JP5127313B2 - Inspection system - Google Patents

Description

  The present invention relates to an inspection system for inspecting defects such as cracks in the walls of various facilities and equipment such as nuclear power plants, thermal power plants, and the like, for example, reactor vessels, in-reactor structures, and piping. .

  As shown in FIG. 11, in a periodic inspection such as an inner wall surface of a nuclear reactor vessel 41 such as a nuclear power plant, an outer wall surface of a reactor internal structure 43 that supports a core 42, and an inner wall surface of a pipe 43 from the reactor vessel 41. A CCD camera or the like (not shown) is inserted, and visual inspection is performed by remote control using a control computer. When a part of a suspicious defect such as stress corrosion cracking (SCC) is detected in the object to be inspected by this remote visual inspection, a material inspection is performed in order to inspect further in detail. In this material inspection, an suspicious spot is irradiated with an electron beam and characteristic X-rays generated from the spot are used. However, at present, there is a demand for an inspection system that can perform material inspection more efficiently from the inside of the reactor vessel 41 and the inside of the piping 43 compared to the conventional inspection system.

  On the other hand, for example, as shown in an enlarged view of a portion surrounded by a circle A in FIG. 11, as an example of an inspection of whether or not there is a crack or the like in the welded portion 49, for example, The sound wave B is irradiated, and a crack or the like of the weld 49 is inspected by the reflected wave C. However, in this inspection, if there is a weld back wave 51 in the welded portion 49 and there is a reflected wave C due to the weld back wave 51, the reflected wave C from the defect or the reflected wave from the weld back wave 51 It is pointed out that judgment of C is difficult. Therefore, there is a demand for an inspection system that can perform an accurate X-ray inspection on such a welded portion 49 and the like with respect to a conventional inspection system.

An inspection apparatus for this nuclear reactor or the like is proposed in, for example, Japanese Patent Application Laid-Open No. 08-211022. In addition, an inspection apparatus that causes a self-propelled robot to self-travel to an inspection target position in accordance with a remote operation command, irradiates the inspection target with X-rays, and detects X-rays transmitted through the inspection target is disclosed in, for example, Japanese Patent Application Laid-Open No. 2004-053475 Proposed in
Japanese Patent Application Laid-Open No. 08-211022 JP 2004-053475 A

  In the present invention, first, when there is a defect on the inner wall surface of the reactor vessel, the outer wall surface of the reactor internal structure, the inner wall surface of the piping, etc., the material structure can be efficiently inspected. Secondly, it should be possible to solve from the inside of the reactor vessel and the piping, for example, that X-ray inspection such as whether there is a defect in the welded part or the like or whether it is a welding back wave can be performed with higher accuracy. It is an issue.

  The inspection system according to the first aspect of the present invention includes an inspection set mounted on a transfer robot and capable of movement control, and a control computer that controls the operation of the inspection set from a remote position. The inspection set includes an electric field as a radiation source. A radiation-type electron emitter and an X-ray detector are provided, and the inspection set can be controlled to be sealed in the same vacuum space together with the inspection object by a sealing device at the time of inspection.

  The field emission electron emitter is preferably a cathode surface provided with a nanocarbon film that emits an electron beam as radiation by field emission.

  The nano-carbon film has fine nanometer-order projections such as carbon nanotubes, carbon nanowalls, carbon nanofibers, diamond-like carbon, amorphous diamond, crystalline diamond, graphite, fullerene, and acicular carbon film. It is a carbon film that can emit an electron beam from the protrusion by emitting an electric field by applying an electric field.

  In the first aspect of the present invention, since the radiation source is composed of a field emission type electron emitter that emits electron beams from the nanocarbon film by field emission at high density, the X-ray intensity generated from the inspection object can be increased, and inspection can be performed. The device can be downsized, and the inspection device is controlled by the control computer even if the location of the inspection object is a narrow internal space such as a reactor vessel or piping and where entry of workers is difficult The inspection can be performed at the position to be inspected and the radiation source is a field emission type, so that the inspection apparatus can be set at the position to be inspected and the electron beam can be irradiated immediately after the power is turned on. It can be implemented quickly and efficiently.

  An inspection system according to the second aspect of the present invention includes an inspection set mounted on a transfer robot and capable of movement control, and a control computer for controlling the operation of the inspection set from a remote position. An anode tip extending in a conical shape on the line of irradiation direction, a field emission type annular electron emitter surrounding the anode tip in an annular shape, and an electron disposed at least at the rear side in the X-ray irradiation direction with respect to the annular electron emitter And an X-ray derivation window made of a thin film capable of transmitting X-rays on the tube wall of the vacuum tube in front of the anode tip.

  In the second aspect of the present invention, an inspection set is arranged inside a pipe or the like, X-rays are irradiated to the inspection object, X-rays transmitted through the inspection object are irradiated to an X-ray film or the like outside the pipe, and the like. Since the state of the welded portion can be inspected by X-ray, it is possible to accurately perform the inspection judgment of the weld back wave protruding from the inner wall surface of the pipe or the like, which is considered difficult in the ultrasonic flaw detection inspection, and the welded portion defect. In the second aspect of the present invention, since X-rays can be emitted in a beam form from the tip of the anode in a high density, the incident X-ray intensity to the X-ray imaging apparatus including the X-ray film disposed on the back of the inspection object is increased. As a result, the inspection set can be reduced in size, so that it can be easily set in a narrow space such as a pipe. Furthermore, since the electron emitter is a field emission type, the inspection apparatus is placed at the inspection target position. It is possible to emit electrons from the annular cathode immediately after setting and power-on, and to irradiate X-rays from the tip of the anode toward the inspection object, so that inspection can be performed quickly and efficiently.

  In a preferred embodiment of the present invention, the annular electron emitter is provided with a nanocarbon film that emits an electron beam as radiation by field emission on the annular cathode surface.

  One preferable aspect of the present invention is to provide a heat conducting part at the rear part of the anode tip part.

  One preferable aspect of the present invention is that the electron shielding member is annularly arranged around the X-ray irradiation direction.

  One preferable aspect of the present invention is that the electron shielding member has an annular plate structure having an inner diameter smaller than the inner diameter of the annular electron emitter.

  In a preferred aspect of the present invention, the electron shielding member includes a pair of annular electron emitters that are arranged on both sides in the X-ray irradiation direction of the annular electron emitter in an annular shape and have an inner diameter smaller than the inner diameter of the annular electron emitter. It is having a board part.

  In a preferred aspect of the present invention, the annular electron emitter and the electron shielding member are movable forward and backward in the X-ray irradiation direction with respect to the anode tip, and the X-ray flux emitted from the anode tip by the movement. This means that the bundle diameter can be controlled.

  One preferable aspect of the present invention is that the inspection set is covered with a sealing device in the same space together with the inspection target, and drainage and atmospheric pressure of the internal space of the sealing device can be controlled.

  One preferable aspect of the present invention is to transmit the X-rays radiated from the tip of the anode through the inspection object and detect the transmitted X-rays (transmitted X-rays).

  One preferable aspect of the present invention is to detect X-rays reflected from the inspection object (reflected X-rays) among the X-rays emitted from the tip of the anode.

  One preferable aspect of the present invention is that the inspection set is mounted on a transfer robot whose transfer operation is controlled by a control computer.

  In a preferred aspect of the present invention, the angle of the outer peripheral slope of the anode tip portion with respect to the X-ray irradiation direction line is an angle at which the bundle diameter of the X-ray bundle generated from the target is smaller than the beam diameter of the electron beam from the annular electron emitter. It has been adjusted to.

  A preferred aspect of the present invention is that the imaging camera set is mounted on the transport robot, and both the imaging camera set and the inspection set are cooperatively controlled for inspection of the inspection object in accordance with a remote operation command from the control computer.

  The “conical shape” includes a conical shape and a pyramid shape. In this case, the entire circumference is not limited to the conical shape, and may be partially conical. The profile of the conical slope is not limited to a linear shape with a constant reduction ratio toward the tip, but has a shape (parabolic shape, etc.) in which the reduction ratio changes continuously or stepwise toward the tip. Alternatively, even a needle shape with a reduced diameter toward the tip can be included in the cone shape.

  The “annular” is not limited to a completely closed annular shape, and includes a partial annular shape.

  The “conical top” is not limited to a sharp top, and may include some roundness or the like.

  In a preferred aspect of the present invention, it is preferable that the anode tip has a heat conducting material having a larger heat capacity than the anode tip and capable of conducting heat generated at the anode tip to cool the anode tip.

  One preferable aspect of the present invention is a configuration in which the slope angle of the anode tip end portion is made smaller in a continuous exponential function or stepwise as the tip end of the anode tip end. In this aspect, by shifting the opposing position of the annular electron emitter and the target inclined surface in the axial direction, the bundle diameter of the X-ray bundle can be focused smaller, or conversely, the bundle diameter can be increased.

  Electron acceleration means may be disposed between the anode tip and the annular electron emitter. The annular electron emitter may be solid or hollow.

  The anode tip may be solid or hollow.

  In the first aspect of the present invention, the material inspection can be carried out more efficiently on the inner wall surface of the reactor vessel, the outer wall surface of the reactor internal structure, the inner wall surface of the pipe, and the like.

  In the second aspect of the present invention, even when there is an inspection object inside the reactor vessel or inside the piping, it can be set inside the X-ray inspection of the internal defect or the weld backside with higher accuracy by inspecting the welded part, for example. It can be.

  Hereinafter, an inspection system according to an embodiment of the present invention will be described with reference to the accompanying drawings.

(Embodiment 1)
Referring to FIG. 1, in order to perform material inspection, this inspection system includes an inspection set 1, an imaging camera set 3, a transport robot 5 that transports these sets 1 and 3 to a site to be inspected, and a control computer. 7.

  In the embodiment, for convenience of explanation, an example in which auxiliary devices such as a power source, a hardness meter used for material inspection, various microscopes, a mechanical polishing device, and the like are not mounted on the transfer robot 5 is shown. Even if such devices are mounted or not mounted, they are included in the inspection system of the embodiment. Although it is not limited to the kind of inspection object in embodiment, it is a reactor inner wall surface, a reactor internal structure outer wall surface, a piping inner wall surface, etc., for example. These are designated as wall surface 9 by reference numerals.

  The transfer robot 5 includes an inspection set 1, an imaging camera set 3, an electromagnet attracting member 10, and the like. The transfer robot 5 is connected to an external control computer 7 by a communication / power cable 11 in the embodiment, and is transferred along the wall surface 9 in response to a remote control command from the control computer 7 and inspected at an inspection target position. When the set 1 is conveyed, the conveyance of the imaging camera set 3 and the inspection set 1 is finished. The communication / power cable 11 is subjected to radiation shielding / protective coating treatment such as gamma rays.

  In the above inspection system, the image of the wall surface 9 can be displayed by the imaging camera set 3 while the transport robot 5 is self-running on the wall surface 9 under the control of the control computer 7, and the remote operation visual inspection can be performed using this image. When a defect such as a crack is detected on the wall surface 9 by this remote visual inspection, the inspection set 1 is used for a detailed inspection of the inspection target 13 such as a crack for the cause investigation, countermeasure, recovery, etc. Is done. The control computer 7 controls the movement of the transfer robot 5, the operation of the inspection set 1, the imaging camera set 3, and the electromagnet attracting member 10.

  2 and 3, the examination set 1 includes a radiation source 15 that irradiates an examination object with an electron beam as radiation, and an X-ray that detects characteristic X-rays (fluorescence X-rays) emitted from the examination object 13. And a detector 17. The inspection set 1 includes a sealing device 21 that seals the radiation source 15 and the inspection target 13 in the same vacuum space 19, a vacuum exhaust device 23 that exhausts the inside of the sealing device 21, and a drain device 24. Prepare.

  The radiation source 15 is supplied with operating power from the operating power supply 25 via the communication / power cable 11 under the control of the control computer 7.

  The X-ray detector 17 receives the operation power supply 25 via the communication / power cable 11 under the control of the control computer 7 and outputs a detection output to the control computer 7.

  The sealing device 21 includes a drainage / preliminary exhaust chamber 21a, a main exhaust chamber 21b, and an open / close door 21c.

  The drainage device 24 receives the operation power supply 25 from the communication / power cable 11 and drains the drainage / preliminary exhaust chamber 21 a in the sealing device 21 under the control of the control computer 7 from the communication / power cable 11.

  The vacuum evacuation device 23 receives supply of the operating power supply 25 from the communication / power cable 11 and evacuates the sealing device 21 under the control of the control computer 7 from the communication / power cable 11. The vacuum exhaust device 23 is connected to the drain / preliminary exhaust chamber 21a and the main exhaust chamber 21b by electromagnetic valves 23a and 23b, the electromagnetic valves 23a and 23b are closed, and the drain / preliminary exhaust chamber 21a is drained by the drain device 24. The electromagnetic valve 23a is closed, the electromagnetic valve 23b is opened, the drainage / preliminary exhaust chamber 21a is evacuated, the electromagnetic valve 23a is opened, the electromagnetic valve 23b is closed, and the main exhaust chamber 21b is evacuated.

  A vacuum seal 27 is attached to the sealing device 21. The vacuum seal 27 can be provided with a rubber vacuum seal or a magnetic fluid vacuum seal.

  The electromagnet attracting member 10 is energized and controlled by the control computer 7 via the communication / power cable 11 and attracts the transport robot 5 to the wall surface 9 by energization. With this magnitude control of energization, the suction force of the transfer robot 5 on the wall surface 9 can be controlled. The attracting form on the wall surface 9 of the transfer robot 5 is not limited to the electromagnet attracting member 10 and includes other attracting forms. The electromagnet attracting member 10 is provided with an electromagnet inside a heat resistant, oil resistant, acid resistant, pressure resistant, and radiation resistant elastic member, and is capable of elastic compression and elastic recovery. The magnetic force is variable by a control signal from the control computer 7 for the electromagnet.

  The transport robot 5 has a mounting base 5a for mounting the inspection set 1, an imaging camera set (including an electron microscope and an optical microscope) 3 and the like, and the mounting base 5a is free to run on the wall surface 9. Are equipped with a plurality of front wheels 5b and a plurality of rear wheels 5c that are heat resistant, oil resistant, acid resistant, pressure resistant, and radiation resistant. These wheels 5b and 5c are landed on the wall surface 9 by an electromagnetic attracting member 10 and are rotationally driven and controlled by a remote command from the control computer 7 so that the transport robot 5 can be controlled to move forward and backward, and an electromagnetic attracting member. 10, the sealing device 21 (to be described later) of the inspection set 1 can be pressed against the wall surface 9 in the state shown in FIGS.

  In the state of FIG. 2, the sealing device 21 has a vacuum exhaust chamber 21a and a preliminary exhaust chamber 21b separated by an opening / closing door 21c. When the preliminary exhaust chamber 21a is pressed against the wall surface 9 by the transfer robot 5 in the state shown in FIG. 3, the drainage / preliminary exhaust chamber 21a is drained by the drainage device 24 and then preliminary exhausted by the vacuum exhaust device 23. Is completed, the evacuation chamber 21a is evacuated, and when both the preliminary evacuation chamber 21a and the evacuation chamber 21a are evacuated, the open / close door 21c between the two evacuation chambers 21a and 21b is opened. In this way, it is possible to obtain a state in which the vacuum exhaust chamber 21a and the preliminary exhaust chamber 21b communicate with each other and the inspection target 13 and the inspection set 1 are vacuum-sealed in the same vacuum space 19.

  Due to the operation of the sealing device 21, the sealing device 21 is configured in a cover shape along the wall surface 9, and when draining and evacuating, the sealing device 21 is pressed against the wall surface 9 as described above. The gap between the sealing device 21 and the wall surface 9 is sealed, and the drainage and evacuation are performed in this state, whereby the sealing device 21 is evacuated. Further, the sealing device 21 is not limited to the cover shape. In addition, when there is no drainage target inside the wall surface 9, the drainage operation is not performed. Of course, when there is no water or the like at the inspection target position, it is not always necessary to equip the drainage device 24.

  As shown in FIG. 4, the radiation source 15 includes a field emission type electron emitter 15A provided with a nano carbon film 15b that emits electrons by field emission on the surface of the cathode 15a. The radiation source 15 further includes an electron beam extraction / focusing electrode 15d, an electron beam focusing electrode 15e, and an electron beam acceleration electrode 15f in the same case 15c. The application of voltage to the electron emitter 15A and the electrodes 15d-15f as the electron beam accelerating concentrator is controlled by the power source 5 under the control of the control computer 7.

  The nanocarbon film 15b has fine projections in the order of nm, such as carbon nanotubes, carbon nanowalls, carbon nanofibers, diamond-like carbon, amorphous diamond, crystalline diamond, graphite, fullerene, and acicular carbon films. In the radiation source 15, a negative DC voltage is applied from the power source 25 to the cathode 15a with the electron beam acceleration electrode 15f at the ground potential, and the electron beam 15d is acceleratedly irradiated from the electron emitter 15A to the inspection object 13 by each electrode 15d-15f. It is configured as follows.

  When the inspection target 13 such as a crack in the wall surface 9 is irradiated with an electron beam, characteristic X-rays are generated. Characteristic X-rays are X-rays generated by the transition of inner-shell electrons surrounding an element nucleus, and appear as several wavelengths (energy) inherent to the element. X-ray analysis is performed by spectrum measurement including the wavelength and intensity of this characteristic X-ray. There are various types of measurement, one of which is an energy dispersive type (EDS). The X-ray detector 17 includes a semiconductor detector such as a Si (Li) detector or a silicon drift detector. Since the X-rays incident on the X-ray detector 17 make a number of electron-hole pairs proportional to the energy, the energy of the incident X-rays can be known by taking out and measuring the number of electron-hole pairs. The control computer 7 performs material inspection from the X-ray detection signal transmitted from the X-ray detector 17. This material inspection is well known and will not be described in detail.

  The operation of the inspection system having the above configuration will be described. An operator operates the control computer 7 to move the transfer robot 5 along the wall surface 9 and activate the imaging camera set 3 to image the wall surface 9. Then, the imaging screen is displayed on the display screen of the control computer 7. Then, when it is determined that there is a suspicion that a crack or the like exists in the inspection target 13 by visual inspection, the inspection set 1 is operated, and the inspection target 13 is irradiated with an electron beam from the radiation source 15 of the inspection set 1. Characteristic X-rays are generated from the inspection object 13, the characteristic X-rays are detected by the X-ray detector 17, and the detection output is sent to the control computer 7. The control computer 7 displays an X-ray analysis image inside the inspection object 13 from the detection output. The worker performs material inspection of the inspection object 13 from the X-ray analysis image.

(Embodiment 2)
5 to 9 show an inspection system according to Embodiment 2 of the present invention. In these figures, parts corresponding to or similar to those in FIGS. 1 to 4 are denoted by the same reference numerals. 5 is a diagram showing the configuration of the inspection system according to the second embodiment corresponding to FIG. 2, FIG. 6 is a cross-sectional view of the X-ray tube, and FIG. 7 is an enlarged view of the appearance of the main part of the X-ray tube. . FIG. 8 is a diagram for explaining the operation of the X-ray tube, and FIG. 9 is a diagram showing a configuration in which the diameter of the X-ray irradiated from the X-ray tube is variable. In the second embodiment, the radiation source is configured by an X-ray tube that emits X-rays for X-ray inspection.

  As shown in FIG. 5, the inspection system of the second embodiment includes an inspection set 1, an imaging camera set 3, a transfer robot 5, an electromagnet attracting member 10, a control computer 7, a sealing device 21, and drainage. The apparatus 24 and the atmospheric | air pressure control apparatus 26 are provided.

  And this test | inspection set 1 is comprised by X-ray tube 15B. At the time of operation of the inspection system, the drainage / preliminary pressure control chamber 21a is drained by the drainage device 24 and controlled by the pressure control device 26, and then the main pressure control chamber 21b is controlled by the atmospheric pressure. When the atmospheric pressure control chamber 21b is controlled to the same atmospheric pressure, the open / close door 21c between the chambers 21a and 21b is opened. Thus, the atmospheric pressure in the space inside the sealing device 21 is controlled to, for example, atmospheric pressure. The sealing device 21 is preferably used for maintaining the inspection set 1 at a pressure such as atmospheric pressure when the pressure (water pressure or the like) at the inspection position of the inspection object 13 is high. If the atmospheric pressure is, for example, atmospheric pressure, it is not always necessary. In addition, the sealing device 21 can be used for waterproofing when water or the like is present at the inspection position of the inspection object 13, but is necessarily required if the inspection set 1 or the like has a waterproof structure. Not what you want.

  6 to 8, the X-ray tube 15B is configured as a vacuum tube 33. The X-ray tube 15B is a cylindrical straight tube that is long in the direction of the X-ray irradiation direction line L1, and the inside is evacuated. An anode 28, an annular electron emitter 29, and an electron shielding member 31 are provided. An X-ray derivation window 33a made of a thin film capable of transmitting X-rays is provided on the tube wall surface of the vacuum tube 33 on the X-ray irradiation direction side.

  The axial anode 28 is arranged so as to extend linearly in the X-ray irradiation direction line L1. An X-ray derivation window 33a is positioned in front of the X-ray irradiation direction line L1 of the anode tip 28a, which is the tip of the axial anode 28.

  The tip of the axial anode 28 has a conical slope 28a2 shape, and becomes an anode tip 28a where X-rays are generated by electron beam collision. The target material is not particularly limited. The rear side of the anode tip portion 28a of the shaft-like anode 28 has a large heat capacity and becomes a heat conducting portion 28b that conducts heat generated at the tip portion 28a, and a communication / power cable 11 (not shown) is connected to the rear side of the heat conducting portion 28b. Thus, a high voltage can be applied.

  The anode tip portion 28a has a conical shape in which the top portion 28a1 is located on the X-ray irradiation direction line L1 and the cone center line coincides with the X-ray irradiation direction line L1, and the conical slope 28a2 is in the X-ray irradiation direction line L1. On the other hand, the slope has a predetermined angle.

  The annular electron emitter 29 is configured by surrounding the X-ray irradiation direction line of the anode tip portion 28a annularly and providing a nanocarbon film 29b on the outer peripheral surface of the annular cathode 29a.

  The nanocarbon film 29b has fine nanometer-order protrusions such as carbon nanotubes, carbon nanowalls, carbon nanofibers, diamond-like carbon, amorphous diamond, crystalline diamond, graphite, fullerene, and acicular carbon film.

  The annular electron emitter 29 emits electrons toward the anode tip portion 28a radially inward by emitting an electric field by applying an electric field to the anode tip portion 28a. The electric field is applied by applying a high potential from the power source 25 to the anode tip 28a, for example. There are various potential application modes, and this embodiment mode is not particularly limited.

  For example, the power source may be a pulse power source controlled by the control computer 7, and an extremely short pulse may be applied from the pulse power source to the anode tip 28 a under the control of the control computer 7. For example, a pulse is generated by applying a positive pulse voltage + V to the target and a negative pulse voltage −V having the same absolute value as the positive pulse voltage + V in synchronization with the positive pulse voltage + V to the annular electron emitter 29. The magnitude of the power supply voltage may be controlled in half. The waveform of the pulse voltage may be a rectangular wave, a sawtooth wave, or other waveform shapes.

  The electron shielding member 31 is an electron shielding member that is arranged on both sides of the annular electron emitter 29 in the X-ray irradiation direction and shields electrons emitted from the annular electron emitter 29 in both axial directions. A pair of annular plate portions 31a and 31b on both sides and a cylindrical portion 31c connecting the both annular plate portions 31a and 31b are provided. The inner diameters of the annular plate portions 31 a and 31 b are smaller than the inner diameter of the annular electron emitter 29. The electron shielding member 31 is applied with the same or substantially the same potential as the annular electron emitter 29.

  When a high pulse voltage is applied to the anode tip portion 28 a, a high electric field is applied between the anode tip portion 28 a and the annular electron emitter 29. As a result, electrons are emitted from the annular electron emitter 29 toward the anode tip portion 28a by field emission, and the emitted electrons collide with the conical slope 28a2 of the anode tip portion 28a.

  When electrons collide with the conical slope 28a2, X-rays are generated from the conical slope 28a. This X-ray goes straight in the X-ray irradiation direction line L1, and irradiates the inspection target 13 such as a welded portion outside the window in a spot shape from the X-ray derivation window 33a.

  In this case, the electrons emitted from the annular electron emitter 29 are shielded by the electron shielding member 31 to cause the electrons to collide with the anode tip portion 28a. At this time, by adjusting the facing distance and the inner diameter of the annular plate portions 31a and 31b. The electrons in the trajectory indicated by the broken line are shielded, and only the electrons in the trajectory indicated by the solid line collide with the anode tip portion 28a as a narrow electron beam. Therefore, by making the inner diameters of the annular plate portions 31a and 31b of the electron shielding member 31 smaller than the inner diameter of the annular electron emitter 29, the electrons emitted from the annular electron emitter 29 are converted into electron beams having a narrower spread as the anode tip portion 28a. Can collide with.

  As a result, the bundle diameter of the X-ray bundle generated from the conical slope 28a2 of the anode tip 28a can be narrowed down, and X-rays can be irradiated to the inspection object 13 in the form of an X-ray irradiation spot.

  Further, by adjusting the angle of the conical slope 28a2 of the anode tip portion 28a, even if the beam diameter of the electron beam colliding with the conical slope 28a2 of the anode tip portion 28a is the same, X generated from the conical slope 28a2 of the anode tip portion 28a. The bundle diameter of the wire bundle can be narrowed down.

  Referring to FIG. 9, the bundle diameter of the X-ray bundle is set to the first bundle diameter D1 by setting the annular electron emitter 29 and the electron shielding member 31 at the position d11 in FIG. 9A, and FIG. The bundle diameter of the X-ray bundle is set to the second bundle diameter D2 (<D1) by setting at the position d12, and the bundle diameter of the X-ray bundle is set to the third bundle diameter by setting at the position d13 in FIG. 9C. Each can be set to D3 (<D2). Thereby, the X-ray irradiation spot 49 with respect to the test object 13 can be adjusted to an arbitrary spot diameter.

  The operation of the inspection system of the second embodiment having the above configuration will be described. An operator operates the control computer 7 to move the transfer robot 5 on the wall surface 9 and operates the imaging camera set 3 to move the wall surface. The inside is imaged, and the imaging screen is displayed on the display screen of the control computer 7. Then, when it is found by visual inspection that there is a suspicious portion of the weld back of the welded portion or a defect in the inspection target 13, the inspection set 1 is activated, and an electron beam is passed from the electron emitter 29 of the inspection set 1 to the anode tip 28a. And the inspection object 13 is irradiated with X-rays generated from the anode tip portion 28a. The X-rays pass through the inspection object 13 and are irradiated to the X-ray film 26 behind it. An operator carries out an X-ray inspection of the inspection object 13 using an X-ray film irradiated with transmitted X-rays, and clarifies the defect.

  FIG. 10 further describes Embodiment 3 of the present invention. In Embodiment 3, X-rays from the anode tip portion 28a are reflected rather than transmitted through the inspection object. This reflected X-ray is detected by an X-ray CCD camera 32 or the like. In such a case, when the wall thickness of the wall surface 9 is thick, the X-ray is not transmitted but reflected so that the inspection target 13 can be inspected more easily.

  The present invention is not limited to the above-described embodiment, and includes various changes or modifications within the scope described in the claims.

FIG. 1 is a diagram showing a schematic configuration of an inspection system according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view showing an inspection set mounted on the transfer robot in the above inspection system, in particular, a state where the sealing device is not pressed against the inner wall of the pipe. FIG. 3 corresponds to FIG. 2 and is a sectional view showing a state in which the sealing device is pressed against the inner wall of the pipe. FIG. 4 is a diagram showing a schematic configuration of a radiation source arranged in the sealing device. FIG. 5 is a diagram showing a schematic configuration of the inspection system according to the second embodiment. FIG. 6 is a diagram showing a schematic configuration of a radiation source used in the second embodiment. FIG. 7 is a perspective view showing a part of the radiation source of FIG. FIG. 8 is a diagram for explaining the operation of the radiation source of FIG. FIG. 9 is a diagram showing a configuration for arbitrarily narrowing the bundle diameter of the X-ray bundle. FIG. 10 is a diagram showing a schematic configuration of an inspection system used in the third embodiment. FIG. 11 is a diagram partially showing the reactor vessel, the reactor internal structure, and the piping.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inspection set 3 Imaging camera set 5 Transfer robot 5a Mount stand 5b Front wheel 5c Rear wheel 7 Control computer 9 Wall surface 10 Electromagnetic adsorption member 11 Communication / power cable 13 Inspection object 15 Radiation source 17 X-ray detector 19 Vacuum space 21 Sealing device 23 Vacuum exhaust device 24 Drainage device 25 Power supply 27 Vacuum seal 28 Axial anode 29 Annular electron emitter 31 Electron shielding member

Claims (10)

An inspection set mounted on the transfer robot and capable of movement control, and a control computer for controlling the operation of the inspection set from a remote location;
The inspection set includes an anode tip extending in a conical shape on the X-ray irradiation direction line, a field emission-type annular electron emitter surrounding the anode tip in a ring shape, and at least the annular electron emitter with respect to the annular electron emitter. An inspection system comprising: an electron shielding member disposed on both sides in the X-ray irradiation direction ; and an X-ray extraction window made of a thin film capable of transmitting X-rays on the tube wall of the vacuum tube in front of the anode tip portion . The inspection system according to claim 1 , wherein the annular electron emitter is provided with a nanocarbon film that emits an electron beam as radiation by electric field radiation on the annular cathode surface. Inspection system according to claim 1, characterized with a heat-conducting element to the rear the anode tip end part, that. The electron shield member, the inspection system according to any one of claims 1 to 3 around the X-ray irradiation direction are arranged annularly, it is characterized. The inspection system according to claim 4 , wherein the electron shielding member has an annular plate structure having an inner diameter smaller than an inner diameter of the annular electron emitter. The electron shielding member includes a pair of annular plate portions that are arranged annularly around the X-ray irradiation direction on both sides of the annular electron emitter in the X-ray irradiation direction and have an inner diameter smaller than the inner diameter of the annular electron emitter. The inspection system according to any one of claims 1 to 3 . The inspection system according to any one of claims 1 to 6 , wherein the annular electron emitter and the electron shielding member are integrally movable back and forth in the X-ray irradiation direction with respect to the anode tip. . The inspection system according to any one of claims 1 to 7 , wherein the inspection set is covered with a sealing device in the same space together with an inspection target, and the pressure inside the sealing device internal space can be controlled. Inspection system according to any one of claims 1 to 8 X-rays emitted from the anode tip, detects the transmitted X-rays with which transmits the test object (transmission X-rays), characterized in that. Inspection system according to any one of claims 1 to 8 to detect the reflected X-rays with reflecting X-rays radiated from the anode tip in the test object (reflection X-ray), characterized in that.

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