JP6985188B2 - Heat transfer test equipment for containers used to transport and / or store spent fuel - Google Patents

Description

The present invention relates to a test device for confirming the performance required for a container used for transporting and / or storing spent fuel taken out from a nuclear reactor, and more specifically, heat transfer for confirming the heat transfer function of the container. The present invention relates to a heat transfer test device used for the test.

Containers (hereinafter referred to as casks) used for transporting and / or storing spent fuel taken out of a nuclear reactor are known. The spent fuel contained in the cask generates heat of up to several tens of kW per cask and emits a considerable amount of gamma rays and neutrons. Therefore, the cask is required to have a high safety function.

Safety functions include heat removal function, sealing function, shielding function and criticality prevention function. The heat removal function is a function that dissipates the heat of the spent fuel and appropriately lowers the temperature of the components of the cask and the used fuel. The sealing function is a function of trapping spent fuel as a radioactive substance in the cask. The shielding function is a function that shields gamma rays and neutrons emitted from spent fuel, lowers the dose rate outside the cask, and prevents radiation exposure. The criticality prevention function is a function of preventing the criticality of uranium-235 remaining in the spent fuel due to nuclear fission.

The safety features required of a cask need to be verified before the cask is actually used. Among the safety functions required for the cask, a heat transfer test is performed for the heat removal performance.

In the heat transfer test, for example, as described in Non-Patent Documents 1 and 2 below, a heater that generates heat corresponding to the calorific value of the spent fuel is partitioned by a grid-like basket arranged in the cask body. It is inserted into each of the plurality of accommodation spaces, and the internal surface temperature of the cask body and the basket is measured by a thermocouple, and it is confirmed that the temperature does not exceed the temperature determined by the analysis at the time of design.

Mitsubishi Heavy Industries Technical Report Vol. 35 No. 4 pp. 286-289 Hitachi Review Vol. 86 No. 2 pp. 209-212

In the heat transfer test described in Non-Patent Documents 1 and 2, as a preparatory work, a thermocouple as a temperature measuring device for measuring the surface temperature of the inner surface of the cask body or the basket is used, and the surface temperature on the inner surface of the cask body or the basket is used. It is necessary to hold the thermocouple in a measurable position (specifically, to fix the thermocouple to the inner surface of the cask body or basket).

Here, since each of the plurality of storage spaces partitioned by the grid-like baskets may be large enough to store spent fuel, a thermocouple is placed on the inner surface of the basket when the basket has been assembled. If it is attempted to be fixed, it may be out of the reach of the operator and it may be difficult to fix the thermocouple in a desired position. Therefore, in order to fix the thermocouple to the inner surface of the basket, it is necessary to fix the thermocouple while assembling the basket. As a result, it is necessary to assemble the basket while avoiding the lead wire of the thermocouple, which causes a problem that the work efficiency is lowered.

In addition, when inserting the basket into the container body, it is necessary to prevent the thermocouple from coming off. Therefore, the work of inserting the basket into the container body must be carefully performed, and there is a problem that the work efficiency is lowered.

That is, in the heat transfer test described in Non-Patent Documents 1 and 2, the heat transfer test is efficiently performed because the work of holding the thermocouple at a position where the surface temperature can be measured on the inner surface of the cask body or the basket is inefficient. Difficult to do.

An object of the present invention is to improve the efficiency of the work of holding the temperature measuring instrument at a position where the surface temperature of the inner surface of the container body or the basket needs to be measured in the preparatory work of the heat transfer test, thereby making the heat transfer test more efficient. It is to provide a heat transfer test device that can be performed well.

The heat transfer test apparatus according to the present invention transports and / or transports the used fuel in a state where the used fuel is stored in each of a plurality of storage spaces defined by a grid-like basket and extending in a predetermined direction in parallel with each other. A container body used for storage and having an opening for inserting the basket from the outside to accommodate the basket and a container lid attached to the container body so as to cover the opening of the container body. A heat transfer test device used for a heat transfer test for confirming the heat removal function of a container containing a container, which is a temporary lid that can be attached to the container body instead of the container lid, and an inner surface of the container body or the basket. When the temporary lid is lowered toward the container body from above the container body in a state where each of the plurality of accommodation spaces is open upward and a temperature measuring device capable of measuring the surface temperature on the inner surface. By moving together with the temporary lid while supporting the temperature measuring device, the container is connected to the temporary lid so as to be inserted into the container body together with the temperature measuring device, and the temperature is measured at a position where the surface temperature can be measured. It is equipped with a holding mechanism for holding the container.

In the heat transfer test apparatus, the temperature measuring device can be inserted into the container body in which the basket is housed by lowering the temporary lid from above the container body toward the container body. Further, with the temperature measuring device inserted in the container body in which the basket is housed, the temperature measuring device can be held at a position where the surface temperature on the inner surface of the container body or the inner surface of the basket can be measured. Therefore, it is not necessary to fix the temperature measuring device while assembling the basket, or to insert the basket to which the temperature measuring device is fixed into the container body. As a result, the work of holding the temperature measuring device at a position where the surface temperature on the inner surface of the container body or the inner surface of the basket can be measured can be efficiently performed. Therefore, in the above heat transfer test apparatus, the time required for preparation for the heat transfer test can be shortened, and the heat transfer test can be efficiently performed.

In the heat transfer test apparatus, preferably, the temperature measuring device can directly or indirectly contact the inner surface of the basket, and the basket is in direct or indirect contact with the inner surface of the basket. A contact-type temperature measuring device that includes a terminal portion that allows heat transfer from the inner surface of the basket and measures the surface temperature on the inner surface of the basket in a state where the terminal portion is in direct or indirect contact with the inner surface of the basket. The holding mechanism includes an operated portion that can be operated from the outside of the container body with the temporary lid attached, and the terminal portion is a retracted position in the container body that is separated from the inner surface of the basket. The terminal portion is held so as to be movable between the terminal portion and the contact position in direct or indirect contact with the inner surface of the basket, and the terminal portion is moved to the terminal portion in conjunction with an operation on the operated portion. Move between the retracted position and the contact position.

In the above heat transfer test device, even when a contact type temperature measuring device is adopted, the temperature measuring device can be moved to a position where the surface temperature can be measured without contacting the container body and the basket. can.

In the heat transfer test apparatus, preferably, the holding mechanism is movably arranged together with the terminal portion while supporting the terminal portion, and the basket is provided with the terminal portion in a state where the terminal portion is located at the contact position. Includes contact members that come into contact with the inner surface of the.

In the above heat transfer test device, when the terminal portion is brought into contact with the inner surface of the basket, not only the terminal portion but also the contact member supporting the terminal portion is brought into contact with the inner surface of the basket, so that the terminal portion contacts the inner surface of the basket. The state can be stabilized.

In the heat transfer test apparatus, preferably, the holding mechanism is arranged so as to be movable together with the terminal portion while supporting the terminal portion, and includes a contact member that can contact the inner surface of the basket, and the terminal portion includes the terminal portion. The surface temperature on the inner surface of the basket is measured by indirectly contacting the inner surface of the basket through the contact member that is in contact with the inner surface of the basket.

In the above heat transfer test device, since the terminal portion contacts the inner surface of the basket via the contact member, the contact state of the terminal portion with respect to the inner surface of the basket can be stabilized.

In the heat transfer test apparatus, preferably, the holding mechanism is further suspended from the temporary lid and is arranged between a frame that supports the contact member and the contact member and the frame, and the terminal portion. The terminal portion is attached to the terminal portion in conjunction with a spring that applies an elastic force, which is an urging force in a direction of moving from the retracted position to the contact position, to the contact member and a first operation on the operated portion. The terminal portion is moved from the contact position toward the retracted position against the force, and the terminal portion is moved from the retracted position toward the contact position by the urging force in conjunction with the second operation with respect to the operated portion. Including a moving mechanism to make it.

In the above heat transfer test apparatus, even when the distance from the frame to the inner surface of the basket varies, the elastic force of the spring can ensure that the contact member is brought into contact with the inner surface of the basket. Therefore, the contact state of the terminal portion with respect to the inner surface of the basket can be stabilized.

In the heat transfer test apparatus, preferably, the moving mechanism is connected to a wire whose one end is connected to the contact member and the other end of the wire, and moves with the first operation on the operated portion. As a result, a tensile force is applied to the wire so as to move the terminal portion from the contact position toward the retracted position against the urging force, and the terminal portion moves with the second operation on the operated portion. Thereby, the connection portion that releases the tensile force and moves the terminal portion from the retracted position to the contact position by the urging force, and the terminal portion in the direction in which the urging force acts on the contact member. Includes a guide portion that guides the wire so that the wire moves from the retracted position toward the contact position.

In the above heat transfer test device, the contact state and the non-contact state of the terminal portion with respect to the inner surface of the basket are switched by a mechanical operation using a wire, so that compared with the case of using a mechanism driven by an electric signal, for example. Therefore, it is possible to improve the reliability of the operation of bringing the terminal portion into contact with the inner surface of the basket.

In the heat transfer test apparatus, preferably, the contact members are arranged on both sides of the frame in a direction perpendicular to the direction in which the temporary lid is lowered from above the container body toward the container body.

In the heat transfer test apparatus, the contact member can be brought into contact with the inner surface of the basket by stretching the frames on both sides. As a result, the contact state of the contact member with respect to the inner surface of the basket can be further stabilized.

In the heat transfer test device, an image pickup device capable of photographing a state in which the contact member is inserted into the container body through a through hole formed in the temporary lid and the contact member is in contact with the inner surface of the basket is further provided. Be prepared.

In the above heat transfer test apparatus, the state in which the contact member is in contact with the inner surface of the basket can be confirmed from the outside of the container body.

According to the heat transfer test apparatus according to the present invention, the heat transfer test can be efficiently prepared, so that the heat transfer test can be efficiently performed.

It is a schematic diagram which shows the schematic structure of the heat transfer test apparatus by embodiment of this invention. FIG. 3 is a cross-sectional view taken along the line AA in FIG. It is sectional drawing of BB in FIG. FIG. 3 is a sectional view taken along the line CC in FIG. It is a perspective view which shows the schematic structure of the temperature measuring apparatus included in the heat transfer test apparatus shown in FIG. It is a drawing which shows the part of FIG. 1 enlarged. It is a drawing which shows the other part of FIG. 1 enlarged. It is a side view which shows the modification of the holding mechanism provided in the temperature measuring device. It is a top view which shows the modification of the holding mechanism provided in the temperature measuring apparatus, and is the top view which shows the state which the thermocouple is not fixed to the inner surface of a basket. It is a top view which shows the modification of the holding mechanism provided in the temperature measuring apparatus, and is the top view which shows the state which the thermocouple is fixed to the inner surface of a basket.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The heat transfer test apparatus 10 according to the embodiment of the present invention will be described with reference to FIGS. 1, 2, 3 and 4. FIG. 1 is a schematic diagram showing a schematic configuration of the heat transfer test apparatus 10. FIG. 2 is a cross-sectional view taken along the line AA in FIG. FIG. 3 is a cross-sectional view taken along the line BB in FIG. FIG. 4 is a cross-sectional view taken along the line CC in FIG.

The heat transfer test device 10 is used for a heat transfer test for confirming the heat transfer function of the cask. The cask is a container used for transporting and / or storing used fuel, and includes a container body for accommodating the basket 60 and a container lid for covering the opening of the container body.

Here, as shown in FIGS. 2, 3 and 4, the basket 60 is formed by combining a plurality of first plates 62 and a plurality of second plates 64 in a grid pattern. A plurality of storage spaces 66 are formed in the basket 60. The plurality of accommodation spaces 66 extend in a predetermined direction in a state parallel to each other. Each opening of the plurality of accommodation spaces 66 has a rectangular shape.

The heat transfer test device 10 includes a temporary lid 20, a plurality of simulated heat sources 30, a plurality of connecting mechanisms 40, and a temperature measuring device 50. These will be described below.

The temporary lid 20 is attached to the container body instead of the container lid during the heat transfer test. That is, the temporary lid 20 is removable from the container body. The temporary lid 20 has the same sealing performance as the container lid. The temporary lid 20 has the same heat transfer performance as the container lid.

Each of the plurality of simulated heat sources 30 is heated to a temperature simulating the calorific value of the spent fuel. The plurality of simulated heat sources 30 are accommodated one by one in each of the plurality of accommodation spaces 66.

The plurality of simulated heat sources 30 include two support plates 31, 33, a plurality of heat control plates 32, and a plurality of heater wires 34, respectively.

The two support plates 31 and 33 are arranged apart from each other in the direction in which the accommodation space 66 extends (vertical direction in FIG. 1). The two support plates 31 and 33 have the same shape and size as each other. In the present embodiment, the two support plates 31 and 33 each have a rectangular plate shape having a size slightly smaller than the opening of the accommodation space 66.

The plurality of heat regulating plates 32 are located between the pair of support plates 31 in the direction in which the accommodation space 66 extends. The plurality of heat regulating plates 32 have the same shape and size as each other. In the present embodiment, the heat regulating plate 32 has a rectangular plate shape having a size one size smaller than the opening of the accommodation space 66. The heat regulating plate 32 has the same shape and size as the support plate 31.

Each of the plurality of heater wires 34 extends in the direction in which the accommodation space 66 extends. Each of the plurality of heater wires 34 is arranged so as to penetrate the plurality of heat regulating plates 32. One end of each of the plurality of heater wires 34 is supported by a support plate 31. The other end of each of the plurality of heater wires 34 is supported by the support plate 33. Each of the plurality of heater wires 34 has a plurality of heat generating regions 341. The plurality of heat generating regions 341 are formed side by side in the direction in which the heater wires 34 extend. The calorific value of the plurality of heat generating regions 341 is different from each other. As a method of making the heat generation amount of the plurality of heat generation regions 341 different from each other, for example, there are a method of making the number of turns of the conducting wire different for each heat generation region 341, a method of making the power supplied for each heat generation region 341 different, and the like.

Here, the plurality of heat regulating plates 32 are arranged at the boundary between two adjacent heat generating regions 341, respectively. That is, the plurality of heat regulating plates 32 are arranged so as to partition the inside of the accommodation space 66 into the plurality of heat generating spaces 661 according to the plurality of heat generating regions 341.

The plurality of connecting mechanisms 40 individually connect each of the plurality of simulated heat sources 30 to the temporary lid 20. The plurality of connecting mechanisms 40 include a first hooking portion 42 and a second hooking portion 44, respectively.

The first hooking portion 42 is provided on the lower surface of the temporary lid 20. The first hook portion 42 has a shape in which a tubular or rod-shaped member is curved in a semicircular shape, and the entire portion of the first hook portion 42 functions as a guide portion. Both ends of the first hooking portion 42 are fixed to the lower surface of the temporary lid 20. The first hooking portion 42 projects in a direction perpendicular to the lower surface of the temporary lid 20 and in a direction away from the lower surface. The center of the first hooking portion 42 is farthest from the lower surface of the temporary lid 20. The first hooking portion 42, together with the temporary lid 20, forms an annular hooking portion.

The second hooking portion 44 is provided on the upper surface of the support plate 31 included in the simulated heat source 30. The second hook portion 44 has a shape in which a tubular or rod-shaped member is curved in a semicircular shape. Both ends of the second hooking portion 44 are fixed to the upper surface of the support plate 31. The second hook portion 44 projects in a direction perpendicular to the upper surface of the support plate 31 and in a direction away from the upper surface. The center of the second hook portion 44 is farthest from the upper surface of the support plate 31. The second hook portion 44, together with the support plate 31, forms an annular hook portion. The intermediate portion of the second hook portion 44 passes between the first hook portion 42 and the temporary lid 20 (that is, the annular hook portion formed by the first hook portion 42 and the temporary lid 20). Therefore, the second hooking portion 44 can be hooked on the first hooking portion 42 in a state where the second hooking portion 44 is prevented from falling off from the first hooking portion 42.

The temperature measuring device 50 measures the surface temperature of the basket 60 in a state where at least a part thereof is housed in any one of the plurality of storage spaces 66.

The temperature measuring device 50 will be described with reference to FIGS. 5, 6 and 7. FIG. 5 is a perspective view showing a schematic configuration of the temperature measuring device 50. FIG. 6 is an enlarged drawing showing a part of FIG. 1. FIG. 7 is an enlarged drawing showing another part of FIG. 1.

The temperature measuring device 50 includes a thermocouple 51 as a contact-type temperature measuring device and a holding mechanism 52. These will be described below.

The thermocouple 51 is inserted into any of the plurality of accommodation spaces 66 and measures the surface temperature on the inner surface of the basket 60 in a state of being in contact with the inner surface of the basket 60 that partitions the accommodation space 66. The thermocouple 51 includes a terminal portion 511 that can come into contact with the inner surface of the basket 60. The terminal portion 511 allows heat transfer from the inner surface of the basket 60 in a state of being in contact with the inner surface of the basket 60. The thermocouple 51 is connected to the temporary lid 20 and can move together with the temporary lid 20.

The holding mechanism 52 is inserted into any of the plurality of accommodation spaces 66 to hold the thermocouple 51 at a position where the surface temperature on the inner surface of the basket 60 can be measured. Specifically, the holding mechanism 52 holds the terminal portion 511 of the thermocouple 51 in contact with the inner surface of the basket 60. The holding mechanism 52 is connected to the temporary lid 20 and can move together with the temporary lid 20.

The holding mechanism 52 includes an operation handle 581 as an operated portion, a frame 531 and a frame 532, a pair of pipes 54, a holding plate 55 as a pair of contact members, a pair of springs 56, and a moving mechanism 57. including. These will be described below.

The operation handle 581 is arranged so as to be operable from the outside of the container body to which the temporary lid 20 is attached. The operation handle 581 is provided on the expansion joint 58. The expansion joint 58 is arranged in the accommodating hole 22 formed in the temporary lid 20. The expansion joint 58 is a bellows type expansion joint. As a result, the sealing property of the temporary lid 20 is ensured.

The frame 531 suspends the frame 532. The frame 531 and the frame 532 are connected by a pair of pipes 54. Each of the pair of pipes 54 houses a thermocouple 51. The terminal portion 511 of the thermocouple 51 is located outside the pipe 54.

The frame 531 is connected to the temporary lid 20. Specifically, the frame 531 is connected to the temporary lid 20 by hooking the hooking portion 53A of the frame 531 on the hooking portion 24 provided on the lower surface of the temporary lid 20.

The frame 532 is arranged between the pair of presser plates 55 and supports each of the pair of presser plates 55. The frame 532 is arranged at a position away from the inner surface of the basket 60 that divides the accommodation space 66 in a state of being accommodated in any of the plurality of accommodation spaces 66. The frame 532 has a rectangular frame shape. The frame 532 surrounds the plurality of heater wires 34.

The pair of holding plates 55 are arranged in a position where they can come into contact with the inner surface of the basket 60 while being housed in the container body. The presser plate 55 supports the thermocouple 51. The terminal portion 511 of the thermocouple 51 is located in the hole 551 formed in the holding plate 55. In a state where the presser plate 55 is in contact with the inner surface of the basket 60, the terminal portion 511 is in contact with the inner surface of the basket 60 together with the presser plate 55. The presser plate 55 is movably arranged between a position in contact with the inner surface of the basket 60 (contact position) and a position away from the inner surface of the basket 60 (evacuation position).

Each of the pair of springs 56 is arranged between the presser plate 55 and the frame 532, and exerts an urging force on the presser plate 55 in the direction in which the presser plate 55 separates from the frame 532. That is, the spring 56 exerts an urging force on the presser plate 55 in the direction of moving the presser plate 55 from the retracted position toward the contact position.

The moving mechanism 57 moves each of the pair of holding plates 55 in the direction of approaching / separating from the frame 532. The presser plate 55 moves in conjunction with the operation of the operation handle 581. The direction in which the presser plate 55 moves with respect to the frame 532 corresponds to the direction in which the operation handle 581 is operated. When the presser plate 55 is brought closer to the frame 532 (that is, when the presser plate 55 is moved from the contact position to the retracted position), the operation handle 581 is operated in the first direction. When the presser plate 55 is separated from the frame 532 (that is, when the presser plate 55 is moved from the retracted position to the contact position), the operation handle 581 is operated in the second direction.

The moving mechanism 57 includes a pair of wires 571, a connecting portion 572, and a guide portion 573. These will be described below.

Each of the pair of wires 571 connects the holding plate 55 and the connecting portion 572. Each pair of wires 571 is housed in a pipe 54.

The connection portion 572 is provided in the telescopic joint 58 and moves in accordance with the operation with respect to the operation handle 581, so as to bring the presser plate 55 closer to the frame 532 against the urging force of the spring 56 (that is, the presser plate). A tensile force) that causes the 55 to move from the contact position to the retracted position) is applied to the wire 571.

The guide portion 573 guides the movement of the wire 571 accompanying the operation of the operation handle 581. In the present embodiment, the guide portion 573 is realized by the pipe 54 accommodating the wire 571. The guide portion 573 has a portion in the vicinity of the presser plate 55 that extends in the direction in which the presser plate 55 approaches / separates from the frame 532. As a result, the direction in which the tensile force of the wire 571 acts on the presser plate 55 is opposite to the direction in which the urging force of the spring 56 acts on the presser plate 55.

Subsequently, a heat transfer test using the heat transfer test device 10 will be described. In the heat transfer test, the simulated heat source 30 is inserted into each of the plurality of storage spaces 66 partitioned by the grid-like baskets 60 arranged in the container body, and the surface temperatures of the container body and the basket 60 are measured and designed. Occasionally make sure that the temperature does not exceed the temperature obtained by analysis.

When conducting a heat transfer test, prepare for the heat transfer test. Specifically, the heat transfer test device 10 is attached to the container body of the cask. The work will be described below.

First, a temporary lid 20 in which each of the plurality of simulated heat sources 30 is connected by the connecting mechanism 40 is prepared.

Subsequently, the temporary lid 20 is moved above the container body. At this time, each of the plurality of simulated heat sources 30 is suspended from the temporary lid 20 by the action of gravity. Specifically, the second hooking portion 44 provided on the support plate 31 of the simulated heat source 30 is hooked on the first hooking portion 42 provided on the lower surface of the temporary lid 20 by the action of gravity. At this time, the second hooking portion 42 is in contact with the portion of the first hooking portion 42 closest to the simulated heat source 30.

Further, when each of the plurality of simulated heat sources 30 is suspended from the temporary lid 20, the temperature measuring device 50 is also suspended from the temporary lid 20.

Subsequently, the temporary lid 20 is aligned so that each of the plurality of simulated heat sources 30 is located directly above the corresponding accommodation space 66 among the plurality of accommodation spaces 66. After that, the temporary lid 20 is lowered toward the container body. As a result, each of the plurality of simulated heat sources 30 is simultaneously inserted into the corresponding accommodation space 66.

Each of the plurality of simulated heat sources 30 descends within the corresponding accommodation space 66. Here, before the temporary lid 20 comes into contact with the container body, the lower end of each of the plurality of simulated heat sources 30 (that is, the lower surface of the support plate 33 possessed by each of the plurality of simulated heat sources 30) is the bottom surface 18 of the container body (FIG. 1). See). Therefore, only the temporary lid 20 continues to descend toward the container body. At this time, the first hooking portion 42 provided on the temporary lid 20 moves downward with respect to the second hooking portion 44 provided on the simulated heat source 30, so that the second hooking portion 44 becomes the first hooking portion. The state in which the movement of the second hooking portion 44 is restrained by the first hooking portion 42 is released from the contact with the 42. In other words, the second hooking portion 44 will not be hooked on the first hooking portion 42. As a result, the simulated heat source 30 can move in any direction within the accommodation space 66.

In this state, the temporary lid 20 is attached to the container body. When attaching the temporary lid 20 to the container body, for example, bolts are used.

With the temporary lid 20 attached to the container body, the inside of the container body is maintained in a decompressed state. Helium gas is sealed in the container body.

When the temporary lid 20 is attached to the container body as described above, the temperature measuring device 50 is inserted into any of the plurality of accommodation spaces 66 with each of the pair of holding plates 55 held in the retracted position. Therefore, the pair of pressing plates 55 are accommodated in the accommodating space 66 without coming into contact with the basket 60.

The operation handle 581 is operated in the second direction with the temporary lid 20 attached to the container body. As a result, the connecting portion 572 rotates in a predetermined direction, and the tensile force due to the wire 571 is released. That is, the force that prevents the presser plate 55 from moving in the direction away from the frame 532 due to the urging force of the spring 56 does not act on the presser plate 55. In other words, the force that prevents the presser plate 55 from moving from the retracted position to the contact position due to the urging force of the spring 56 does not act on the presser plate 55. Therefore, the pressing force of the spring 56 causes the holding plate 55 to move in the direction away from the frame 532. That is, the holding plate 55 moves from the retracted position toward the contact position. Such movement of the presser plate 55 is prevented by the presser plate 55 coming into contact with the inner surface of the basket 60 (the side surface defining the accommodation space 66). That is, the pressing plate 55 is pressed against the inner surface of the basket 60 by the urging force of the spring 56. As a result, the terminal portion 551 of the thermocouple 51 attached to the holding plate 55 comes into contact with the inner surface of the basket 60.

Before the heat transfer test, in order to confirm that the terminal portion 511 and the holding plate 55 are in contact with the inner surface of the basket 60, a through hole is provided in the temporary lid 20, and the through hole is used for industrial purposes as an image pickup device. An endoscope (for example, a fiberscope or a videoscope) may be inserted so that the terminal portion 511 and the holding plate 55 can be confirmed to be in contact with the inner surface of the basket 60. In this case, after confirming that the terminal portion 511 and the holding plate 55 are in contact with the inner surface of the basket 60, the industrial endoscope is taken out from the through hole of the temporary lid and the through hole is sealed. , The heat transfer test should not be affected.

After making such preparations, a heat transfer test is performed. In the heat transfer test, each of the plurality of simulated heat sources 30 is heated by passing a current through the heater wires 34 of each of the plurality of simulated heat sources 30. As a result, the calorific value and the exothermic region of the spent fuel are simulated.

In this state, the surface temperature of the basket 60 and the surface temperature of the container body are measured, and it is confirmed that the temperature does not exceed the temperature obtained by the analysis at the time of design.

The heat transfer test is performed in a state where the container body is vertically placed (that is, a state in which the accommodation space 66 extends in the vertical direction) and a state in which the container body is placed horizontally (that is, a state in which the storage space 66 extends in the horizontal direction). .. Here, when the container body is placed vertically, each of the plurality of simulated heat sources 30 is in contact with the bottom surface 18 of the container body. On the other hand, when the container body is placed horizontally, each of the plurality of simulated heat sources 30 is in contact with the inner surface of the basket 60. This is because each of the plurality of simulated heat sources 30 is not constrained in movement within the accommodation space 66. By doing so, it is possible to simulate the movement of the spent fuel in the accommodation space 66.

When such a heat transfer test is completed, the heat transfer test device 10 is removed from the container body. The work will be described below.

First, the operation handle 581 is operated in the first direction. As a result, the connecting portion 572 rotates in a direction opposite to the predetermined direction. As a result, a tensile force is applied to the wire 571. When this tensile force acts on the presser plate 55, the presser plate 55 moves in the direction approaching the frame 532 against the urging force of the spring 56. That is, the holding plate 55 moves from the contact position toward the retracted position against the urging force of the spring 56. Therefore, the holding plate 55 is separated from the inner surface of the basket 60. That is, the terminal portion 511 of the thermocouple 51 is separated from the inner surface of the basket 60.

After making such a state, the state in which the temporary lid 20 is attached to the container main body is released, and the temporary lid 20 is lifted upward from the container main body. At the initial stage, since the second hooking portion 44 is not hooked on the first hooking portion 42, only the temporary lid 20 moves upward, but the second hooking portion 44 moves to the first hooking portion 42 from the middle. Since they are caught, each of the plurality of simulated heat sources 30 is suspended from the temporary lid 20, and as the temporary lid 20 moves upward, each of the plurality of simulated heat sources 30 also moves upward. As a result, each of the plurality of simulated heat sources 30 is withdrawn from the corresponding accommodation space 66. In this way, the heat transfer test device 10 is removed from the container body.

In the heat transfer test apparatus 10, the thermocouple 51 can be inserted into the container body in which the basket 60 is housed by lowering the temporary lid 20 from above the container body toward the container body. Further, after the thermocouple 51 is inserted into the container body in which the basket 60 is housed, the thermocouple 51 can be held at a position where the surface temperature on the inner surface of the basket 60 can be measured. Therefore, it is not necessary to fix the thermocouple while assembling the basket 60, or to insert the basket 60 to which the thermocouple is fixed into the container body. As a result, the work of holding the thermocouple 51 at a position where the surface temperature on the inner surface of the basket 60 can be measured can be efficiently performed. Therefore, in the heat transfer test apparatus 10, the time required for preparing the heat transfer test can be shortened, and the heat transfer test can be efficiently performed.

In the heat transfer test apparatus 10, when the temporary lid 20 is lowered toward the container body, the presser plate 55 to which the terminal portion 511 of the thermocouple 51 is attached is prevented from coming into contact with the basket 60. Even when the thermocouple 51 is adopted as the temperature measuring device, the thermocouple 51 can be moved to a position where the surface temperature can be measured without contacting the container body and the basket 60.

In the heat transfer test apparatus 10, when the terminal portion 511 of the thermocouple 51 is brought into contact with the inner surface of the basket 60, not only the terminal portion 511 but also the holding plate 55 to which the terminal portion 511 is attached is placed on the inner surface of the basket 60. Since they are brought into contact with each other, the contact state of the terminal portion 511 with respect to the inner surface of the basket 60 can be stabilized.

In the heat transfer test apparatus 10, the pressing plate 55 to which the terminal portion 511 of the thermocouple 51 is attached is brought into contact with the inner surface of the basket 60 by using the urging force of the spring 56, so that the terminal portion 511 with respect to the inner surface of the basket 60 is brought into contact with the inner surface of the basket 60. The contact state of can be stabilized.

In the heat transfer test apparatus 10, a mechanism driven by an electric signal is used, for example, because the contact state and the non-contact state of the presser plate 55 with respect to the inner surface of the basket 60 are switched by the mechanical operation using the wire 571. Compared with the case, it is possible to improve the reliability of the operation of bringing the terminal portion 511 attached to the presser plate 55 into contact with the inner surface of the basket 60.

In the heat transfer test apparatus 10, the presser plate 55 can be brought into contact with the inner surface of the basket 60 so as to be stretched on both sides of the frame 532. As a result, the contact state of the holding plate 55 with respect to the inner surface of the basket 60 can be further stabilized.

In the heat transfer test apparatus 10, since the wire 571 and the thermocouple 51 are housed in the pipe 54, the wire 571 and the thermocouple 51 can be protected by the pipe 54.

[Modified example of the embodiment]
A modified example of the holding mechanism will be described with reference to FIGS. 8, 9 and 10. FIG. 8 is a side view showing the holding mechanism 70. FIG. 9 is a plan view showing a state in which the thermocouple 51 is not in contact with the inner surface of the basket 60 by the holding mechanism 70. FIG. 10 is a plan view showing a state in which the thermocouple 51 is in contact with the inner surface of the basket 60 by the holding mechanism 70.

The holding mechanism 70 includes a pair of contact members 72, a link mechanism 74, a spring 76, and a wire 78. These will be described below.

The pair of contact members 72 are arranged in a position where they can come into contact with the inner surface of the basket 60 while being housed in the container body. The pair of contact members 72 are located on both sides of the heater wire 34. The contact member 72 moves between a position in contact with the inner surface of the basket 60 (contact position) and a position away from the inner surface of the basket 60 (evacuation position). Each of the pair of contact members 72 is connected to the heat regulating plate 32 by a hanging wire 80. The contact member 72 supports the thermocouple 51. The terminal portion 511 of the thermocouple 51 is arranged so as to project outward from the side surface of the contact member 72 by the urging force of the spring 73.

The link mechanism 74 connects a pair of contact members 72. With the operation of the link mechanism 74, the distance between the pair of contact members 72 changes.

The spring 76 exerts an urging force on the link mechanism 74 so that the link mechanism 74 has a form that widens the distance between the pair of contact members 72.

The wire 78 connects the link mechanism 74 and the connecting portion 572. The tensile force of the wire 78 acts on the link mechanism 74, so that the link mechanism 74 changes its form against the urging force of the spring 76.

In such a holding mechanism 70, by pulling the wire 78, as shown in FIGS. 8 and 9, the link mechanism 74 puts each of the pair of contact members 72 into the basket 60 against the urging force of the spring 76. Deforms to move away from the inner surface of the, and maintains that state. Therefore, each of the pair of contact members 72 is held in the retracted position. At this time, the terminal portion 511 of the thermocouple 51 projects outward from the side surface of the contact member 72 due to the urging force of the spring 73, but is located at a position away from the inner surface of the basket 60. In this state, the holding mechanism 70 is inserted into the accommodation space 66 and moves in the accommodation space 66. Therefore, the holding mechanism 70 can be moved to a position where the temperature can be measured by the thermocouple 51 while avoiding the holding mechanism 70 from coming into contact with the basket 60.

Further, by releasing the tensile force exerted on the wire 78, as shown in FIG. 10, the link mechanism 74 brings each of the pair of contact members 72 into contact with the inner surface of the basket 60 by the urging force of the spring 76. It transforms like this. Each of the pair of contact members 72 moves to the contact position by the urging force of the spring 76 and is pressed against the inner surface of the basket 60. In this state, the terminal portion 511 of the thermocouple 51 is pressed against the inner surface of the basket 60 by the urging force of the spring 73. That is, the thermocouple 51 is held at a position on the inner surface of the basket 60 where the surface temperature is measured. In this state, the surface temperature on the inner surface of the basket 60 is measured by the thermocouple 511.

Even when such a holding mechanism 70 is provided, the thermocouple 51 can be held at a position where the surface temperature on the inner surface of the basket 60 can be measured, as in the above embodiment, so that the heat transfer test can be performed. Preparation can be done efficiently.

Further, in the holding mechanism 70, since the terminal portion 511 of the thermocouple 51 can be brought into contact with the inner surface of the basket 60 by using the urging force of the spring 73, the terminal portion 511 of the thermocouple 51 can be brought into contact with the inner surface of the basket 60. It is possible to stabilize the state of being in contact with the water.

Although the embodiments of the present invention have been described in detail above, these are merely examples, and the present invention is not to be interpreted in a limited manner by the description of the above-described embodiments.

For example, in the above embodiment, a contact type temperature measuring device is adopted, but the temperature measuring device may be a non-contact type. When a non-contact temperature measuring device is adopted, there may be no contact member or a mechanism for moving the contact member.

For example, in the above embodiment, the presser plate 55 has been described as an example of the contact member, but the contact member is not particularly limited as long as it has a region in contact with the inner surface of the basket around the terminal portion. The contact member may be in point contact or line contact with the inner surface of the basket.

For example, in the above embodiment, the case of measuring the surface temperature on the inner surface of the basket 60 has been described, but the surface temperature on the inner surface of the container body is measured in the same manner as the case of measuring the surface temperature on the inner surface of the basket 60. May be good.

For example, the driving force for moving the holding plate against the urging force of the spring may be an electromagnetic force. Such a driving force can be obtained by using, for example, a solenoid.

For example, in the above embodiment, the guide portion 573 that guides the movement of the wire 571 is realized by the pipe 54, but the movement of the wire may be guided by using a pulley or the like.

For example, in the above embodiment, the terminal portion 511 of the thermocouple 51 is located in the hole 551 formed in the presser plate 55 that supports the thermocouple 51, and the presser plate 55 comes into contact with the inner surface of the basket 60. In this state, the terminal portion 511 was in contact with the inner surface of the basket 60 together with the presser plate 55, but the contact plate in which the terminal portion 511 of the thermocouple 51 was embedded was adopted instead of the presser plate 55, and the terminal portion of the thermocouple 51 was adopted. Heat conduction from the inner surface of the basket 60 may be allowed through the contact plate in which the 511 is in contact with the inner surface of the basket 60.

10 Heat transfer test device 20 Temporary lid 51 Thermocouple 511 Terminal part 52 Holding mechanism 531 Frame 53A Frame 532 Frame 54 Pipe 55 Pressing plate 56 Spring 57 Moving mechanism 571 Wire 571 Connection part 573 Guide part

Claims (8)

Used for transporting and / or storing the spent fuel in a state where the spent fuel is contained in each of a plurality of storage spaces defined by a grid-shaped basket and extending in a predetermined direction in a parallel state to each other. Confirm the heat transfer function of the container including the container body in which the opening for inserting the basket from the outside is formed and the container body for accommodating the basket and the container lid attached to the container body so as to cover the opening of the container body. It is a heat transfer test device used for heat transfer test for
A temporary lid that can be attached to the container body instead of the container lid,
A temperature measuring device capable of measuring the surface temperature on the inner surface of the container body or the inner surface of the basket.
When the temporary lid is lowered toward the container body from above the container body in a state where each of the plurality of accommodation spaces is open upward, the temperature measuring device is supported and the temporary lid is combined with the temporary lid. A heat transfer test including a holding mechanism that is connected to the temporary lid so as to be inserted into the container body together with the temperature measuring device by moving and holds the temperature measuring device at a position where the surface temperature can be measured. Device. The heat transfer test apparatus according to claim 1.
The temperature measuring instrument is
Includes a terminal portion to allow thermal conduction from the inner surface of the basket in a state in which the direct or indirect contact with the inner surface of a direct or indirect contactable said basket inner surface of the basket, the terminal A contact-type temperature measuring device that measures the surface temperature on the inner surface of the basket in a state where the portion is in direct or indirect contact with the inner surface of the basket.
The holding mechanism is
Including the operated portion that can be operated from the outside of the container body with the temporary lid attached.
The terminal portion is held so that the terminal portion can move between the retracted position away from the inner surface of the basket and the contact position in direct or indirect contact with the inner surface of the basket in the container body. death,
A heat transfer test device that moves the terminal portion between the retracted position and the contact position in conjunction with an operation on the operated portion. The heat transfer test apparatus according to claim 2.
The holding mechanism is
A heat transfer test apparatus including a contact member that is movably arranged together with the terminal portion while supporting the terminal portion and that contacts the inner surface of the basket together with the terminal portion in a state where the terminal portion is located at the contact position. The heat transfer test apparatus according to claim 2.
The holding mechanism is
A contact member that is movably arranged together with the terminal portion while supporting the terminal portion and can be contacted with the inner surface of the basket is included.
A heat transfer test in which the terminal portion indirectly contacts the inner surface of the basket through the contact member in contact with the inner surface of the basket to measure the surface temperature on the inner surface of the basket. Device. The heat transfer test apparatus according to claim 3 or 4.
The holding mechanism further
A frame suspended from the temporary lid and supporting the contact member,
A spring, which is arranged between the contact member and the frame and gives an elastic force, which is an urging force in a direction in which the terminal portion moves from the retracted position toward the contact position, to the contact member.
In conjunction with the first operation on the operated portion, the terminal portion is moved from the contact position toward the retracted position against the urging force, and in conjunction with the second operation on the operated portion. A heat transfer test apparatus including a moving mechanism for moving the terminal portion from the retracted position to the contact position by the urging force. The heat transfer test apparatus according to claim 5.
The moving mechanism is
A wire whose one end is connected to the contact member,
The other end of the wire is connected and moves in accordance with the first operation with respect to the operated portion so that the terminal portion is moved from the contact position to the retracted position against the urging force. By applying a sufficient tensile force to the wire and moving it with respect to the operated portion in accordance with the second operation, the tensile force is released, and the terminal portion is moved from the retracted position to the contact position by the urging force. The connection part to move toward,
A heat transfer test device including a guide portion that guides the wire so that the direction in which the urging force acts on the contact member coincides with the direction in which the terminal portion moves from the retracted position toward the contact position. .. The heat transfer test apparatus according to claim 5 or 6.
A heat transfer test apparatus in which the contact members are arranged on both sides of the frame in a direction perpendicular to the direction in which the temporary lid is lowered from above the container body toward the container body. The heat transfer test apparatus according to any one of claims 3 to 7.
A heat transfer test device further comprising an image pickup device that is inserted into the container body through a through hole formed in the temporary lid and can photograph a state in which the contact member is in contact with the inner surface of the basket.

Images