JP2017211188A - Cask facility and cask handling method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cask facility which is simpler and more inexpensive than a conventional one.SOLUTION: A cask facility 100 includes: a rail 2 which extends in a horizontal direction, and which is installed in such a manner that a horizontal cask C storing spent fuel can be moved in the horizontal direction; a hoisting device 30 which is installed above the rail 2, and which includes a wire 32 for engaging with one end of the horizontal cask C positioned at a suspending position P2 on the rail 2, so as to hoist up the cask C; and a horizontal movement part 40 for applying force to the cask C toward the one end, so as to move the cask C on the rail 2.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a cask facility and a cask handling method.

  Spent nuclear fuel generated at a nuclear power plant is stored for a period of time in a storage pool within the power plant for cooling. Thereafter, it is sent to a reprocessing plant for processing or stored for a long time in a radioactive waste disposal site.

  However, if there is no space in the storage pool, spent nuclear fuel may be temporarily stored at an intermediate storage facility near the storage pool. When transporting and storing spent nuclear fuel to such facilities, a container called a cask is used. The cask has a cylindrical shape made of concrete or steel, and spent nuclear fuel is enclosed in the inside together with an inert gas such as helium having high thermal conductivity.

At the time of transportation, in view of easiness of cargo handling and the like, it is common to place the cask in a horizontally placed state (that is, a state in which the central axis of the cylindrical cask is directed in the horizontal direction). On the other hand, at the time of storage in an intermediate storage facility, the cask may be in an upright state (that is, a state where the central axis of the cask is directed in the vertical direction) mainly in consideration of stability in the event of an earthquake. That is, when carrying the cask into the intermediate storage facility, a work (handling work) for changing the posture of each cask is required. As a specific example of such handling work, a method described in Patent Document 1 below is known. Patent Document 1 describes a method of handling a cask (storage container) not in a storage facility but in a nuclear reactor. In this method, one end of the cask is lifted upward by the heavy equipment placed on the temporary floor in the nuclear reactor, so that the cask is changed from the horizontal position to the upright state.
On the other hand, when performing the same work not in the nuclear reactor but in the above-mentioned intermediate storage facility, it is common in the past to use a crane (hoist) permanently installed on the ceiling of the facility (building) (note that The crane as used herein refers to a mechanical device that can be moved in a horizontal direction with a load suspended.)

Japanese Patent No. 4095879

  However, such cranes as described above are generally expensive, which has been one of the causes of an increase in the construction cost of storage facilities. In addition, since the handling of cask itself does not involve a large horizontal movement, the above cranes are not necessarily the best equipment, and there is room for replacement with simpler and less expensive equipment. there were.

  The present invention has been made to solve the above-described problems, and it is an object of the present invention to provide a simpler and less expensive cask facility and a cask handling method.

  The facility for cask according to the first aspect of the present invention includes a rail that extends in the horizontal direction and is installed so that a cask containing spent fuel can be moved in the horizontal direction in a horizontal state, and above the rail. A hoisting device having a wire or the like which is installed and engages with one end side of the cask in a horizontal state located at the hoisting position on the rail and hoists upward; and one end with respect to the cask on the rail A horizontal movement unit that moves the cask by applying a force toward the side.

According to this configuration, the one end side of the cask is lifted upward by the hoisting device, and a force is applied to the cask toward the one end side by the horizontal movement unit. Therefore, for example, compared with a configuration in which only one end side of the cask is lifted, the cask can be changed from the horizontally placed state to the upright state more smoothly and stably.
Furthermore, in the above configuration, a cask facility can be configured without using expensive equipment such as a crane. That is, the construction cost of the cask facility can be reduced.

  In the cask facility according to the second aspect of the present invention, the horizontal movement unit may include a pulling wire that engages with the other end side of the cask and pulls the cask toward the one end side.

  According to this configuration, the cask can be handled only by pulling the pulling wire toward one end side. That is, the configuration of the apparatus can be made simpler than the configuration in which the other end side of the cask is horizontally moved by a crane or the like. Thereby, the construction cost of the facility for cask can be further reduced.

  The facility for cask according to the third aspect of the present invention may have a leg portion that is provided on the floor and supports the hoisting device upward.

  According to this configuration, the hoisting device is supported upward by the legs. Thereby, compared with the case where the winding apparatus is installed in the ceiling of a building, for example, the strength design of the building itself can be given a degree of freedom. In other words, the design cost and material cost for increasing the structural strength of the building can be reduced.

  In the cask handling method according to the fourth aspect of the present invention, the one end of the horizontally placed cask is pulled upward, and a force is applied toward the one end with respect to the other end of the cask. A handling step of erecting the cask.

  According to this method, the one end side of the cask is lifted upward, and a force is applied to the cask toward the one end side. Therefore, for example, the cask can be changed from the horizontally placed state to the upright state more smoothly and stably than the method in which only one end side of the cask is lifted.

  According to the present invention, a simple and inexpensive cask facility and a cask handling method can be provided.

It is a general view which shows the structure of the cask facility which concerns on embodiment of this invention, Comprising: The state immediately after carrying in a cask is represented. It is a perspective view which shows the structure of the cask transporter which concerns on embodiment of this invention. It is a general view which shows the structure of the facility for cask which concerns on embodiment of this invention, Comprising: The mode that the cask is handled is represented. It is process drawing of the handling method of the cask which concerns on embodiment of this invention.

  Embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 1, the cask facility 100 according to the present embodiment is classified as a dry storage facility. The cask C contained in the cask C is removed from the heat generated by the natural ventilation, and the radiation in the event of an emergency. The purpose is to prevent external leakage. Specifically, the cask facility 100 includes a building 1, a pair of rails 2 laid on the floor surface F of the building 1, and a handling device 3 arranged so as to straddle the rails 2.

  The building 1 is a ground structure that houses a plurality of casks C in which spent nuclear fuel is stored. The building 1 is provided with an air supply unit 10 for taking in external air and an exhaust unit 11 for exhausting the internal air to the outside. Further, the building 1 is provided with an entrance 12 through which a vehicle V transporting the cask C (cask transport body Ct) enters and exits.

  The rail 2 supports the cask C so as to be movable in the horizontal direction. Specifically, the rail 2 extends linearly from the position on the entrance / exit 12 side (mounting position P1) to the position where the cask C is lifted (lifting position P2). A pair of rails 2 is provided on the floor surface F of the building 1 with a space in the horizontal direction. The distance between the rails 2 is set larger than the vehicle width of the vehicle V described above. As a result, the vehicle V can move forward and backward in the space between the rails 2. Further, the height of the rail 2 from the floor surface F is the same as or slightly lower than the height position of the cask transporter Ct mounted on the vehicle V.

  As shown in FIG. 1 again, the handling device 3 is a device for changing the posture of the cask transporter Ct placed on the rail 2. More specifically, the handling device 3 includes a winding device 30 and a winch 40 (horizontal movement unit). The hoisting device 30 is supported above the inside of the building 1 by legs L arranged on the floor surface F of the building 1 so as to straddle the rail 2.

  The hoisting device 30 includes a reel 31 that rotates about a rotation axis that extends in the horizontal direction, and a wire 32 (hanging material) wound around the reel 31. The reel 31 is rotated by a drive source (not shown) to unwind or wind the wire 32. The wire 32 is suspended from the reel 31 vertically downward. Further, an engaging portion 33 that engages with a part of the cask C is provided at the tip (lower end) of the wire 32. The wires 32 (and the engaging portions 33) are provided in pairs in the horizontal direction (in the direction in which the rails 2 are arranged) with a gap therebetween. That is, each engaging portion 33 is engaged with a pair of upper trunnions C31 described later. (In FIG. 1, one wire 32 and one engagement portion 33 are shown for convenience.)

  The winch 40 is disposed on the floor surface F at a position opposite to the doorway 12 with the rail 2 interposed therebetween. The winch 40 includes a reel 41 and a pulling wire 42 wound around the reel 41. The winch 40 unwinds or winds the pulling wire 42 by rotating the reel 41, similarly to the winding device 30. An engaging portion 43 that is engaged with a part of a transport skid St described later is provided at the tip of the pulling wire 42. The pulling wires 42 (and the engaging portions 43) are provided in pairs in the horizontal direction (in the direction in which the rails 2 are arranged) with a gap therebetween. That is, the respective engaging portions 43 are engaged with side surfaces on both sides in the horizontal direction of a transport skid St described later. (In FIG. 1, one pulling wire 42 and one engaging portion 43 are shown for simplicity.)

  Next, the structure of the cask C (cask transport body Ct) will be described with reference to FIG. In addition, the cask transport body Ct mentioned here refers to the cask C in a state of being loaded to be transported by the vehicle V or the like. Specifically, the cask transporter Ct has a cask C and a transport skid St attached to the cask C.

  The cask C is a metal (steel) container having a cylindrical shape. The inside of the cask C is a cavity, and spent nuclear fuel is accommodated therein, for example, in the form of fuel rods (or pellets). Specifically, the cask C has a cylindrical main body C1 extending along the central axis A, and disk-shaped lids C2 attached to both ends of the main body C1. The lid C2 is closely attached and fixed to the main body C1 via a gasket (not shown). The main body C1 is provided with a plurality of trunnions C3 for attaching a transport skid St described later.

  Each trunnion C3 has a cylindrical shape protruding from the outer peripheral surface of the main body C1 toward the radially outer side of the central axis A. The cask C in this embodiment is provided with a total of eight such trunnions C3, but the number of trunnions C3 is not limited to this, and at least four or more trunnions C3 are provided. That's fine. More specifically, four upper trunnions C31 are provided at equal intervals in the circumferential direction on one end side in the central axis A direction of the main body C1, and at the other end side in the central axis A direction at equal intervals in the circumferential direction. Four lower trunnions C32 are provided. Here, “upper” and “lower” refer to an upper side and a lower side in a state where the cask C stands upright (upright state), respectively.

  Although not shown in detail, the main body C1 has a multilayer structure from the inside to the outside. Thereby, the radiation emitted from the spent nuclear fuel is shielded and the heat can be dissipated to the outside.

  In the following description, the “upright state” and the “horizontal state” are used as expressions indicating the posture of the cask C. The upright state indicates a state in which the cask C is placed with the central axis A directed in the vertical direction, and the horizontal state indicates a state in which the cask C is placed with the central axis A directed in the horizontal direction. Indicates.

  The cask C configured in this manner is placed on the transport skid St in a horizontal state when transported by the vehicle V or the like. The transport skid St is a saucer-like jig for supporting the main body C1 of the cask C from below. Specifically, the transport skid St includes a rectangular bottom portion 51 and four support portions 52 that protrude upward from the four corners of the bottom portion 51. An engaging recess R that engages with the trunnion C3 of the cask C is formed at the upper end of each support portion 52. The engaging recess R is recessed downward from the upper end surface of the support portion 52 and has a semicircular cross section when viewed in the horizontal direction. The diameter dimension of the engaging recess R is set to be the same as or slightly larger than the outer dimension of the trunnion C3 having a cylindrical shape.

  Furthermore, when carrying in the building 1, the extension skid Se (skid) is attached to this transport skid St. The extension skid Se is a device for smoothly moving the cask transporter Ct on the rail 2 in the building 1. Specifically, the extension skid Se includes a plurality of rollers 61 that roll on the rail 2 along the rail 2, a roller support portion 62 that rotatably supports these rollers 61, and an upper side of the roller support portion 62. And a contact portion 63 that contacts the transport skid St (bottom portion 51) from the horizontal direction. Such an extension skid Se is attached so as to protrude from the support portions 52 of the transport skid St onto the rails 2 toward both sides in the horizontal direction. In attaching the extension skid Se, the height of the vehicle V is changed while the cask transport body Ct is mounted on the vehicle V, so that the rail 2 and the transport skid St (bottom 51) A method of providing a gap between them and inserting the extension skid Se into the gap is conceivable. In other words, it is desirable that the vehicle V can freely adjust the vehicle height in this way.

  Next, a method for housing the cask transporter Ct (a method for handling the cask C) will be described with reference to FIGS. 1, 3, and 4. The method for housing the cask transporter Ct includes a carry-in process S1, a receiving process S2, a balling process S3, a handling process S4, and a transfer process S5.

  First, as shown in FIG. 1, the cask transporter Ct loaded in advance at a nuclear power plant or the like is carried into the building 1 by a vehicle V (carrying-in process S1). At this time, in addition to the above-described transport skid St, a disc-shaped buffer body 70 made of wood such as balsa may be attached to the cask transporter Ct. Specifically, one shock absorber 70 is attached to each side of the cask C in the direction of the central axis A. In carrying the cask transporter Ct, specifically, the vehicle V is caused to enter the space between the rails 2. Thereafter, the extension skid Se is attached to the transport skid St while raising the vehicle height of the vehicle V by jacking up or the like. Next, the vehicle V is jacked down and the roller 61 of the extension skid Se is placed on the mounting position P1 on the rail 2. Thereby, the carrying-in process S1 is completed. In addition, the vehicle V which became empty leaves the exterior from the entrance / exit 12.

  For the cask transporter Ct carried into the building 1, an acceptance inspection for confirming the state of the cask C and the work for removing the buffer body 70 are performed (accepting step S <b> 2). Next, the wire 32 of the hoisting device 30 and the pulling wire 42 of the winch 40 are attached to the cask transporter Ct (balling step S3). Specifically, each engaging portion 33 provided at the tip of each wire 32 is attached to a pair of upper trunnions C31 facing the horizontal direction among the upper trunnions C31. Further, the respective engaging portions 43 provided at the distal ends of the pulling wires 42 are attached to a part of the transport skid St (side surfaces facing both sides in the horizontal direction).

  Subsequently, the cask C is taken out from the cask transporter Ct, and the posture of the cask C is changed (handling step S4). More specifically, as shown in FIG. 3, first, the cask transporter Ct is moved along the rail 2 from the mounting position P1 to the lifting position P2 by winding only the pulling wire 42 of the winch 40. . After the cask transport body Ct reaches the lifting position P2, the winding of the wire 32 by the winding device 30 and the winding of the pulling wire 42 by the winch 40 are performed in a synchronized state. That is, the winding of the wire 32 and the winding of the pulling wire 42 are started at the same time and proceed at the same speed. In actual work, it is desirable to manually synchronize the winding of the wire 32 and the pulling wire 42 under the supervision of the worker. On the other hand, it is also possible to adopt a configuration in which these winding operations are synchronized by a control device or the like.

  As the winding up of the wire 32 proceeds, one end side of the cask C gradually moves upward as shown by the chain line in FIG. At the same time, as the pulling wire 42 is wound up to the other end, a force directed from the other end to the one end is applied to the cask C. Here, since the cask C is placed on the transport skid St and the extension skid Se, the portion including the other end side of the cask C is on the rail 2 by the pulling force of the pulling wire 42. It moves horizontally from the other end side to the one end side. More specifically, the roller 61 of the extension skid Se rolls on the rail 2 so that the other end side of the cask C moves toward one end side. By continuing such an operation, the cask C shifts from the horizontal position to the upright position on the transport skid St. At this time, the pair of lower trunnions C32 (the pair of lower trunnions C32 facing in the horizontal direction) engaged with the engagement recess R of the transport skid St has a line connecting the lower trunnions C32 in the engagement recess R. It rotates gradually as the center of rotation. After the cask C stands upright, the cask C is further lifted upward by the winding device, so that the cask C is detached from the transport skid St.

  With the cask C detached from the transport skid St, the transport skid St is removed from the lifting position P2 on the rail 2. Thereafter, an air pallet (not shown) is inserted between the suspended cask C and the floor surface F. Finally, the upright cask C placed on the air pallet is transferred to a predetermined storage position (transfer step S5). As described above, all the steps of the method for housing the cask transporter Ct (the method for handling the cask C) according to the present embodiment are completed.

  As described above, in the cask facility 100 according to the present embodiment, the one end side of the cask C is lifted upward by the hoisting device 30 and a force toward the one end side is applied to the cask C by the pulling wire 42 of the winch 40. Is done. Therefore, for example, compared with a configuration in which only one end side of the cask C is lifted, the cask C can be changed from the horizontal position to the upright state more smoothly and stably. Furthermore, the cask facility 100 can be configured without providing expensive equipment such as cranes in the building 1. That is, the construction cost of the cask facility 100 can be reduced.

  In addition, the crane said here points out the mechanical apparatus which can be moved to a horizontal direction in the state which suspended the load. Since cranes are generally expensive, they have been one of the causes of increased construction costs for storage facilities. In addition, since the handling (cause) of the cask C itself does not involve a large horizontal movement, the crane as described above is not necessarily the optimum equipment, and there is room for replacement with simpler and less expensive equipment. There is also. Therefore, in the present embodiment, the above-described winding device and winch 40 are provided in place of the crane, so that the simplification and cost reduction of the facility can be easily realized.

  Further, according to the above configuration, the cask C can be handled only by pulling the pulling wire 42 toward the one end side by the winch 40. That is, the configuration of the horizontal moving unit can be made simpler than the configuration in which the other end side of the cask C is horizontally moved by a crane or the like. Thereby, the construction cost of the cask facility 100 can be further reduced.

  In addition, according to the above configuration, the hoisting device 30 is supported above by the leg portion L. Thereby, compared with the case where the hoisting device 30 is installed in the ceiling of the building 1, for example, the strength design of the building 1 itself can be given a degree of freedom. In other words, the design cost and material cost for increasing the structural strength of the building 1 can be reduced. Thus, according to the configuration of the present embodiment, the structure of the cask facility 100 can be simplified, and the cost required for construction can be reduced.

  The embodiment of the present invention has been described above. Various modifications can be made to the above configuration without departing from the gist of the present invention.

  For example, instead of the winch 40 in the above-described embodiment, another device that pushes the cask C from the other end side to the one end side can be employed as the horizontal moving unit. In other words, any device may be applied as the horizontal movement unit as long as a force from the other end side toward the one end side can be applied to the other end of the cask C via the lower trunnion C32.

  Furthermore, in the above embodiment, a dry storage facility is taken as an example of the cask facility 100, but the cask facility 100 may be a wet storage facility.

  In addition, in the above configuration, an example in which the placement position P1 and the lifting position P2 are separately provided on the rail 2 has been described. That is, in the said embodiment, after the cask transport body Ct is first mounted in the mounting position P1 by the vehicle V, the structure which moves to the lifting position P2 is taken. However, it is not always necessary to provide the placement position P1 depending on the space or the like, and it is possible to adopt a configuration in which the vehicle V directly places the cask transporter Ct at the lifting position P2.

  In addition, although the winding device and the winch 40 described above have been described with respect to the example having the wire 32 (the pulling wire 42), a chain or a rope is used instead of the wire 32 and the pulling wire 42. Is also possible. In short, any suspension material that has tensile strength that can accommodate the weight of the cask C and that can be freely deformed (wound and unwound) can be suitably applied as a suspension material. Is possible. In addition, as the winding device 30, it is also possible to use a jack capable of pulling the wire 32 instead of the configuration including the reel 31 described in the above embodiment.

  Moreover, the said embodiment demonstrated the example in which the building 1 was provided on the ground. However, depending on the surrounding environment and the like, the building 1 may have a configuration in which the entire building is buried underground, or only a part of the building 1 is buried underground and the remaining portion is exposed to the ground. May be taken.

  Furthermore, in the said embodiment, when moving the cask C (cask transport body Ct) in the building 1, the example using the extension skid Se was demonstrated. However, as long as the cask transporter Ct can be smoothly moved on at least the rail 2, it is possible to adopt a configuration in which the extension skid Se is not used.

  In addition, in the above-described embodiment, an example in which the removal work of the buffer body 70 is performed in the receiving step S2 has been described. However, the removal work of the buffer body 70 is not necessarily performed in the receiving step S2, and can be appropriately performed in another step (for example, the above-described loading step S1).

DESCRIPTION OF SYMBOLS 1 ... Building 2 ... Rail 3 ... Handling apparatus 10 ... Air supply part 11 ... Exhaust part 12 ... Entrance / exit 30 ... Winding device 31 ... Reel 32 ... Wire (suspending material)
33 ... engaging part 40 ... winch 41 ... reel 42 ... pulling wire 43 ... engaging part 51 ... bottom part 52 ... support part 61 ... roller 62 ... roller support part 63 ... contact part 70 ... buffer 100 ... facility for cask A ... Center axis C ... Cask C1 ... Main body C2 ... Lid C3 ... Trunnion C31 ... Upper trunnion C32 ... Lower trunnion Ct ... Cask transporter F ... Floor L ... Leg P1 ... Mounting position P2 ... Lifting position R ... Engaging recess S1 ... loading process S2 ... receiving process S3 ... balling process S4 ... handling process S5 ... transfer process Se ... extension skid St ... transport skid V ... vehicle

Claims (4)

A rail that extends in the horizontal direction and is movably installed in the horizontal direction in a state in which a cask containing spent fuel is placed horizontally;
A hoisting device installed above the rail and having a hoisting material that engages with one end side of the cask in a horizontally placed state located at the hoisting position on the rail and winds up the cask.
A horizontal movement unit that moves the cask by applying a force toward the one end side of the cask on the rail;
A facility for cask with.   2. The cask facility according to claim 1, wherein the horizontal moving unit includes a tension suspension member that engages with the other end side of the cask and pulls the cask toward the one end side.   The cask facility according to claim 1, further comprising a leg portion provided on a floor surface and supporting the hoisting device upward.   A method for handling a cask, comprising a handling step of raising the one end side of the cask upward and applying a force toward the other end side of the cask toward the one end side so as to erect the cask.

Images