Magnetic particle inspection device and magnetic particle inspection method

Abstract

To arrange a magnetizer and a camera in a narrow space inside a tubular member while preventing them from interfering with each other.SOLUTION: A magnetic powder flaw detection device according to an embodiment is inserted into a tubular member, and comprises: an interpolar magnetizer that has a pair of leg parts extended perpendicular to an axial direction of the tubular member and parallel to each other, moves the pair of leg parts in their longitudinal direction so that the leading ends of the pair of leg parts are brought into contact with an inner peripheral surface of the tubular member, and applies a magnetic field; and a camera that picks up an image of a portion to which the magnetic field is applied by the magnetizer on the inner peripheral surface of the tubular member. In the magnetizer, a connection part connecting the bottoms of the pair of leg parts is provided in a U-shape to overhang perpendicular to the longitudinal direction of the pair of leg parts. The camera is arranged between the pair of leg parts such that its outside surface faces the connection part.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a magnetic particle inspection device and a magnetic particle inspection method. [Background technology]

[0002] As disclosed in Patent Document 1, an ultrasonic inspection device is used for inspections such as measuring the wall thickness of tubular members of boilers and detecting internal flaws, etc. In Patent Document 1, an ultrasonic inspection device is inserted into the tubular member, and ultrasonic waves are irradiated onto the tubular member from the ultrasonic inspection device to inspect the tubular member. [Prior art documents] [Patent documents]

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

[0004] The inventor has developed a magnetic particle inspection device that applies a magnetic field to the inner surface of a tubular member and applies a magnetic particle liquid to inspect for flaws. Magnetic particle inspection is also known as MT (Magnetic Particle Testing) or MPI (Magnetic Particle Inspection). Such a magnetic particle inspection device is equipped with a pole-type magnetizer that applies a magnetic field by moving a pair of legs extending parallel to each other in the longitudinal direction and bringing their tips (i.e., magnetic poles) into contact with the inner circumferential surface of the tubular member. The magnetic particle inspection device also includes a camera that captures an image of the area to which the magnetic field is applied by the magnetizer.

[0005] Here, it is difficult to arrange the magnetizer and camera in the narrow space inside the tubular member so that they do not interfere with each other. Other objects and novel features will become apparent from the description of this specification and the accompanying drawings. [Means for solving the problem]

[0006] A magnetic particle inspection device according to one embodiment includes: When inserted into the tubular member, an inter-pole magnetizer having a pair of legs extending perpendicular to the axial direction of the tubular member and parallel to each other, the pair of legs being moved in the longitudinal direction thereof so that the tips of the pair of legs come into contact with the inner circumferential surface of the tubular member to apply a magnetic field; a camera that captures an image of a portion of the inner circumferential surface of the tubular member to which the magnetic field is applied by the magnetizer, In the magnetizer, a connection portion that connects bases of the pair of legs is provided in a U-shape so as to protrude perpendicularly to a longitudinal direction of the pair of legs, The camera is disposed between the pair of legs so that its outer surface faces the connection portion.

[0007] A magnetic particle inspection method according to an embodiment includes: When the magnetic particle detector is inserted into the tubular member, an inter-pole magnetizer having a pair of legs extending perpendicular to the axial direction of the tubular member and parallel to each other, the pair of legs being moved in the longitudinal direction thereof so that the tips of the pair of legs come into contact with the inner circumferential surface of the tubular member to apply a magnetic field; a camera that captures an image of a portion of the inner circumferential surface of the tubular member to which the magnetic field is applied by the magnetizer, In the magnetizer, a connection portion that connects bases of the pair of legs is provided in a U-shape so as to protrude perpendicularly to a longitudinal direction of the pair of legs, The camera is disposed between the pair of legs so that its outer surface faces the connection portion. [Effects of the Invention]

[0008] According to the embodiment, it is possible to provide a magnetic particle flaw detector in which the magnetizer and the camera can be arranged in a narrow space inside a tubular member so as not to interfere with each other. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a side view schematically showing how the inside of a tubular member is inspected using a magnetic particle flaw detector according to a first embodiment. FIG. [Figure 2] 1 is a perspective view schematically showing a magnetic particle flaw detector according to a first embodiment. [Figure 3] 1 is a front view schematically showing a magnetic particle flaw detector according to a first embodiment. [Figure 4] 1 is a side view schematically showing a magnetic particle flaw detector according to a first embodiment. [Figure 5] FIG. 2 is a rear view schematically showing the magnetic particle flaw detector according to the first embodiment. [Figure 6] FIG. 1 is a perspective view of the camera CM. [Figure 7] FIG. 2 is a perspective view showing a linear motion mechanism of the camera CM. [Figure 8] FIG. 10 is a perspective view schematically showing a magnetic particle flaw detector according to a second embodiment. [Figure 9] FIG. 2 is a perspective view showing a linear motion mechanism of the camera CM. DETAILED DESCRIPTION OF THE INVENTION

[0010] 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.

[0011] (First embodiment) An example of the configuration of a magnetic particle inspection device according to the first embodiment will be described with reference to Figs. 1 to 5. Fig. 1 is a side view that schematically shows how the inside of a tubular member is inspected using the magnetic particle inspection device according to the first embodiment. Fig. 2 is a perspective view that schematically shows the magnetic particle inspection device according to the first embodiment. Fig. 3 is a front view that schematically shows the magnetic particle inspection device according to the first embodiment. Fig. 4 is a side view that schematically shows the magnetic particle inspection device according to the first embodiment. Fig. 5 is a rear view that schematically shows the magnetic particle inspection device according to the first embodiment.

[0012] The right-handed xyz Cartesian coordinate system shown in Figure 1 and other drawings is for the convenience of explaining the positional relationships of the components. Normally, the positive z-axis direction is vertically upward, and the xy plane is the horizontal plane, which is common to all drawings.

[0013] <Outline of inspection using magnetic particle testing equipment> First, an overview of inspection using a magnetic particle inspection device 10 according to this embodiment will be described with reference to FIG. 1. FIG. 1 schematically illustrates how the inside of a tubular member is inspected using the magnetic particle inspection device 10 according to this embodiment, and shows a cross-sectional view of the tubular member to be inspected. The tubular member shown in FIG. 1 has a tubular body that is the main body, and a cross-hole that communicates with the inside of the body. Note that the cross-hole is not essential. The tubular member shown in FIG. 1 is not particularly limited, but may be, for example, a reaction vessel for producing low-density polyethylene.

[0014] As shown in FIG. 1, a magnetic particle inspection device 10 is inserted into the body of a tubular member. A magnetic field is applied to the inner circumferential surface of the tubular member, and a magnetic particle liquid is applied to inspect the tubular member. Therefore, the magnetic particle inspection device 10 can detect flaws formed on the inner circumferential surface of the body of the tubular member or on the end of a cross hole, for example. Note that the magnetic particle liquid is applied to the inner circumferential surface of the tubular member from the magnetic particle inspection device 10 after the magnetic field is applied to the inner circumferential surface of the tubular member. Although not shown, for example, the magnetic particle liquid is sprayed onto the inner circumferential surface of the tubular member from the top of the magnetic particle inspection device 10.

[0015] As will be described in detail later, in Fig. 1, the magnetic particle inspection device 10 can apply a magnetic field to the inner peripheral surface of the body while rotating along the inner peripheral surface of the tubular member. The magnetic particle inspection device 10 is also lifted, for example, by a crane (not shown), and can move up and down (in the z-axis direction). With this configuration, the magnetic particle inspection device 10 can be used to inspect the entire inner peripheral surface of the body of the tubular member.

[0016] In addition, in FIG. 1, the magnetic particle flaw detector 10 may be turned upside down and inserted into the body of the tubular member. In the following, the "inner surface of the body of the tubular member" shown in Figure 1 will be simply referred to as the "inner surface of the tubular member", and the "axial direction of the body of the tubular member" will be simply referred to as the "axial direction of the tubular member", etc.

[0017] <Configuration of magnetic particle testing equipment> Next, the configuration of a magnetic particle inspection device 10 according to this embodiment will be described with reference to Figures 1 to 5. As shown in Figures 1 to 5, the magnetic particle inspection device 10 according to this embodiment includes a main body 11 and a rotation mechanism 12.

[0018] <Configuration of main body 11> First, the main body 11 will be described. As shown in Figures 2 to 5, the main body 11 includes a top plate TP, a bottom plate BP, support columns SC11, SC12, SC21, and SC22, a magnetizer MG, magnetizer support members MS1 and MS2, slide bases SB1 and SB2, linear motion mechanisms LM11 and LM12, a camera CM, a camera holder CH, upper UV light sources UL1 and UL2, and lower UV light sources LL1 and LL2.

[0019] The magnetizer MG is an inter-pole type magnetizer, also called a magna. As shown in, for example, Figures 2 to 4, the magnetizer MG includes a pair of legs LP1 and LP2 and a connection part CP. When inserted into the tubular member, the pair of legs LP1, LP2 extend parallel to each other and perpendicular to the axial direction (z-axis direction) of the tubular member. In the magnetizer MG, the tips of the legs LP1, LP2 form magnetic poles, and the legs LP1, LP2 are moved in their longitudinal direction (x-axis direction) so that the magnetic poles come into contact with the inner circumferential surface of the tubular member to apply a magnetic field.

[0020] Here, as shown in Figure 2, for example, the tips of the legs LP1 and LP2 are made up of a yoke YK, and the tips of the yoke YK (i.e., the tips of the legs LP1 and LP2) have an R-shape so as to concentrate the magnetic flux and not to scratch the inner surface of the tubular member to be measured. In the magnetic particle inspection device 10 according to this embodiment, the pair of legs LP1 and LP2 of the magnetizer MG are arranged to line up along the circumferential direction of the tubular member. Therefore, the magnetic particle inspection device 10 according to this embodiment is suitable for detecting flaws that extend in the axial direction of the tubular member between the tips of the legs LP1 and LP2.

[0021] The connecting portion CP connects the bases of the legs LP1 and LP2. In the magnetizer MG according to this embodiment, the connecting portion CP is U-shaped and protrudes perpendicularly (in the negative z-axis direction) to the longitudinal direction (x-axis direction) of the legs LP1 and LP2. Furthermore, as shown in FIG. 3, for example, a magnetizer cable MC for supplying AC power for generating a magnetic field is connected to the center of the lower side of the connection part CP. In the drawings, the boundary lines between the legs LP1, LP2 and the connecting portion CP, which are shown by dashed lines, are for convenience's sake, and the legs LP1, LP2 and the connecting portion CP are integrally formed.

[0022] 2 to 4, the upper surface (the surface on the positive z-axis direction) of the leg LP1 is fixed to a plate-shaped magnetizer support member MS1 extending in the longitudinal direction (x-axis direction) of the leg LP1. The magnetizer support member MS1 is connected to a slide base SB1 extending in the longitudinal direction of the leg LP1 so as to be slidable in the longitudinal direction of the leg LP1.

[0023] The leading end (x-axis positive end) of the slide base SB1 is fixed to a support column SC11 that connects the top plate TP and the bottom plate BP. The rear end (x-axis negative end) of the slide base SB1 is fixed to a support column SC21 that connects the top plate TP and the bottom plate BP. Note that the support column SC11 is omitted in FIG. 4.

[0024] In this way, the leg LP1 is connected to the supports SC11 and SC21 that constitute the housing of the main body 11 so as to be slidable in the longitudinal direction of the leg LP1. As shown in Fig. 4, the tip of the magnetizer support member MS1 is connected to the tip of the rod of the linear motion mechanism LM11, such as a cylinder, via a joint J1.

[0025] Here, as shown in FIG. 4, the tip end of the rod of the linear motion mechanism LM11 is connected to the joint J1 so as to be rotatable around the y-axis, and the rear end of the main body of the linear motion mechanism LM11 is connected to the support column SC21 so as to be rotatable around the y-axis. With this configuration, the leg LP1 (that is, the magnetizer MG) can slide in the longitudinal direction (x-axis direction) of the leg LP1 as the rod of the linear motion mechanism LM11, which is the drive source, expands and contracts.

[0026] 2, the upper surface (the surface on the positive z-axis direction) of the leg LP2 is fixed to a plate-shaped magnetizer support member MS2 extending in the longitudinal direction (x-axis direction) of the leg LP2. The magnetizer support member MS2 is connected to a slide base SB2 extending in the longitudinal direction of the leg LP2 so as to be slidable in the longitudinal direction of the leg LP2.

[0027] The leading end (x-axis positive end) of the slide base SB2 is fixed to a support column SC12 that connects the top plate TP and the bottom plate BP, and the rear end (x-axis negative end) of the slide base SB2 is fixed to a support column SC22 that connects the top plate TP and the bottom plate BP.

[0028] In this way, the leg LP2 is connected to the supports SC12 and SC22 that constitute the housing of the main body 11 so as to be slidable in the longitudinal direction of the leg LP2. As shown in Fig. 2, the tip of the magnetizer support member MS2 is connected to the tip of the rod of the linear motion mechanism LM12, such as a cylinder, via a joint J2.

[0029] Here, the tip of the rod of the linear motion mechanism LM12 is connected to the joint J2 so as to be rotatable around the y-axis, and the rear end of the main body of the linear motion mechanism LM12 is connected to the support column SC22 so as to be rotatable around the y-axis. With this configuration, the leg LP2 (that is, the magnetizer MG) can slide in the longitudinal direction (x-axis direction) of the leg LP2 as the rod of the linear motion mechanism LM12, which is the drive source, expands and contracts.

[0030] The driving source for sliding the magnetizer MG in the longitudinal direction of the legs LP1 and LP2 may be either one of the linear motion mechanisms LM11 and LM12. However, by attaching the linear motion mechanisms LM11 and LM12 to the legs LP1 and LP2, respectively, the tips (i.e., magnetic poles) of the legs LP1 and LP2 can be reliably brought into contact with the inner circumferential surface of the tubular member.

[0031] The top plate TP is, for example, a disk-shaped member, and is arranged so that when inserted into the tubular member, the main surface is perpendicular to the axial direction (z-axis direction) of the tubular member. The bottom plate BP is a disk-shaped member similar to the top plate TP and is disposed parallel to the top plate TP. The top plate TP and bottom plate BP are fixed to each other by supports SC11, SC12, SC21, and SC22 that extend along the axial direction (z-axis direction) of the tubular member. The top plate TP, bottom plate BP, and supports SC11, SC12, SC21, and SC22 form a housing that supports and houses the magnetizer MG.

[0032] 2 and 3, a white light source WLS is provided extending along the longitudinal direction of the support columns SC11 and SC12 on the front surfaces (the sides facing the positive x-axis direction) of the support columns SC11 and SC12 to which the tips of the slide bases SB1 and SB2 are fixed. The white light source WLS is composed of a plurality of white light-emitting diodes (LEDs: Light-Emitting Diodes) WL arranged in the z-axis direction.

[0033] In the illustrated example, the white light source WLS is composed of seven white light emitting diodes WL, but the number of white light emitting diodes WL can be determined appropriately. Although the illustrated supports SC11, SC12, SC21, and SC22 are rectangular prisms, they may be cylindrical, triangular prisms, or have other shapes. Also, supports SC11 and SC12 are omitted in Figures 4 and 5.

[0034] The camera CM captures an image of the area on the inner circumferential surface of the tubular member to which a magnetic field is applied by the magnetizer MG. The image captured by the camera CM is used to check for scratches on the inner circumferential surface of the tubular member. Here, as shown in Figures 2 and 3, for example, the camera CM is installed extending in the longitudinal direction (x-axis direction) of the pair of legs LP1 and LP2 and is positioned between the pair of legs LP1 and LP2. The outer surface of the camera CM faces the connection part CP of the magnetizer MG, which is U-shaped when viewed in the yz plane.

[0035] Therefore, even if the magnetizer MG moves in the longitudinal direction (x-axis direction) of the pair of legs LP1, LP2, the magnetizer MG and the camera CM do not interfere with each other. In this way, in the magnetic particle flaw detector 10 according to this embodiment, the magnetizer MG and the camera CM can be arranged in the narrow space inside the tubular member so as not to interfere with each other. The camera CM can also move in the longitudinal direction (x-axis direction). The detailed configuration of the camera CM will be described later.

[0036] The upper UV light sources UL1 and UL2 and the lower UV light sources LL1 and LL2 are ultraviolet (UV) light sources for irradiating ultraviolet light onto a portion of the inner circumferential surface of the tubular member to which a magnetic field is applied by the magnetizer MG. For example, the upper UV light sources UL1 and UL2 have a power of 1000 μW / cm 2 Magnetic particle testing is performed at the above ultraviolet intensity.

[0037] 2 and 3, the upper UV light sources UL1 and UL2 and the lower UV light sources LL1 and LL2 are arranged opposite each other via legs LP1 and LP2 of the magnetizer MG. In the illustrated example, the upper UV light sources UL1 and UL2 are fixed to the top plate TP, and the lower UV light sources LL1 and LL2 are fixed to the bottom plate BP.

[0038] Here, the four light sources, the upper UV light sources UL1 and UL2 and the lower UV light sources LL1 and LL2, can be turned on / off independently. For example, if halation occurs in an image captured by the camera CM due to one of the upper UV light sources UL1 and UL2 or the lower UV light sources LL1 and LL2, only the light source causing the halation can be switched from on to off. The upper UV light source and the lower UV light source may each be provided in a single number, or three or more of them may be provided.

[0039] As described above, in the magnetic particle flaw detector 10 according to this embodiment, the magnetizer MG has a connecting portion CP that connects the bases of the pair of legs LP1, LP2 and is provided in a U-shape so as to extend perpendicularly to the longitudinal direction of the pair of legs LP1, LP2. The camera CM is disposed between the pair of legs LP1, LP2 so that its outer surface faces the connecting portion CP.

[0040] Therefore, even if the magnetizer MG moves in the longitudinal direction (x-axis direction) of the pair of legs LP1, LP2, the magnetizer MG and the camera CM do not interfere with each other. In this way, in the magnetic particle flaw detector 10 according to this embodiment, the magnetizer MG and the camera CM can be arranged in the narrow space inside the tubular member so as not to interfere with each other.

[0041] <Detailed structure of camera commercials> Here, the detailed configuration of the camera CM will be described with reference to Figures 6 and 7. Figure 6 is a perspective view of the camera CM. Figure 7 is a perspective view showing the linear motion mechanism of the camera CM. 6, the camera CM includes a camera body CMB and a camera case CC. The camera case CC is a cylindrical housing that covers the camera body CMB and accommodates it in a waterproof manner.

[0042] An air inlet AI is provided at one end (the end on the positive x-axis side) of the camera case CC for introducing air into the interior of the camera case CC. On the other hand, an air outlet AO is provided at the other end (the end on the negative x-axis side) of the camera case CC for discharging air from the interior of the camera case CC. For example, by constantly flowing air into the interior of the camera case CC, fogging of the lens of the camera body CMB can be suppressed. Also, heat generated by the camera body CMB can be dissipated.

[0043] 6, the camera CM is supported by a camera holder CH. More specifically, the camera holder CH is a plate-like member shaped like a home base when viewed in the yz plane. The camera CM (i.e., the camera case CC) is inserted into a through-hole provided in the center of the camera holder CH, and the camera CM is fixed to the camera holder CH. A pair of linear sliders LS are fixed to both end surfaces of the camera holder CH in the width direction (y-axis direction).

[0044] 7, a pair of linear sliders LS fixed to a camera holder CH slides in the x-axis direction along a pair of guide rails GR1 and GR2 extending in the longitudinal direction (x-axis direction) of the camera CM. The pair of guide rails GR1 and GR2 are fixed to supports SC21 and SC22, respectively. In other words, the camera CM is slidably supported on the guide rails GR1 and GR2 via the camera holder CH and the linear slider LS.

[0045] 7, the linear motion mechanism for moving the camera CM in the x-axis direction is a motor-driven ball screw mechanism, and includes a screw shaft SF, a nut NT, a shaft gear SG, a shaft support member SS, a bearing BR, a motor MT1, a motor holder MH, and a motor gear MG1.

[0046] The screw shaft SF is disposed above the camera CM and extends in the x-axis direction parallel to the camera CM. The rear end (the end on the x-axis negative side) of the screw shaft SF is rotatably supported by a shaft support member SS via a bearing BR. Both ends of the shaft support member SS are fixed to support columns SC21 and SC22, respectively. A shaft gear SG is fixed to the tip (the end on the x-axis positive side) of the screw shaft SF.

[0047] The screw shaft SF is rotationally driven by a motor MT1. More specifically, the motor MT1 is disposed above the screw shaft SF, with its rotational shaft extending parallel to the screw shaft SF. The motor MT1 is fixed to the supports SC21 and SC22 via a motor holder MH. A motor gear MG1 that meshes with a shaft gear SG is fixed to the tip (the end on the positive x-axis direction side) of the rotational shaft of the motor MT1. Therefore, the rotation of the motor gear MG1 fixed to the rotational shaft of the motor MT1 is transmitted to the screw shaft SF via the shaft gear SG. With this configuration, the screw shaft SF is rotationally driven by the motor MT1.

[0048] As shown in Fig. 7, a nut NT is threaded onto the screw shaft SF, and when the screw shaft SF is rotated, the nut NT moves in the x-axis direction. Here, the screw shaft SF is inserted into a through-hole provided in the upper end of the camera holder CH shown in Fig. 6, and the nut NT is fixed to the upper end of the camera holder CH as shown in Fig. 7. Therefore, when the nut NT moves in the x-axis direction, the camera holder CH and the camera CM also move in the x-axis direction.

[0049] With this configuration, the camera CM can move in the longitudinal direction (x-axis direction) of the legs LP1 and LP2 of the magnetizer MG independently of the magnetizer MG. For example, if a flaw is detected in a location to which a magnetic field is applied by the magnetizer MG, the camera CM can approach the flaw and capture an image of the flaw. Although not shown, a camera cable for transmitting and receiving signals is connected to the camera CM.

[0050] <Configuration of rotation mechanism 12> Next, the rotation mechanism 12 will be described. The rotation mechanism 12 is provided on the lower end side of the main body 11 and rotates the magnetic particle flaw detector 10 in the circumferential direction of the tubular member when inserted inside the tubular member. The rotation mechanism 12 allows the magnetic particle flaw detector 10 to apply a magnetic field to the inner circumferential surface of the body while rotating along the inner circumferential surface of the tubular member. The rotation mechanism 12 may be provided on the upper end side of the main body 11 when inserted inside the tubular member, or may be provided on both the upper end side and the lower end side of the main body 11.

[0051] For example, as shown in Figures 2 and 5, the rotation mechanism 12 includes wheels W11, W12, W21, and W22, wheel holders WH1 and WH2, a linear motion mechanism LM2, a motor MT2, a motor gear MG2, transmission gears TG1 and TG2, axle gears WG1 and WG2, and omni-wheels OW1 and OW2.

[0052] The wheels W11 and W12 are non-driven wheels that are slidable in the radial direction (x-axis direction) of the tubular member when inserted inside the tubular member. The axles of the wheels W11 and W12 are parallel to the axial direction (z-axis direction) of the tubular member, and both ends of the axles are rotatably supported by the wheel holder WH1.

[0053] When inserted into the tubular member, the wheels W11 and W12 are provided at the other radial end (x-axis positive end) of the tubular member. In contrast, the wheels W21 and W22 are provided at one radial end (x-axis negative end) of the tubular member. In other words, the wheels W11 and W12 are disposed opposite the wheels W21 and W22 across the axis of the tubular member.

[0054] The wheels W11 and W12 can slide in the radial direction (x-axis direction) of the tubular member by a linear motion mechanism LM2 such as a cylinder. For example, as shown in Fig. 4, the linear motion mechanism LM2 is fixed to the lower surface of the bottom plate BP of the main body 11 so that when inserted into the tubular member, it extends in the radial direction (x-axis direction) of the tubular member. A wheel holder WH1 is fixed to the tip (end on the positive x-axis direction) of the linear motion mechanism LM2.

[0055] The wheels W21 and W22 are drive wheels that are provided so as to be able to come into contact with the inner circumferential surface of the tubular member when inserted inside the tubular member. The axles of the wheels W21 and W22 are parallel to the axial direction (z-axis direction) of the tubular member, and both ends of the axles are rotatably supported by wheel holders WH2. Although not shown, the wheel holder WH2 is also fixed to the underside of the bottom plate BP of the main body 11. In other words, the wheels W21 and W22 are fixed to the bottom plate BP of the main body 11 via the wheel holders WH2.

[0056] The wheels W21 and W22 are driven by a motor MT2, which is a drive source that drives the wheels W21 and W22. 4, when the motor MT2 is inserted into the tubular member, it extends in the radial direction of the tubular member. A motor gear MG2 is fixed to the rotating shaft of the motor MT2, and rotates as the rotating shaft of the motor MT2 rotates.

[0057] 5, the motor gear MG2 meshes with the transmission gear TG1, and the transmission gear TG2 is fixed to the rotation shaft of the transmission gear TG1, and the transmission gear TG2 meshes with the axle gears WG1 and WG2. Therefore, the rotation of the motor gear MG2 is transmitted to the axle gears WG1 and WG2 via the transmission gears TG1 and TG2. The axle gear WG1 is fixed to the upper end of the axle of the wheel W21. Similarly, the axle gear WG2 is fixed to the upper end of the axle of the wheel W22.

[0058] In this way, the rotation of the motor gear MG2 fixed to the rotation shaft of the motor MT2 is transmitted via the transmission gears TG1 and TG2 to the axle gears WG1 and WG2 fixed to the axles of the wheels W21 and W22. With this configuration, the wheels W21 and W22 are rotated by the motor MT2.

[0059] When the magnetic particle inspection device 10 rotates in the circumferential direction of the tubular member, for example, in FIG. 2, the wheels W11 and W12 move radially outward (toward the positive x-axis direction) of the tubular member and are pressed against the inner circumferential surface of the tubular member. At that time, the wheels W21 and W22 are also pressed against the inner circumferential surface of the tubular member. In this state, when the wheels W21 and W22 are driven by the motor MT2, the wheels W11, W12, W21, and W22 run in the circumferential direction on the inner circumferential surface of the tubular member. As a result, the magnetic particle inspection device 10 rotates in the circumferential direction of the tubular member.

[0060] On the other hand, when the magnetic particle inspection device 10 moves in the axial direction (z-axis direction) of the tubular member, the wheels W11 and W12 move radially inward (toward the negative x-axis) of the tubular member so as not to come into contact with the inner circumferential surface of the tubular member. Here, if the wheels W11 and W12 do not come into contact with the inner circumferential surface of the tubular member, the wheels W21 and W22 also do not come into contact with the inner circumferential surface of the tubular member. Therefore, the magnetic particle inspection device 10 can move in the axial direction (z-axis direction) of the tubular member.

[0061] The omni-wheels OW1 and OW2 are wheels that can move in any direction and are provided on the peripheral edge of the bottom plate BP of the main body 11. More specifically, the omni-wheels OW1 and OW2 are provided on both ends of the bottom plate BP in the y-axis direction. When the magnetic particle flaw detector 10 moves in the axial direction of the tubular member (z-axis direction), the omni-wheels OW1 and OW2 prevent the outer edge of the bottom plate BP from colliding with the inner peripheral surface of the tubular member, thereby preventing scratches from being generated on the inner peripheral surface of the tubular member.

[0062] In the illustrated example, two drive wheels (wheels W21 and W22) are provided, but the number of drive wheels may be one or three or more. The drive wheels W21 and W22 may also be slidable in the radial direction (x-axis direction) of the tubular member, similar to the wheels W11 and W12. In addition, in the illustrated example, two non-driven wheels (wheels W11 and W12) are provided, but the number of non-driven wheels may be one, or three or more. Furthermore, the wheels W11 and W12 may be drive wheels. Moreover, the omni-wheel may also be provided on the peripheral edge of the top plate TP of the main body 11.

[0063] (Second embodiment) Next, an example of the configuration of a magnetic particle inspection device according to the second embodiment will be described with reference to Fig. 8 and Fig. 9. Fig. 8 is a perspective view that schematically shows the magnetic particle inspection device according to the second embodiment. Fig. 9 is a perspective view that shows a linear motion mechanism of a camera CM. Fig. 8 shows only the main body 21 of the magnetic particle inspection device 20 according to this embodiment. The rotation mechanism of the magnetic particle inspection device 20 according to this embodiment is the same as the rotation mechanism 12 of the magnetic particle inspection device 10 according to the first embodiment. Furthermore, the top plate TP and the bottom plate BP are omitted from Fig. 8.

[0064] 2, in the magnetic particle flaw detector 10 according to the first embodiment, a pair of legs LP1 and LP2 of the magnetizer MG are arranged to align along the circumferential direction of the tubular member. Therefore, the magnetic particle flaw detector 10 according to the first embodiment is suitable for detecting flaws extending in the axial direction of the tubular member between the tips of the legs LP1 and LP2.

[0065] 8, in the magnetic particle inspection device 20 according to this embodiment, the pair of legs LP1 and LP2 of the magnetizer MG are arranged to align along the axial direction (z-axis direction) of the tubular member. Therefore, the magnetic particle inspection device 20 according to this embodiment is suitable for detecting flaws extending in the circumferential direction of the tubular member between the tips of the legs LP1 and LP2.

[0066] Therefore, magnetic particle inspection may be performed using the magnetic particle inspection device (first magnetic particle inspection device) 10 according to the first embodiment and the magnetic particle inspection device (second magnetic particle inspection device) 20 according to this embodiment. That is, magnetic particle inspection may be performed using one of the magnetic particle inspection devices according to the first and second embodiments, and then magnetic particle inspection may be performed using the other of the magnetic particle inspection devices according to the first and second embodiments. By using both magnetic particle inspection devices, flaws formed on the inner circumferential surface of a tubular member, etc., can be detected more accurately than when only one magnetic particle inspection device is used.

[0067] In the magnetizer MG of this embodiment, the connection portion CP that connects the bases of the legs LP1 and LP2 is U-shaped and extends perpendicularly (in the negative y-axis direction) to the longitudinal direction (x-axis direction) of the legs LP1 and LP2. That is, the magnetizer MG according to this embodiment is arranged so that the magnetizer MG according to the first embodiment shown in FIG. 2 is rotated 90 degrees clockwise when viewed from the positive x-axis direction. As shown in FIG. 8, in the magnetizer MG according to this embodiment, a magnetizer cable MC for supplying AC power for generating a magnetic field is connected to the upper end of the connection part CP.

[0068] 8, the side surface of the leg LP1 on the positive y-axis direction is fixed to a plate-shaped magnetizer support member MS1 extending in the longitudinal direction (x-axis direction) of the leg LP1. The magnetizer support member MS1 is connected to a slide base SB1 extending in the longitudinal direction of the leg LP1 so as to be slidable in the longitudinal direction of the leg LP1.

[0069] The front end (x-axis positive side end) of slide base SB1 is fixed to cross beam CB11 that connects the lower ends of columns SC11 and SC12. The rear end (x-axis negative side end) of slide base SB1 is fixed to the lower end of column SC22.

[0070] In this way, the leg LP1 is connected to the cross beam CB11 and the support column SC22 that constitute the housing of the main body 11 so as to be slidable in the longitudinal direction of the leg LP1. As shown in Fig. 8, the tip of the magnetizer support member MS1 is connected to the tip of the rod of the linear motion mechanism LM11, such as a cylinder, via a joint J1.

[0071] Here, the tip of the rod of the linear motion mechanism LM11 is connected to the joint J1 so as to be rotatable around the y-axis, and the rear end of the main body of the linear motion mechanism LM11 is connected to the lower end of the support column SC22 so as to be rotatable around the y-axis. With this configuration, the leg LP1 (that is, the magnetizer MG) can slide in the longitudinal direction (x-axis direction) of the leg LP1 as the rod of the linear motion mechanism LM11, which is the drive source, expands and contracts.

[0072] As with the leg LP1, the side surface of the leg LP2 on the positive y-axis direction is fixed to a plate-shaped magnetizer support member MS2 extending in the longitudinal direction (x-axis direction) of the leg LP2, as shown in Fig. 8. The magnetizer support member MS2 is connected to a slide base SB2 extending in the longitudinal direction of the leg LP2 so as to be slidable in the longitudinal direction of the leg LP2.

[0073] The front end (x-axis positive side end) of slide base SB2 is fixed to cross beam CB12 that connects the upper ends of columns SC11 and SC12. The rear end (x-axis negative side end) of slide base SB2 is fixed to the upper end of column SC22.

[0074] In this way, the leg LP2 is connected to the cross beam CB12 and the support column SC22, which constitute the housing of the main body 11, so as to be slidable in the longitudinal direction of the leg LP2. As shown in Fig. 8, the tip of the magnetizer support member MS2 is connected to the tip of the rod of the linear motion mechanism LM12, such as a cylinder, via a joint J2.

[0075] Here, the tip of the rod of the linear motion mechanism LM12 is connected to the joint J2 so as to be rotatable around the y-axis, and the rear end of the main body of the linear motion mechanism LM12 is connected to the upper end of the support column SC22 so as to be rotatable around the y-axis. With this configuration, the leg LP2 (that is, the magnetizer MG) can slide in the longitudinal direction (x-axis direction) of the leg LP2 as the rod of the linear motion mechanism LM12, which is the drive source, expands and contracts.

[0076] Similar to the magnetic particle flaw detector 10 according to the first embodiment shown in Figure 2 etc., the top plate TP and bottom plate BP (not shown in Figure 8) are connected to each other by supports SC11, SC12, SC21, and SC22 extending along the axial direction (z-axis direction) of the tubular member.

[0077] On the other hand, in the magnetic particle flaw detector 20 according to this embodiment, as shown in Fig. 8, the lower ends of the supports SC11 and SC12 are connected to each other by a cross beam CB11 extending in the y-axis direction. Also, the upper ends of the supports SC11 and SC12 are connected to each other by a cross beam CB12 extending in the y-axis direction.

[0078] 9, the pillars SC21 and SC22 are connected by a pair of cross beams CB21 and CB22 that extend in the y-axis direction and are arranged opposite each other across the camera CM. The top plate TP, the bottom plate BP, the pillars SC11, SC12, SC21, and SC22, and the cross beams CB11, CB12, CB21, and CB22 form a housing that supports and houses the magnetizer MG.

[0079] 8, in the magnetic particle flaw detector 20 according to this embodiment, a camera CM extending in the longitudinal direction (x-axis direction) of the pair of legs LP1 and LP2 is also disposed between the pair of legs LP1 and LP2. The outer surface of the camera CM faces the connection part CP of the magnetizer MG, which is U-shaped when viewed in the yz plane.

[0080] Therefore, even if the magnetizer MG moves in the longitudinal direction (x-axis direction) of the pair of legs LP1, LP2, the magnetizer MG and the camera CM do not interfere with each other. In this way, in the magnetic particle flaw detector 20 according to this embodiment, the magnetizer MG and the camera CM can also be arranged in the narrow space inside the tubular member so as not to interfere with each other.

[0081] The detailed configuration of the camera CM is similar to that of the magnetic particle flaw detector 10 according to the first embodiment, and is shown in FIG. 9, a pair of linear sliders LS fixed to the camera holder CH slides in the x-axis direction along a pair of guide rails GR1 and GR2 extending in the longitudinal direction (x-axis direction) of the camera CM. The pair of guide rails GR1 and GR2 are fixed to cross beams CB21 and CB22, respectively. In other words, the camera CM is slidably supported on the guide rails GR1 and GR2 via the camera holder CH and the linear slider LS.

[0082] 9, the linear motion mechanism for moving the camera CM in the x-axis direction is a motor-driven ball screw mechanism, and includes a screw shaft SF, a nut NT, a shaft gear SG, a shaft support member SS, a bearing BR, a motor MT1, a motor holder MH, and a motor gear MG1. The screw shaft SF is provided on the positive y-axis side of the camera CM, extending in the x-axis direction parallel to the camera CM.

[0083] As shown in Fig. 9, the rear end (x-axis negative side end) of the screw shaft SF is rotatably supported by a shaft support member SS via a bearing BR. The lower end of the shaft support member SS is fixed to the upper end of support column SC22a, and the upper end of the shaft support member SS is fixed to the lower end of support column SC22b. In other words, support column SC22 is divided into support columns SC22a and SC22b, which are connected by the shaft support member SS. A shaft gear SG is fixed to the tip end (x-axis positive side end) of the screw shaft SF.

[0084] The screw shaft SF is rotationally driven by a motor MT1. More specifically, as shown in FIG. 9, a motor MT1 is disposed on the y-axis positive side of the screw shaft SF, with its rotational shaft extending parallel to the screw shaft SF. The motor MT1 is fixed to the supports SC22a and SC22b (i.e., the support SC22) via a motor holder MH. A motor gear MG1 that meshes with a shaft gear SG is fixed to the tip (the end on the x-axis positive side) of the rotational shaft of the motor MT1. Therefore, the rotation of the motor gear MG1 fixed to the rotational shaft of the motor MT1 is transmitted to the screw shaft SF via the shaft gear SG. With this configuration, the screw shaft SF is rotationally driven by the motor MT1.

[0085] As shown in Fig. 9, a nut NT is threaded onto the screw shaft SF, and when the screw shaft SF is rotated, the nut NT moves in the x-axis direction. Here, the screw shaft SF is inserted into a through-hole provided in the upper end of the camera holder CH shown in Fig. 6, and the nut NT is fixed to the upper end of the camera holder CH as shown in Fig. 9. Therefore, when the nut NT moves in the x-axis direction, the camera holder CH and the camera CM also move in the x-axis direction.

[0086] With this configuration, the camera CM can move in the longitudinal direction (x-axis direction) of the legs LP1 and LP2 of the magnetizer MG independently of the magnetizer MG. For example, if a flaw is detected in a location to which a magnetic field is applied by the magnetizer MG, the camera CM can approach the flaw and capture an image of the flaw.

[0087] Although not shown, the magnetic particle flaw detector 20 according to this embodiment also includes two pairs of ultraviolet light sources (corresponding to the upper UV light sources UL1, UL2 and the lower UV light sources LL1, LL2 shown in FIG. 2, etc.) arranged opposite each other via a pair of legs LP1, LP2. The other configurations are the same as those of the magnetic particle flaw detector 10 according to the first embodiment, and therefore the description thereof will be omitted.

[0088] 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]

[0089] 10, 20 Magnetic particle flaw detection equipment 11, 21 Main body 12 Rotation mechanism AI air inlet AO air outlet BP bottom plate BR bearing CB11, CB12, CB21, CB22 Cross beam CC Camera Case CH Camera Holder Commercial camera CMB camera body CP connection GR1, GR2 guide rails J1, J2 joints LL1, LL2 Lower UV light source LM11, LM12, LM2 linear motion mechanism LP1, LP2 legs LS Linear Slider MG magnetizer MG1, MG2 motor gear MH motor holder MS1, MS2 magnetizer support members MT1, MT2 motors NT Nut OW1, OW2 Omniwheel SB1, SB2 slide base SC11, SC12, SC21, SC22, SC22a, SC22b struts SF screw shaft SG shaft gear SS shaft support member TG1, TG2 transmission gear TP top plate UL1, UL2 Upper UV light source W11, W12, W21, W22 wheels WG1, WG2 axle gear WH1, WH2 wheel holder WL White Light Emitting Diode WLS white light source YK York

Claims

1. A magnetic particle flaw detection device that is inserted into a tubular member and inspects the inner circumferential surface of the tubular member by applying a magnetic field to the inner circumferential surface and applying a magnetic particle liquid to the inner circumferential surface, When inserted into the tubular member, an inter-pole magnetizer having a pair of legs extending perpendicular to the axial direction of the tubular member and parallel to each other, the pair of legs being moved in the longitudinal direction so that the tips of the pair of legs come into contact with the inner circumferential surface of the tubular member to apply the magnetic field; a camera that captures an image of a portion of the inner circumferential surface of the tubular member to which the magnetic field is applied by the magnetizer; a rotation mechanism provided on one end side of the axial direction of the tubular member and rotating the magnetic particle flaw detection device in the circumferential direction of the tubular member, In the magnetizer, a connection portion that connects bases of the pair of legs is provided in a U-shape so as to protrude perpendicularly to a longitudinal direction of the pair of legs, the camera is disposed between the pair of legs such that an outer surface of the camera faces the connection portion; When the magnetic field generating device is inserted into the tubular member, the magnetic field generating device rotates the tubular member in a circumferential direction thereof by the rotation mechanism while applying a magnetic field to the inner circumferential surface of the tubular member. Magnetic particle flaw detection equipment.

2. When inserted into the tubular member, The pair of legs are arranged to be aligned along the axial direction of the tubular member. The magnetic particle inspection device according to claim 1.

3. When inserted into the tubular member, The pair of legs are arranged to be aligned along the circumferential direction of the tubular member. The magnetic particle inspection device according to claim 1.

4. the device further includes a pair of ultraviolet light sources that irradiate ultraviolet light onto a portion of the inner circumferential surface of the tubular member to which the magnetic field is applied by the magnetizer, and that are arranged opposite to each other across the pair of legs. The magnetic particle inspection device according to any one of claims 1 to 3.

5. the device further includes a plurality of pairs of ultraviolet light sources that irradiate ultraviolet light onto a portion of the inner circumferential surface of the tubular member to which the magnetic field is applied by the magnetizer, and that are arranged opposite to each other via the pair of legs. The magnetic particle inspection device according to any one of claims 1 to 3.

6. The rotation mechanism includes: a drive wheel having an axle parallel to the axial direction of the tubular member and capable of contacting the inner circumferential surface of the tubular member; a drive source that drives the drive wheels; a wheel whose axle is parallel to the axial direction of the tubular member and is disposed opposite the drive wheel across the axis of the tubular member; The magnetic particle inspection device according to claim 1.

7. The rotation mechanism includes: The vehicle further includes a linear motion mechanism that slides the wheels in the radial direction of the tubular member. The magnetic particle inspection device according to claim 6.

8. The vehicle includes a plurality of at least one of the drive wheels and the wheels, The magnetic particle inspection device according to claim 6 or 7.

9. The camera is The camera body and and a housing that accommodates the camera body in a waterproof manner. The magnetic particle inspection device according to any one of claims 1 to 3.

10. the camera is movable in the longitudinal direction of the pair of legs independently of the pair of legs; The magnetic particle inspection device according to any one of claims 1 to 3.

11. a pair of white light sources each extending in the axial direction of the tubular member and arranged opposite to each other with the pair of legs interposed therebetween; The magnetic particle inspection device according to any one of claims 1 to 3.

12. (a) inserting a magnetic particle inspection device into a tubular member; (b) applying a magnetic field to the inner circumferential surface of the tubular member by the magnetic particle inspection device and applying a magnetic particle liquid to the inner circumferential surface of the tubular member, The magnetic particle flaw detector is When inserted into the tubular member, an inter-pole magnetizer having a pair of legs extending perpendicular to the axial direction of the tubular member and parallel to each other, the pair of legs being moved in the longitudinal direction so that the tips of the pair of legs come into contact with the inner circumferential surface of the tubular member to apply the magnetic field; a camera that captures an image of a portion of the inner circumferential surface of the tubular member to which the magnetic field is applied by the magnetizer; a rotation mechanism provided on one end side of the axial direction of the tubular member and rotating the magnetic particle flaw detection device in the circumferential direction of the tubular member, In the magnetizer, a connection portion that connects bases of the pair of legs is provided in a U-shape so as to protrude perpendicularly to a longitudinal direction of the pair of legs, the camera is disposed between the pair of legs such that an outer surface of the camera faces the connection portion; When the magnetic field generating device is inserted into the tubular member, the magnetic field generating device rotates the tubular member in a circumferential direction thereof by the rotation mechanism while applying a magnetic field to the inner circumferential surface of the tubular member. Magnetic particle flaw detection method.

13. (a) inserting a magnetic particle inspection device into a tubular member; (b) applying a magnetic field to the inner circumferential surface of the tubular member by the magnetic particle inspection device and applying a magnetic particle liquid to the inner circumferential surface of the tubular member, The magnetic particle flaw detector is When inserted into the tubular member, an inter-pole magnetizer having a pair of legs extending perpendicular to the axial direction of the tubular member and parallel to each other, the pair of legs being moved in the longitudinal direction so that the tips of the pair of legs come into contact with the inner circumferential surface of the tubular member to apply the magnetic field; a camera that captures an image of a portion of the inner circumferential surface of the tubular member to which the magnetic field is applied by the magnetizer, In the magnetizer, a connection portion that connects bases of the pair of legs is provided in a U-shape so as to protrude perpendicularly to a longitudinal direction of the pair of legs, the camera is disposed between the pair of legs such that an outer surface of the camera faces the connection portion; The magnetic particle flaw detector is a first magnetic particle flaw detection device that, when inserted into the tubular member, the pair of legs are arranged to be aligned along the axial direction of the tubular member; a second magnetic particle inspection device that is arranged so that the pair of legs are aligned along the circumferential direction of the tubular member when inserted into the tubular member, After performing the steps (a) and (b) using one of the first and second magnetic particle flaw detectors, The steps (a) and (b) are performed using the other of the first and second magnetic particle flaw detection devices. Magnetic particle flaw detection method.

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