission image of the piping from a second imaging direction opposite to the first imaging direction, and outputs information based on the difference between the first transmission information and the second transmission information. (Appendix 18) A piping inspection program that causes a computer to acquire first transmission information obtained by transmitting an image of a piping from a first shooting direction in which two opposing sides of the piping are included in the transmission path, and second transmission information obtained by transmitting an image of the piping from a second shooting direction opposite to the first shooting direction, and output information based on the difference between the first transmission information and the second transmission information.

Claims

1. A piping inspection device comprising a processor which acquires first transmission information obtained by photographing a piping from a first shooting direction in which two opposing sides of the piping are included in the transmission path, and second transmission information obtained by photographing the piping from a second shooting direction opposite to the first shooting direction, and outputs information based on the difference between the first transmission information and the second transmission information.

2. The piping inspection device according to claim 1, wherein the processor calculates a statistical value of the difference.

3. The piping inspection device according to claim 2, wherein the processor determines whether or not there is a possibility of an abnormality in the piping based on the magnitude of the statistical value.

4. The piping inspection device according to claim 3, wherein the processor determines whether or not there is a possibility of an abnormality in the piping based on the result of comparing the magnitude of the statistical value with a predetermined threshold value.

5. A piping inspection device as described in claim 3 or 4, wherein the processor determines whether or not there is a possibility of an abnormality in the piping based on an outlier in the magnitude of the statistical value.

6. A piping inspection device as claimed in any one of claims 2 to 5, wherein the processor determines which aspect of the piping may be abnormal based on the positive or negative status of the statistical value.

7. A piping inspection device as described in any one of claims 1 to 6, wherein the processor acquires multiple sets of the first transmission information and the second transmission information when the piping is photographed under different shooting conditions, and outputs information based on the difference for each shooting condition.

8. The piping inspection device according to claim 7, wherein the photographing condition is a photographing position in the piping, and the processor outputs information based on the difference for each of the photographing positions.

9. The piping inspection device according to claim 8, wherein the photographing position is a circumferential position on the piping, and the processor outputs information based on the difference for each circumferential position.

10. A piping inspection device as described in claim 8 or 9, wherein the photographing position is an axial position in the piping, and the processor outputs information based on the difference for each axial position.

11. A piping inspection device described in any one of claims 8 to 10, wherein the processor generates an imaging plan for photographing the piping from different imaging positions, and obtains multiple sets of the first transmission information and the second transmission information when the piping is photographed in accordance with the imaging plan.

12. The piping inspection device according to claim 11, wherein the imaging plan is a plan for photographing the piping at different imaging positions while moving independently in the circumferential direction and the axial direction along the piping.

13. The piping inspection device according to claim 11, wherein the imaging plan is a plan for photographing the piping through different imaging positions while moving in a spiral shape along the piping.

14. A piping inspection device according to any one of claims 11 to 13, wherein the processor outputs information based on the difference in association with the shooting plan.

15. A piping inspection device as described in any one of claims 7 to 14, wherein the shooting condition is the shooting time when the piping is photographed through the optical axis, and the processor outputs information based on the difference for each shooting time.

16. A piping inspection device according to any one of claims 1 to 15, wherein the two opposing side surfaces are side surfaces located at different circumferential positions on the piping.

17. A piping inspection method, in which a computer acquires first transmission information obtained by photographing a piping from a first shooting direction in which two opposing sides of the piping are included in the transmission path, and second transmission information obtained by photographing the piping from a second shooting direction opposite to the first shooting direction, and outputs information based on the difference between the first transmission information and the second transmission information.

18. A piping inspection program which causes a computer to acquire first transmission information obtained by photographing a piping from a first shooting direction in which two opposing sides of the piping are included in the transmission path, and second transmission information obtained by photographing the piping from a second shooting direction opposite to the first shooting direction, and output information based on the difference between the first transmission information and the second transmission information.

Images