JP6223914B2 - Canister inspection method and inspection apparatus - Google Patents

Description

  The present invention relates to an inspection method and an inspection apparatus for a metal sealed container (referred to as a canister) for storing spent nuclear fuel.

  A system in which spent nuclear fuel is sealed in a cylindrical metal sealed container (canister) and then stored in a concrete container to store spent nuclear fuel safely is called a concrete cask.

  Although the concrete container has multiple ventilation holes for heat removal, it has the function of natural cooling without having an external power supply, but sea salt particles contained in the outside air may adhere to the canister surface. . For this reason, when long-term storage is continued for several decades, there is a concern that pitting corrosion on the canister surface and stress corrosion cracking associated therewith may occur. Stress corrosion cracking causes cracks to grow from the surface of the canister. If a crack penetrates the canister, helium gas or radioactive gas filled in the canister leaks. In order to eliminate this possibility as much as possible, it is important to periodically check the health of the canister.

  As a conventional method for inspecting a canister, for example, a fiberscope or the like is inserted into a concrete container to inspect the appearance (Patent Document 1), and a temperature sensor or the like is inserted into the concrete container to detect an abnormality in the canister. (Patent Document 2), a method of inspecting the appearance by inserting a robot equipped with a camera or the like in a concrete container (Patent Document 3), and inserting a gas sampling capillary into the concrete container There are a method for detecting leakage (Patent Document 4) and a method for detecting the presence or absence of salt by laser irradiation or the like by inserting a duct into a concrete container (Patent Document 5).

JP 2004-0661206 A JP-A-2005-308419 JP 2003-194729 A JP 2009-115691 A JP 2007-271634 A

  However, all of the methods of Patent Documents 1 to 5 are provided in a concrete container because various devices are inserted into the concrete container in which the canister is stored (that is, the canister storage space). It is not easy to bring the equipment close to the entire peripheral surface of the canister due to a heat shield or the like. Therefore, it takes a lot of labor and time to inspect the entire peripheral surface of the canister. There is a problem that some parts of the canister side peripheral surface cannot be inspected depending on the structure in the concrete container. For this reason, it is difficult to say that the canister inspection method is perfect, and as a result, the reliability of the inspection result of the canister cannot be said to be high.

  In the methods of Patent Documents 1 to 5, since the insertion port for inserting the device into the concrete container is narrow and bent, it takes a lot of labor and time to insert the device. There is a problem that the inspection time is assumed to be prolonged, and in addition, in order to perform various inspections, the equipment is replaced for each inspection (that is, the equipment inserted in the concrete container is taken out and another equipment is inserted) Work) is required, and the inspection time is further prolonged. And the problem that an exposure amount of an operator increases by prolonging inspection time is caused.

  Therefore, the present invention is capable of reliably performing at least the inspection of the entire canister side peripheral surface and reducing the labor and time required for the inspection of the entire canister side peripheral surface. An object of the present invention is to provide an inspection method and an inspection apparatus for a nuclear fuel storage canister.

  In order to achieve such an object, the canister inspection method of the present invention includes a peripheral wall provided with at least one of an apparatus door, an observation window, and a door with a window, and a ceiling portion that closes one end of the peripheral wall. A main body in which the canister is accommodated in the internal space, an opening / closing mechanism for closing and opening the opening at the other end of the peripheral wall of the main body, and a canister stored in a storage container for storing the canister A canister inspection device having a transfer mechanism for transferring into the internal space of the main body and a rotation mechanism for rotating the canister in the internal space of the main body with respect to the main body in contact with the storage container. Open the opening at the other end of the peripheral wall, transfer the canister stored in the storage container into the internal space of the main body by the transfer mechanism, and open the opening at the other end of the peripheral wall of the main body by the opening / closing mechanism The canister is inspected using at least one of the device door, the observation window, and the door with the window provided on the main body while the canister is axially rotated with respect to the main body by the rotation mechanism after being closed. I have to.

  The canister inspection apparatus of the present invention has a peripheral wall provided with at least one of an apparatus door, an observation window, and a door with a window, and a ceiling portion that closes one end of the peripheral wall in an internal space. A main body in which the canister is accommodated, an opening / closing mechanism for closing and opening an opening at the other end of the peripheral wall of the main body, and a canister stored in a storage container for storing the canister are disposed in the internal space of the main body. And a rotation mechanism for rotating the canister in the internal space of the main body with respect to the main body.

  Therefore, according to these canister inspection methods and inspection apparatuses, the canister is pivoted with respect to the main body, so that the device door and the observation window provided on the peripheral wall of the main body are only in one place each. Even if there is, or even if there is only one door with a window, the inspection and visual confirmation of the entire surface of the side peripheral surface of the canister can be performed.

  According to these canister inspection methods and inspection apparatuses, the canister is rotated with respect to the main body, so that the inspection relating to the soundness of the canister is continuously performed over the entire peripheral surface of the canister. Done.

  According to these canister inspection methods and inspection apparatuses, since the canister inspection apparatus and the container for storing the canister are connected to each other through the internal spaces, radiation generated from the canister surface can be obtained. Inspection work is performed while shielding radiant heat.

  Also, the canister inspection method of the present invention is provided on the canister while maintaining a constant distance between the canister and the holding portion, which is provided on the canister side of the holding portion and holding the probe. The object side moving mechanism capable of moving the part and the holding part against the structure on the opposite side of the canister while being urged in the direction of pressing the holding part against the canister side, provided on the side opposite to the canister of the holding part A device having an urging-side moving mechanism capable of moving the canister may be inserted between the inner peripheral surface of the peripheral wall of the main body and the side peripheral surface of the canister, and the canister may be inspected. The canister inspection apparatus is provided on the canister side of the holding unit that holds the probe and moves the holding unit relative to the canister while maintaining a constant distance between the canister and the holding unit. The object-side moving mechanism that can be moved and the holding part that is provided on the opposite side of the canister, the holding part is moved relative to the structure on the opposite side of the canister while urging the holding part in a direction to press it against the canister. A device having an urging-side moving mechanism to be obtained may be inserted between the inner peripheral surface of the peripheral wall of the main body and the side peripheral surface of the canister. In these cases, the urging-side moving mechanism comes into contact with the structure on the side opposite to the canister, and the urging force of the urging-side moving mechanism acts on the object-side moving mechanism via the holding unit, and as a result The object side moving mechanism is pressed against the surface of the canister.

  According to the canister inspection method and inspection apparatus of the present invention, even if there is only one device door or observation window provided on the peripheral wall of the main body or only one door with a window, the canister side Since the entire surface of the peripheral surface can be inspected and visually confirmed, it is possible to ensure that at least the entire surface of the peripheral surface of the canister is inspected to ensure a perfect inspection method for the canister. As a result, the canister It is possible to improve the reliability of the inspection results. Furthermore, it is possible to reduce labor and time required for the inspection of the entire peripheral surface of the canister.

  According to the canister inspection method and inspection apparatus of the present invention, the inspection related to the canister soundness can be continuously performed at least over the entire peripheral surface of the canister. It is possible to rationalize time reduction.

  According to the canister inspection method and inspection apparatus of the present invention, since the inspection work can be performed while shielding the radiation and radiant heat generated from the canister surface, the safety of the worker can be ensured.

  Furthermore, the canister inspection method and inspection apparatus according to the present invention includes an object side moving mechanism that maintains a constant distance between the canister and the holding portion, and an urging side moving mechanism that urges the holding portion toward the direction of pressing the canister. In this case, since the object-side moving mechanism is pressed against the surface of the canister, the distance between the structure on the opposite side of the canister and the canister changes. The distance between the canister and the holding part is kept constant. Therefore, the distance and relative distance between the probe and the canister fixed to the holding part can be kept constant, and the inspection conditions are kept constant. The inspection accuracy can be improved, and the probe can be prevented from being damaged by being strongly pressed against the canister more than necessary.

It is a perspective view for overlooking the whole structure of the inspection apparatus of the canister of an embodiment, a canister, and a concrete container. It is an elevation view which shows the canister and concrete container in embodiment, and is a figure showing the concrete container as a longitudinal section. It is a perspective view which shows an example of how to provide the apparatus door and observation window in the main body of the inspection apparatus of a canister. It is an elevation view which shows the state when a canister is lifted when moving a canister from the concrete container of an embodiment to the inspection apparatus of a canister, and is a figure showing the inspection apparatus of a concrete container and a canister as a longitudinal section. It is an elevational view showing a state where the canister is housed in the canister inspection apparatus of the embodiment, and is a view showing the canister inspection apparatus as a longitudinal section. It is a top view which shows the connection part of the inspection apparatus of the canister of embodiment. (A) is a figure of the state by which the opening was closed. (B) is a figure of the state by which the opening was open | released. It is a side view which shows the gap | interval approach apparatus of embodiment (The surrounding wall of a canister and the surrounding wall of the main body of the inspection apparatus of a canister are represented as a longitudinal cross-section.). It is a figure showing a gap approach device of an embodiment. (A) is a plan view (in other words, a surface of the canister on the inspection device side). (B) is a back view (in other words, a surface on the canister side). It is a figure which shows other embodiment of the inspection apparatus of a canister, Comprising: It is a side view of the inspection apparatus of a canister when accommodated in a concrete container in the attitude | position which made the axial direction the horizontal direction, a concrete container, It is the figure which represented the inspection apparatus of the canister as a longitudinal section. It is an elevational view showing still another embodiment of a canister inspection device, and is a view showing the canister inspection device as a longitudinal section.

  Hereinafter, the configuration of the present invention will be described in detail based on an example of an embodiment shown in the drawings.

  1 to 8 show an example of an embodiment of a canister inspection method and inspection apparatus according to the present invention.

  1 to 10 are merely schematic structural diagrams for explaining the configuration of the present invention. The structure of each part is simplified and does not strictly show the detailed structure, and the dimensions of each part are also shown. The relative relationship is also not strict. Specifically, for example, the detailed structure of the canister 10 and the detailed structure such as a vent hole for heat removal provided in the concrete container 11 are omitted. Moreover, in FIG. 1, illustration of the opening / closing mechanism 4 provided in the connection part 3, the raising / lowering apparatus 6 attached to the rotating apparatus 5, and the wire rope 7 is abbreviate | omitted.

  In the present embodiment, a case where a canister 10 (FIG. 2), which is a cylindrical metal sealed container in which spent nuclear fuel is put and usually stored and stored in a concrete container 11, is inspected, is taken as an example. explain. The inspection object to which the present invention can be applied is not limited to a canister stored and stored in the concrete container 11, but may be a canister stored and stored in another storage container. Absent.

  The concrete container 11 includes a main body 11a having a cylindrical peripheral wall and a bottom portion that closes a lower end of the peripheral wall, and an upper lid 11b that is detachably attached to the upper end opening of the main body 11a.

  The canister inspection apparatus 1 according to this embodiment includes a peripheral wall 2a provided with at least one of an apparatus door, an observation window, and a door with a window, and a ceiling portion 2b that closes one end of the peripheral wall 2a. The main body 2 in which the canister 10 is accommodated in the internal space 2g, the opening / closing mechanism 4 for closing and opening the opening at the other end of the peripheral wall 2a of the main body 2, and a storage container for storing the canister ( In this embodiment, the lifting device 6 and the wire rope 7 as a transfer mechanism for transferring the canister 10 stored in the concrete container 11) into the internal space 2g of the main body 2, and the canister 10 in the internal space 2g of the main body 2 are used. A rotating device 5 as a rotating mechanism for rotating the shaft relative to the main body 2 and a wire rope 7.

  In the canister inspection method of the present embodiment, the opening at the other end of the peripheral wall 2a of the main body 2 is opened by the opening / closing mechanism 4 with the canister inspection device 1 in contact with the storage container (concrete container 11). The canister 10 stored in the storage container (concrete container 11) is transferred into the internal space 2g of the main body 2 by the transfer mechanism (elevating device 6 and wire rope 7), and the opening / closing mechanism 4 After closing the opening at the other end, the canister 10 is pivoted with respect to the main body 2 by the rotation mechanism (the rotating device 5 and the wire rope 7), and the device door, the observation window, and the window provided in the main body 2 are attached. The canister 10 is inspected using at least one of the doors. In the present embodiment, the wire rope 7 functions as a part of the transfer mechanism and also functions as a part of the rotation mechanism.

  The main body 2 is for accommodating the canister 10 to be inspected, and has a cylindrical peripheral wall 2a and a ceiling portion 2b that closes the upper end of the peripheral wall 2a. The form of the peripheral wall 2a is not limited to a cylindrical shape, and may be a rectangular tube shape.

  The main body 2 is formed of, for example, stainless steel, super stainless steel, or duplex stainless steel, similarly to the canister 10.

  A probe of an inspection apparatus that inspects the canister 10 is inserted into the main body 2 or connected to a probe that is inserted into the main body 2 and used for inspection into the peripheral wall 2a and the ceiling 2b of the main body 2. An openable / closable device door for allowing the signal cable to pass therethrough and an observation window for viewing the canister 10 are provided, and if necessary, the internal space 2g of the main body 2 (that is, the canister 10 is accommodated). And a small tube for performing gas sampling in communication with the space.

  Regarding the observation window, radiation is shielded by using a lead window, and radiation heat is shielded by attaching a heat shielding film to the window. As a result, the operator can perform the inspection safely.

  In addition, since the bent duct is attached to the apparatus door or the observation window, the shielding effect of radiation and radiant heat is increased.

  Note that the apparatus door and the observation window may be provided as an integrated unit that realizes both functions. That is, an openable / closable door (referred to as a door with a window) provided with a window portion for viewing the canister 10 may be provided.

  Further, the appearance inspection (in other words, visual inspection) of the canister 10 may be performed using a camera, and only the device door may be provided and the observation window may not be provided. Alternatively, when only the appearance inspection is performed by visually observing the canister 10, only the observation window may be provided and the apparatus door may not be provided.

  The number, position, and size of the device door, observation window, or door with window provided in the main body 2 are not limited to specific ones, and are appropriately selected based on the contents of the inspection of the canister 10. Can be set

  Specifically, for example, as shown in FIG. 3, it is conceivable that an apparatus door 2d is provided on the peripheral wall 2a of the main body 2, and an observation window 2f is provided on the ceiling portion 2b. In FIG. 3, reference numeral 2e denotes a passage communicating with the internal space 2g of the main body 2 that is opened or closed by the apparatus door 2d.

  In this case, the device door 2d is provided at a substantially central position in the vertical direction of the internal space 2g of the main body 2 as having a size required based on the size of the probe or signal cable used for inspection. It is preferred that

  In this case, the observation window 2f is dimensioned in the horizontal radial direction so that the center point of the upper surface of the canister 10 can be seen from the window at the approximate center position of the cross-sectional radius in the horizontal direction of the internal space 2g of the main body 2. It is preferable to provide as what has. Alternatively, the number of observation windows 2f and the sizes of the observation windows 2f may be adjusted so that the visual field from a plurality of windows is connected so that the center point of the upper surface of the canister 10 can be viewed from the periphery.

  In the case where an observation window or a door with a window is provided on the peripheral wall 2a of the main body 2, the window extends from the upper end to the lower end of the side peripheral surface of the canister 10 at a substantially central position in the vertical direction of the internal space 2g of the main body 2. It is preferable to be provided as having a dimension in the vertical direction that can be seen from the part. Alternatively, the number and size of observation windows or doors with windows may be adjusted so that the top and bottom ends of the side peripheral surface of the canister 10 can be viewed by connecting the fields of view from a plurality of windows. good.

  The connecting portion 3 is attached to the lower end of the peripheral wall 2a of the main body 2 so that the main body 2 and the concrete container 11 are connected when the internal space 2g of the main body 2 communicates with the internal space of the main body 11a of the concrete container 11. It is interposed between the two and controls closing and opening of the internal space 2g of the main body 2.

  The connection part 3 has an opening 3a that faces the opening of the peripheral wall 2a of the main body 2 and becomes the boundary with the outside (the aspect for the connection part 3 is a through hole), and closes or opens the opening 3a. An opening / closing mechanism 4 is provided.

  The opening 3 a of the connecting portion 3 is provided at an inner position (in other words, an inner range) of the peripheral wall 2 a of the main body 2.

  The lower surface of the portion surrounding the opening 3a in the connecting portion 3 (that is, the portion corresponding to the frame of the opening 3a) is spaced from the upper end surface of the main body 11a when installed on the upper end of the main body 11a of the concrete container 11. Abut without contact.

  The opening / closing mechanism 4 closes or opens the internal space 2g of the main body 2 by closing or opening the opening 3a of the connecting portion 3 facing the opening of the peripheral wall 2a of the main body 2. It has two doors 4A and 4B accommodated in the connection part 3, and a horizontal drive device (illustration omitted).

  The two doors 4A and 4B are disposed in a door accommodating space 3b formed as an intermediate layer of the connecting portion 3 so that opposite sides abut each other, and an upper surface and a lower surface are slid with an inner surface of the door accommodating space 3b. Contained to be movable.

  Then, the two doors 4A and 4B are horizontally moved by the horizontal driving device so as to close and open the opening 3a of the connecting portion 3.

  An observation window may be provided on at least one of the two doors 4A and 4B. As a result, the bottom surface of the canister 10 can be visually checked, and the entire surface of the canister (that is, the top surface, the side peripheral surface, and the bottom surface) can be surely inspected to further ensure the canister inspection method. As a result, it becomes possible to further improve the reliability of the inspection result of the canister.

  Note that the observation windows provided on the doors 4A and 4B can be seen from the center point of the bottom surface of the canister 10 to the peripheral edge at a substantially central position of the cross-sectional radius in the horizontal direction of the internal space 2g of the main body 2 of the canister inspection apparatus 1. It is preferable to be provided as having a dimension in the horizontal radial direction. Alternatively, the number of observation windows and the size of each observation window may be adjusted so that the visual field from a plurality of windows is connected so that the center point to the periphery of the bottom surface of the canister 10 can be viewed.

  The opening / closing mechanism 4 is not limited to the configuration having the two doors 4A and 4B as described above as long as the opening of the peripheral wall 2a of the main body 2 is closed or opened. Specifically, for example, it may be an armor door (in other words, a shutter) that is rolled up in a bowl shape or unrolled and unfolded in a flat shape, or it may be folded into a bellows shape or folded. It is also possible to have a mode in which the surface is expanded and expanded in a planar shape.

  And when the connection part 3 is also installed in the upper end of the main body 11a of the concrete container 11 interposed between the main body 2 and the concrete container 11, including adapting to the mode of the opening / closing mechanism 4, the main body 11a The structure shown in FIG. 6 or the like is not limited as long as it is in contact with the upper end surface without a gap.

  On the upper surface of the ceiling 2b of the main body 2, a rotating device 5 and a pair of lifting devices 6 and 6 (in other words, a hoisting device) attached to the rotating device 5 are provided.

  The rotating device 5 is for rotating the canister 10 with respect to the main body 2. The base 5 a is fixedly attached to the upper surface of the ceiling portion 2 b of the main body 2, and is horizontally rotatable on the base 5 a. And a pedestal 5b to be supported.

  The pedestal 5b of the rotating device 5 rotates horizontally with respect to the base 5a by a rotation driving device (not shown).

  Each lifting / lowering device 6 is for winding and sending out the wire rope 7.

  The lower end of each wire rope 7 is detachably connected to the canister 10 via a rope connecting portion 10a. That is, two wire ropes 7, 7 arranged in parallel are connected to the canister 10.

  The rope connecting portion 10a is not limited to a specific mechanism, and any mechanism may be used as long as the tip of the wire rope 7 can be detachably connected. Moreover, the mechanism for connecting with the rope connection part 10a is provided also in the front end side of the wire rope 7 as needed. Specifically, for example, the rope connecting portion 10a is configured as a pair of trunnion pins protruding in opposite directions in the radial direction of the canister 10 and is provided on the upper surface of the canister 10, and each of the trunnion pins It is conceivable that a gripping tool 7 a having a pair of hooks to be locked is provided at the tip of the wire rope 7.

  The ceiling 2b of the main body 2 is provided with a through hole 2c that communicates with the internal space 2g, and the rotating device 5 is provided with a through hole 5c that communicates with the through hole 2c, and these through holes 2c and 5c are connected to the wire rope 7. Pass through.

  The pair of elevating devices 6 and 6 are fixedly attached to the upper surface of the rotating device 5 (that is, the upper surface of the pedestal 5b) at positions facing each other with the through hole 5c interposed therebetween.

  And the canister 10 connected with the lower end of the wire rope 7 raises / lowers when the wire rope 7 is wound up or sent out by the raising / lowering device 6.

  Further, when the pedestal 5b of the rotating device 5 rotates horizontally, the pair of lifting devices 6 and 6 fixedly attached to the upper surface of the pedestal 5b are horizontally turned.

  Then, the movement of the pair of lifting devices 6, 6 rotating horizontally is transmitted by the two wire ropes 7, 7, and the canister 10 rotates with respect to the main body 2.

  In this way, the canister 10 pivots with respect to the main body 2, so that a plurality of inspection probes are not inserted into the main body 2 or moved on the surface of the canister 10 in the circumferential direction. It is possible to inspect and visually confirm the entire side peripheral surface of the canister 10 without providing a plurality of the peripheral walls 2a of the main body 2. Then, by reducing the number of observation windows as much as possible, it is possible to reduce radiation and radiant heat emitted to the outside.

  Here, when non-contact type inspection is performed using a probe, the surface of the canister 10 is contacted with the non-contact type probe in order to make the inspection conditions constant at the beginning and end of the inspection performed by the non-contact type probe. In some cases, it is required to keep the separation distance from the touch element constant. Further, when a contact type inspection is performed using a probe, the strength of the contact type probe coming into contact with the surface of the canister 10 is kept constant so that the contact type probe is not damaged. It may be required to keep the relative distance of the contact probe relative to the 10 surfaces constant.

  Therefore, when the canister 10 is inspected, if necessary, between the inner peripheral surface of the peripheral wall 2a of the main body 2 of the canister inspection apparatus 1 and the side peripheral surface 10b of the canister 10 (in other words, the outer peripheral surface). The inserted gap entry device 8 may be used.

  As shown in FIGS. 7 and 8, the gap approach device 8 of the present embodiment includes a holding portion 8a that holds the probe 9, and a canister 10 and a holding portion 8a that are provided on the canister 10 side of the holding portion 8a. A fixed long axis 8b and an object side wheel 8c supported by the fixed long axis 8b as an object side moving mechanism capable of moving the holding portion 8a with respect to the canister 10 while keeping the distance between the fixed long axis 8b and The holding portion 8a is biased in the direction of pressing the holding portion 8a against the canister 10 side, which is provided on the opposite side of the holding portion 8a to the canister 10 (in this embodiment, on the peripheral wall 2a side of the main body 2 of the canister inspection device 1). However, the structure is on the opposite side of the canister 10 (in this embodiment, the peripheral side wall 2a of the main body 2 of the canister inspection device 1), and is urged and extended as an urging side moving mechanism that can move the holding portion 8a. Bullet And a biasing side wheel 8e supported by the telescopic shaft 8d and the telescopic shaft 8d to stretch.

  The holding portion 8a is for holding the probe 9 used for the inspection of the canister 10, and has a structure / mechanism 8f for fixing the probe 9 of the inspection apparatus selected according to the content of the inspection. And a structure / mechanism 8g for fixing a part of the signal cable 9a connected to the probe 9 near the probe 9 as necessary. The structures / mechanisms 8f and 8g for fixing the probe 9 and the signal cable 9a are formed to match the shape of the probe 9 and the like.

  The signal cable 9a passes through a device door 2d provided on the peripheral wall 2a of the main body 2 (in FIG. 7, a passage 2e opened or closed by the device door provided on the outer peripheral surface side of the peripheral wall 2a). And is connected to an inspection device (not shown) disposed outside the inspection device 1 of the canister.

  Four fixed long shafts 8b are attached to the holding unit 8a on the side of the canister 10 to be inspected. These fixed long axes 8b have a constant length and do not expand and contract. Note that the number of the fixed long shafts 8b is not limited to four as long as the posture of the holding portion 8a can be stabilized.

  An object-side wheel 8c is attached to the tip of each fixed long shaft 8b so as to be rotatable in all directions. Note that a plurality of object-side wheels 8c may be attached to one fixed long axis by using, for example, a plurality of branch legs extending radially in the axial direction.

  The object-side moving mechanism can be a fixed long shaft 8b and wheels 8c as long as the holding unit 8a can be moved relative to the canister 10 while keeping the distance between the canister 10 and the holding unit 8a constant. It is not limited to the structure which consists of. Specifically, for example, a configuration in which the holding portion 8a directly supports the wheel axle may not have the fixed long shaft 8b, or a hemisphere formed of a slidable and non-deformable material is formed in the holding portion 8a. The structure which can be attached may be sufficient.

  Four telescopic shafts 8d are attached to the holding portion 8a on the side opposite to the canister 10, that is, on the side of the peripheral wall 2a of the main body 2 of the canister inspection device 1. The number of the telescopic shafts 8d is not limited to four as long as the posture of the holding portion 8a can be stabilized.

  These telescopic shafts 8d are capable of expanding and contracting in the axial direction, and always try to extend as the entire length of the shaft in a state where the gap approach device 8 is installed between the canister 10 and the peripheral wall 2a (in other words, Configured to be stretched). In other words, the telescopic shaft 8d is configured to be elastically expanded by being extended and biased, whereby the holding portion 8a is urged in a direction to be pressed against the canister 10.

  The mechanism for allowing the elastic shaft 8d to elastically expand and contract is not limited to a specific one. Specifically, for example, it is constituted by an outer rod, an inner rod inserted into the outer rod, and a compression coil spring disposed inside the outer rod so as to be interposed between the outer rod and the inner rod. A mechanism is considered. Alternatively, a gas spring may be used as the telescopic shaft 8d.

  An urging wheel 8e is attached to the tip of each of the telescopic shafts 8d so as to be rotatable in all directions. A plurality of biasing wheels 8e may be attached to one telescopic shaft by using, for example, a plurality of branch legs extending radially at right angles in the axial direction.

  The urging side moving mechanism urges the holding portion 8a toward the canister 10 while urging it in the direction opposite to the canister 10 (in this embodiment, the peripheral wall 2a of the main body 2 of the canister inspection device 1). As long as the holding part 8a can be moved with respect to), the structure is not limited to the structure including the telescopic shaft 8d and the wheel 8e. Specifically, for example, a hemisphere formed of a slidable and elastically deformable material may be attached to the holding portion 8a.

  With the above-described configuration of the gap entry device 8, the urging side wheel 8e comes into contact with the inner peripheral surface of the peripheral wall 2a of the main body 2 of the canister inspection device 1, and the urging force by the telescopic shaft 8d is transmitted through the holding portion 8a. As a result, the object side wheel 8c is pressed against the side peripheral surface 10b of the canister 10.

  Thereby, even if the distance between the side peripheral surface 10b of the canister 10 and the inner peripheral surface of the peripheral wall 2a of the main body 2 of the canister inspection device 1 changes, the inner peripheral surface of the peripheral wall 2a of the main body 2 of the canister inspection device 1 The distance between the side peripheral surface 10b of the canister 10 and the holding portion 8a of the gap approach device 8 is kept constant by changing the distance between the holding portion 8a of the gap approach device 8 and the holding portion 8a. The distance and the relative distance between the probe fixed to 8a and the side peripheral surface 10b of the canister 10 are kept constant.

  Further, the gap approach device 8 is fixed in position so that the canister 10 does not move due to the rotation of the canister 10 when the shaft rotates. The mechanism for fixing the position of the gap entry device 8 is such that the distance between the inner peripheral surface of the peripheral wall 2a of the main body 2 of the canister inspection device 1 and the holding portion 8a of the gap entry device 8 is variable. As long as the movement of 8 is limited, it is not limited to a specific one. Specifically, for example, one end of a rod-shaped member that passes through the device door 2d and the passage 2e is fixedly attached to the gap entry device 8, and a portion of the rod-shaped member that is exposed to the outside from the device door 2d is an axial center. The structure supported so that reciprocation is possible in a direction is considered.

  Further, the gap approach device 8 may be arranged in the main body 2 before the canister 10 is accommodated in the main body 2 of the canister inspection apparatus 1 or after the canister 10 is accommodated. You may make it throw in.

  When the canister 10 is placed in the main body 2 before the canister 10 is accommodated, the holding portion 8a is pulled through, for example, the apparatus door 2d in a state where the gap approach device 8 is installed on the inner peripheral surface of the main body 2. The urging-side moving mechanism is made to be in the most contracted state, and the canister 10 is accommodated in this state, and then the holding portion 8a is released from being pulled and pressed against the surface of the canister 10. Conceivable.

  Further, when the canister 10 is put into the main body 2 after being accommodated, the gap approach device 8 is thrown into the main body 2 through the device door 2d in a state where the canister 10 is accommodated. Therefore, in this case, the device door 2d is provided as having a size that allows at least the gap entry device 8 to pass therethrough.

  The operation of the above-described canister inspection apparatus 1 when inspecting the canister 10 stored in the concrete container 11 will be described below.

  First, the upper lid 11b of the concrete container 11 is lifted and removed from the main body 11a by a crane or the like.

  Next, the canister inspection device 1 is installed on the upper end of the main body 11a of the concrete container 11 with a crane or the like in a state where the lower surface of the connecting portion 3 is in contact with the upper edge of the peripheral wall of the main body 11a of the concrete container 11. .

  Next, the two doors 4A and 4B of the opening / closing mechanism 4 provided in the connection part 3 move horizontally, and the opening 3a of the connection part 3 is opened (see FIG. 6B).

  Subsequently, the two wire ropes 7 and 7 are sent out by the pair of lifting devices 6 and 6, and the lower ends of the wire ropes 7 and 7 are connected to the canister 10 via the rope connecting portion 10a (FIG. 4). .

  Subsequently, the two wire ropes 7 and 7 are wound up by the pair of lifting devices 6 and 6, and the canister 10 is lifted.

  In this way, the canister inspection apparatus 1 and the concrete container 11 are connected to each other through the internal spaces, whereby the canister 10 is taken out from the concrete container 11 and accommodated in the main body 2 of the canister inspection apparatus 1. When the canister 10 is returned to the concrete container 11 from the main body 2 of the canister inspection apparatus 1, radiation and radiant heat from the canister 10 are prevented from being released to the outside.

  Next, in a state where the canister 10 is accommodated in the main body 2 of the canister inspection apparatus 1, the two doors 4A and 4B of the opening / closing mechanism 4 are moved horizontally, and the opening 3a of the connecting portion 3 is closed (FIG. 5, see FIG. 6 (A)).

  Then, a predetermined inspection is performed on the canister 10 accommodated in the inspection apparatus 1 for the canister. The inspection of the canister 10 may be performed while the canister inspection device 1 is installed on the upper edge of the peripheral wall of the main body 11a of the concrete container 11, or the main body 11a of the concrete container 11 may be inspected. It may be performed in a state where it is lowered from the upper edge of the peripheral wall and placed on the floor surface.

  The inspection of the canister 10 accommodated in the canister inspection apparatus 1 is not limited to a specific type. Specifically, for example, the measurement of the amount of adhered salt or the condition of dew condensation that is a condition for the occurrence of stress corrosion cracking. Check for presence or absence.

  Measurement of the amount of adhered salt on the surface of the canister 10 is a non-contact method using laser-induced breakdown spectroscopy, or the electrical resistance is measured by diluting the salt removed by pressing gauze on the canister surface with water. It is implemented by the method to do.

  The inspection of the presence or absence of condensation on the surface of the canister 10 is performed by a method of confirming by direct visual observation or using a camera.

  As an inspection of the canister 10 accommodated in the canister inspection apparatus 1, there is also a measurement of a crack due to the occurrence of stress corrosion cracking. The measurement can be performed by an eddy current method, an ultrasonic method, or a crack. An electrode is installed so as to straddle, and a method of measuring a crack by utilizing the fact that a potential difference between these electrodes has a correlation with a crack depth is performed.

  In addition, helium gas leakage detection may be mentioned, and the detection is performed by chemical analysis based on gas sampling or a method of measuring and judging a temperature difference between the bottom and top of the canister.

  The canister surface temperature can also be measured by using a non-contact method using a radiation thermometer, a contact method using a thermocouple, or the fact that the birefringence of an optical fiber changes due to heat. It is implemented by a contact method using a fiber Bragg grating.

  And the apparatus door and observation window provided in the peripheral wall 2a and the ceiling part 2b of the main body 2 of the inspection apparatus 1 of the canister, or the peripheral wall 2a, the ceiling part 2b, or the connection part 3 of the main body 2 are provided. The above-described inspection is performed using a gas sampling thin tube or the like.

  At that time, when the rotating device 5 is driven to rotate, the pair of lifting devices 6 and 6 attached to the rotating device 5 swings horizontally, and the pair of lifting devices 6 and 6 move horizontally to move the two wire ropes. 7 and 7, the canister 10 is rotated about the main body 2.

  And, as the canister 10 is pivoted with respect to the main body 2, the device door and the observation window provided on the peripheral wall 2a of the main body 2 are each only one place or the door with the window is only one place. In addition, a predetermined inspection or visual confirmation can be performed over the entire circumference of the side peripheral surface 10b of the canister 10.

  According to the canister inspection method and inspection apparatus configured as described above, the canister 10 can be axially rotated with respect to the main body 2, so that the apparatus door provided for the peripheral wall 2 a of the main body 2 and the observation door Even if there are only one window each or only one door with a window, the entire surface of the side peripheral surface 10b of the canister 10 can be inspected and visually confirmed. For this reason, it is possible to ensure that at least the entire surface of the canister side peripheral surface is inspected to ensure the complete inspection method for the canister, and as a result, the reliability of the inspection results of the canister can be improved. Become. Furthermore, it is possible to reduce labor and time required for the inspection of the entire peripheral surface of the canister.

  According to the canister inspection method and inspection apparatus, the canister 10 can be rotated with respect to the main body 2, so that the inspection related to the soundness of the canister 10 is performed at least over the entire peripheral surface of the canister 10. This makes it possible to streamline operations such as omission of work processes and shortening of inspection time.

  According to the canister inspection method and inspection apparatus, the canister inspection apparatus 1 and the concrete container 11 are connected to each other through the internal spaces, thereby shielding radiation and radiant heat generated from the surface of the canister 10. Since the inspection work can be performed, it is possible to ensure the safety of the worker.

  According to the canister inspection method and inspection apparatus, the canister 10 is pivoted with respect to the main body 2 so that the observation window or the door with the window provided on the peripheral wall 2a of the main body 2 is only one place. However, since visual confirmation can be performed over the entire circumference of the side peripheral surface 10b of the canister 10, radiation and radiant heat emitted to the outside can be reduced.

  Although the above-described embodiment is an example of a preferred embodiment for carrying out the present invention, the embodiment of the present invention is not limited to the above-described embodiment, and the present invention is not deviated from the gist of the present invention. Various modifications can be made. For example, in the above-described embodiment, as shown in FIG. 1, the canister 10 stored in the concrete container 11 moves in the vertical direction in a posture in which the axial center direction is the vertical direction (in other words, the vertical direction). The canister 10 is accommodated in the apparatus 1, but the canister 10 is stored in a posture and moving direction is not limited to this. The canister 10 is stored in a concrete container in a posture in which the axial direction is a horizontal direction. The canister may be moved in the horizontal direction and accommodated in the canister inspection apparatus 1.

  Specifically, as shown in FIG. 9, instead of the two wire ropes 7 and 7 and the pair of lifting devices 6 and 6 constituting the transfer mechanism for transferring the canister 10 into the internal space 2 g of the main body 2. As the transfer mechanism, a single hard rod 12 made of metal, for example, and a shaft driving device 13 that draws and pushes the rod 12 and rotates by the rotating device 5 are used.

  In addition, the canister 10 is placed in the axial direction at a position where the lower end and the upper end of the canister 10 in a posture in which the axial center direction is in the horizontal direction on the inner peripheral surface of the peripheral wall 2a of the main body 2 of the canister inspection apparatus 1 are in contact. A mechanism (specifically, for example, a bearing; reference numeral 14 in FIG. 9) is provided that is movably and rotatably supported (in other words, slidably supported). Further, the canister 10 can be moved in the axial direction at a position where the lower end and the upper end of the canister 10 in a posture in which the axial direction is set to the horizontal direction on the inner peripheral surface of the peripheral wall of the main body 11a of the concrete container 11 are in contact with each other. 9 is provided with a mechanism (specifically, for example, a bearing; reference numeral 11c in FIG. 9) for contact support (slidably supported).

  In addition, even when the canister 10 moves in the vertical direction and is accommodated in the canister inspection apparatus 1 as in the above-described embodiment, a transfer mechanism for transferring the canister 10 into the internal space 2g of the main body 2 is configured. Instead of the wire ropes 7 and 7 and the pair of elevating devices 6 and 6, a single hard rod made of metal, for example, and a shaft driving device that pulls and pushes the rod are used as a transfer mechanism. Anyway.

  In the above-described embodiment, the pair of elevating devices 6 and 6 are swung by the rotating device 5 while the canister 10 is lifted by the pair of elevating devices 6 and 6 and the two wire ropes 7 and 7. The canister 10 is rotated with the wire ropes 7 and 7, that is, the rotating device 5 and the wire rope 7 are used as a rotating mechanism for rotating the canister 10 with respect to the main body 2. The configuration of the rotating mechanism is not limited to this, and a rotating floor plate on which the canister 10 is placed and rotated may be used as the rotating mechanism.

  Specifically, first, the canister inspection apparatus 1 in a state where the canister 10 taken out from the concrete container 11 is accommodated and the opening 3a of the connecting portion 3 is closed by the two doors 4A and 4B of the opening / closing mechanism 4 is provided. It is installed on the upper surface of the rotating floor board 15. Subsequently, as shown in FIG. 10, the two doors 4 </ b> A and 4 </ b> B move horizontally to open the opening 3 a, and the lifting device 6 is operated to place the canister 10 on the upper surface of the rotating floor plate 15. Thereafter, the wire rope 7 is removed from the rope connecting portion 10 a of the canister 10, and the wire rope 7 is wound up so that the tip is separated from the canister 10. And the rotating floor board 15 rotates by the floor board rotating apparatus 16 arrange | positioned under the rotating floor board 15, and, thereby, the canister 10 mounted in the rotating floor board 15 rotates.

  In this case, a thrust bearing 17 is disposed on the upper surface of the rotating floor plate 15 so as to surround the opening 3a of the connecting portion 3 at a position where the connecting portion 3 of the canister inspection apparatus 1 is placed. Further, the canister inspection apparatus 1 is fixed so as not to rotate by an arm or the like (not shown) engaged with the outer peripheral surface of the canister inspection apparatus 1. With such a configuration, the thrust bearing 17 is interposed between the connecting portion 3 of the canister inspection device 1 and the rotary floor plate 15 and the canister inspection device 1 is fixed. Therefore, the canister inspection device 1 is placed. The canister inspection apparatus 1 does not rotate while the rotating floor plate 15 rotates. Further, in order to reduce the emission of radiation to the outside, it is preferable that an annular convex portion 15 a is provided on the peripheral portion of the upper surface of the rotating floor plate 15 so as to surround the thrust bearing 17.

  In the case of the embodiment shown in FIG. 10, instead of the two wire ropes 7 and 7 and the pair of lifting devices 6 and 6 constituting the transfer mechanism for transferring the canister 10 into the internal space 2 g of the main body 2. As the transfer mechanism, a single hard rod made of metal, for example, and a shaft driving device that pulls and pushes out the rod may be used.

  In addition, when the rotating floor board is used as the rotating mechanism, the canister stored in the concrete container moves in the horizontal direction and is accommodated in the canister inspection apparatus 1 in a posture in which the axial direction is the horizontal direction. You may make it apply. In this case, a rod and a shaft driving device are used as the transfer mechanism, and the rotating floor plate 15 is rotated by friction caused by, for example, a circular recess formed in the rotating floor plate 15 and the bottom of the canister 10 being fitted in the recess. Then, the canister 10 is also configured to rotate (however, the mechanism in which the canister 10 rotates when the rotating floor plate 15 rotates is not limited to a mode in which the bottom of the canister 10 is fitted in the recess and uses friction). Absent).

  The canister inspection apparatus 1 may also be used as a canister refill apparatus in a facility that performs spent nuclear fuel storage using a concrete cask method. That is, by configuring the canister refilling device in the spent nuclear fuel storage facility like the canister inspecting device of the present invention, the canister refilling device and the inspecting device can be completed as an integrated device. There is an advantage.

DESCRIPTION OF SYMBOLS 1 Canister inspection apparatus 2 Main body 2a Peripheral wall 2b Ceiling part 2d Device door 2f Observation window 2g Internal space 3 Connection part 3a Opening 4 Opening / closing mechanism 4A, 4B Door 5 Rotating device 6 Lifting device 7 Wire rope

Claims (5)

  A peripheral wall provided with at least one of an apparatus door, an observation window, and a door with a window; a main body having a ceiling portion that closes one end of the peripheral wall; and a canister housed in an internal space; An opening / closing mechanism for closing or opening the opening at the other end of the peripheral wall, a transfer mechanism for transferring a canister stored in a storage container for storing the canister into the internal space of the main body, and A canister inspecting device having a rotating mechanism for rotating the canister in the internal space of the main body with respect to the main body in contact with the storage container. The opening is opened, the canister stored in the storage container is transferred into the internal space of the main body by the transfer mechanism, and the opening / closing mechanism is used to transfer the canister. The device door, the observation window, and the window door provided on the main body while the canister is axially rotated with respect to the main body by the rotation mechanism after closing the opening at the other end of the wall. A canister inspection method, wherein the canister is inspected using at least one of the above.   A holding unit that holds a probe, and an object that is provided on the canister side of the holding unit and that can move the holding unit relative to the canister while maintaining a constant distance between the canister and the holding unit The object-side moving mechanism and the holding unit provided on the opposite side of the holding unit to the canister, while urging the holding unit in a direction in which the holding unit is pressed against the canister, An apparatus having an urging-side moving mechanism capable of moving the device is inserted between an inner peripheral surface of the peripheral wall of the main body and a side peripheral surface of the canister, and the canister is inspected. Item 2. A method for inspecting a canister according to item 1.   A peripheral wall provided with at least one of an apparatus door, an observation window, and a door with a window; a main body having a ceiling portion that closes one end of the peripheral wall; and a canister housed in an internal space; An opening / closing mechanism for closing or opening the opening at the other end of the peripheral wall, a transfer mechanism for transferring a canister stored in a storage container for storing the canister into the internal space of the main body, and A canister inspection apparatus comprising: a rotation mechanism that rotates a canister in the internal space of a main body with respect to the main body.   A holding unit that holds a probe, and an object that is provided on the canister side of the holding unit and that can move the holding unit relative to the canister while maintaining a constant distance between the canister and the holding unit The object-side moving mechanism and the holding unit provided on the opposite side of the holding unit to the canister, while urging the holding unit in a direction in which the holding unit is pressed against the canister side, with respect to the structure on the opposite side of the canister 4. A canister inspection according to claim 3, wherein a device having an urging-side moving mechanism capable of moving the device is inserted between an inner peripheral surface of the peripheral wall of the main body and a side peripheral surface of the canister. apparatus.   5. The canister inspection apparatus according to claim 3, wherein the canister inspection apparatus is also used as a canister refilling apparatus in a facility for storing spent nuclear fuel of a concrete cask type.

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