JPH07325191A - Transportation stage for wet transportation cask - Google Patents

Abstract

PURPOSE:To provide a transportation stage capable of surely fixing and supporting a wet transportation cask containing spent nuclear fuel and water together on the loading part of a transportation vehicle, promoting the cooling function of the supported wet transportation cask, and suppressing the escalation of internal temperature and pressure. CONSTITUTION:A transportation stage is constituted by standing support parts 2 provided on both sides of a pair of support column parts 2a having cramps 3 at the top ends on both ends in front and back of a flat base 1 put and connected to the loading part of a vehicle and arranging an elevation cylinder 4 at the bottom end of the pair of support columns 2a of those support part 2. Therefore, the inclination of the supported wet transportation cask can be changed during transportation by elevating one of front or back supports in turn to promote the flow of the contained water in the axis direction and promote the cooling function by raising heat transfer performance inside the wet transportation cask.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle for transporting a wet transportation container containing spent nuclear fuel generated from a nuclear power plant or the like to a predetermined storage place or facility. It relates to a transportation platform that is secured and supported on.

[0002]

2. Description of the Related Art Spent nuclear fuel generated from a nuclear power plant or the like generates a large amount of decay heat from itself due to self-destruction or spontaneous fission of radionuclides. Various measures have been taken, such as putting water inside the transportation container itself and providing fins for heat dissipation on the outer peripheral surface.

The outer shape of a typical wet transport container among them is shown in FIG. 2 (d). This wet shipping container
(C)) is formed in a cylindrical sealed pressure vessel, and a large number of heat radiating fins (F) are provided on the outer peripheral surface of the body portion, and 2
It has a pair of trunnions (T). Then, in the wet transport container (C), an assembly of spent nuclear fuel pins and a basket for holding the assembly are housed, and the basket is filled with water.

Further, conventionally, this type of wet transportation container (C) has been used.
As shown in Figures (a) and (b) of the front and side views, the transportation platform required for transporting the ) And a support part (12) which is erected on both front and rear ends of this base (11) and has a pair of left and right clamps (13) provided on the upper end of the base (11). Has been adopted as Then, the wet transport container (C) holds the trunnions (T) at both ends with the pair of clamps (13) of the front and rear support parts (12) of the transport base, as shown in FIG. Then, it is horizontally secured and supported via the transportation base to a mounting portion of a transportation vehicle (not shown here).

[0005]

However, in the above-described conventional transportation stand, since the wet transportation container is supported horizontally, the space between the assembly of the spent fuel pins housed in the wet transportation container and the basket. Since the water in the column does not flow efficiently in the axial direction of the wet transport container, the decay heat is transferred only by the radial convective heat transfer, and as a result, the internal temperature of the supported wet transport container is high. Then, there was a problem that the internal pressure was increased accordingly. That is, the above-mentioned conventional transportation cradle has the main purpose of securely securing and supporting the wet transportation container to prevent an accident such as a drop during transportation. It was not specifically designed.

The present invention addresses the above-mentioned problems of the prior art. It supports a wet transportation container containing water together with spent nuclear fuel, and can be securely fastened to a mounting portion of a transportation vehicle. , To the supported wet transport container, the water contained therein can be moved to promote axial flow according to the amount of decay heat of the spent nuclear fuel, thereby promoting its heat removal function. An object of the present invention is to provide a transportation platform for a wet transportation container, which can suppress an increase in internal temperature and internal pressure of the wet transportation container during transportation.

[0007]

In order to achieve the above object, the present invention has the following constitution. That is, the transportation platform of the wet transport container according to the present invention includes a flat plate-shaped base mounted and connected to a mounting portion of a vehicle, and is erected on both front and rear ends of the base, and the left and right sides are installed at the upper end of the base. And a pair of front and rear supports provided with clamps, and two pairs of trunnions provided at both ends of a wet transportation container containing spent nuclear fuel together with water are held by the clamps of the supports. In a transportation platform for a wet transportation container that transports a wet transportation container by fixing it to a vehicle mounting portion, at least one of the front and rear supporting portions is provided with the supporting portion itself or a pair of upper end clamps. It is characterized in that a cylinder device for raising and lowering is provided.

[0008]

In the transportation base according to the present invention, front and rear supporting portions having a pair of left and right clamps at the upper end thereof are erected on both front and rear ends of the base mounted and connected to the vehicle mounting portion. Because
The two pairs of trunnions provided at both ends of the wet transportation container can be gripped by the respective clamps of the front and rear supporting portions, and the wet transportation container can be securely bound and supported on the vehicle mounting portion for transportation. . In addition, since at least one of the front and rear supporting parts is provided with a cylinder device for raising and lowering the supporting part itself or a pair of upper end clamps, the cylinder device is operated and supported during transportation. By changing the inclination of the wet transport container, the water contained in the wet transport container is urged to flow in the axial direction in accordance with the decay heat amount of the spent nuclear fuel stored together,
It is possible to enhance the internal heat transfer performance, thereby promoting the heat removal function of the wet transportation container, and suppressing an increase in internal temperature and internal pressure during transportation.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. [FIG. 1] is a drawing showing a schematic configuration of one embodiment of a transportation platform according to the present invention, in which (a) is a front view with a part cut away, (b) is a side view, (C) ) The figure is an illustration of the support and operating state of the wet transport container.

In (a) and (b) of FIG. 1,
(1) is a base, and the base (1) is formed in a rectangular flat plate shape, and a lifting hook engaging portion and a connecting fixture to a vehicle mounting portion (not shown) are attached here. Be prepared.

(2) is a support part, and the support part (2)
Are erected on both front and rear ends of the base (1), and a pair of support columns (2a) are provided on both left and right sides of the base (1).
The lower part of a) is connected by a plate-shaped cross girder (2b) to be integrated. In addition, each pair of support columns (2a) is provided with a pair of clamps (3) at the upper end to hold the shaft body freely on the left and right, while raising and lowering in synchronization with the supply of hydraulic pressure from the outside. The cylinder (4) is installed at the lower end, and the lower end of the ram (4a) of the lifting cylinder (4) is connected to the upper surface of the base (1). (1) Standing on top. In addition, each clamp of the support part (2) before and after it
A bearing (3a) for smoothing the rotation of the shaft-like body to be gripped is arranged in the lower part of the load-carrying part of (3).

In the transportation platform of this embodiment having the above-mentioned structure, when the wet transportation container containing the spent nuclear fuel and water is transported to a predetermined storage place or facility, the trunnions on both ends of the wet transportation container are moved forward and backward. It is gripped by a pair of clamps (3) on the left and right sides of the support part (2), and is secured and supported by a mounting part of a transportation vehicle (not shown here). The target wet transport container is the same type as the wet transport container (C) shown in (d) of FIG. 2, and a large number of heat radiation fins (F) are provided on the outer peripheral surface of the body, It is a cylindrical sealed pressure vessel having two pairs of trunnions (T) at both ends, and an assembly of spent nuclear fuel pins and a basket holding the assembly are housed inside the container. The basket is filled with water. And two pairs of trunnions (T) at both ends are
As shown in (c) of FIG. 1, the clamps (3) of the front and rear supporting portions (2) of the transportation base of this embodiment are freely rotatably gripped, so that they can be mounted on the transportation vehicle. Secured and supported.

Here, in the transportation platform according to the present embodiment, the lifting cylinder (4) having the supporting portions (2) at the front and rear thereof arranged at the lower end portion.
Since it can be lifted up and down by means of one of the supporting parts (2) in front of and behind it, as shown in FIG.
The slope of (C) can be changed at any time.

Therefore, in the transportation platform of this embodiment, the inclination of the wet transportation container (C) supported by actuating the lifting cylinder (4) is changed during transportation, and the wet transportation container (C) is changed.
The water contained in the inside of the wet transport container (C) enhances the heat transfer performance of the inside by accelerating the flow of water in the axial direction according to the decay heat amount of the spent nuclear fuel contained together. The heat removal function of can be promoted. Furthermore, the inclination angle of the wet transport container (C) to be supported corresponds to the amount of decay heat of the spent nuclear fuel contained and is set to the optimum angle for calculation, so that the radial direction can be increased as in the prior art. Compared with the heat transfer performance in a wet transport container that depends only on the convective heat transfer of
Since it is expected that the heat transfer efficiency will be doubled, it is possible to suppress the increase in the internal temperature and internal pressure of the supported wet transport container (C), and also to transport the spent nuclear fuel that generates higher decay heat than before.

In the transportation platform of this embodiment, the front and rear supporting portions (2) are provided with lifting cylinders (4) at the lower end portions of the pair of supporting columns (2a), and both of them are individually or alternately arranged. Although it was configured to be able to move up and down, one of the front and rear support parts (2)
A supported wet transport container, even if it is fixedly installed on the base (1) and only the other support part (2) is moved up and down.
The same effect as above can be obtained by changing the inclination of (C). In addition, the pair of strut parts (2a) on the left and right of each of the front and rear support parts (2) are connected by a cross beam (2b) to be integrated, but the pair of strut parts (2a) on the left and right are As long as the lifting cylinders (4) provided at the respective lower ends can be moved up and down in synchronism with each other, the horizontal beams (2b) may be omitted to stand independently. In addition, the lifting cylinder (4) is arranged at the lower end of each column (2a) to raise and lower the support part (2) itself.
The lift cylinder (4) is interposed between the upper part of each column (2a) and each clamp (3), so that the front and rear supports (2) are fixed on the base (1). On the other hand, while being installed, the clamps (3) at the upper end may be moved up and down. Also,
The lifting cylinder (4) is a hydraulic type that operates by receiving hydraulic pressure from the outside, but this is an example.
To counter the component force of the weight of the wet transport container (C) that is loaded,
It goes without saying that, as long as the front and rear support portions (2) or the respective clamps (3) are moved up and down and stopped and held at the set height positions, for example, an electric type may be used.

[0016]

As described above, according to the transportation stand of the present invention, the wet transportation container containing water together with the spent nuclear fuel is supported and can be securely fastened to the mounting portion of the transportation vehicle. During transportation, the inclination of the supported wet transport container was changed, and the water contained in the wet transport container moved in the axial direction according to the decay heat amount of the spent nuclear fuel contained together. To increase the internal heat transfer performance, thereby promoting the heat removal function of the wet transport container, thereby suppressing the increase in the internal temperature and internal pressure of the wet transport container during transportation, Spent nuclear fuel that produces decay heat can also be transported.

[Brief description of drawings]

1A and 1B are drawings showing a schematic configuration of one embodiment of a transportation platform according to the present invention, in which FIG. 1A is a front view with a part cut away, FIG. 1B is a side view, and FIG. FIG. 6 is an explanatory view of the support and operating state of the wet transport container.

2A and 2B are explanatory views of a conventional transportation base, where FIG. 2A is a front view, FIG. 2B is a side view, and FIG. 2C is an explanatory view of a supporting state of a wet transportation container; FIG. 3 is an explanatory view of an outer shape of a typical wet transportation container.

[Explanation of symbols] (1) --Base (2) --Support (3) --Clamp (4) --Lift cylinder (C) --Wet transport container (T) --Trunion

Claims (1)

[Claims] 1. A flat plate-shaped base that is placed and connected to a mounting portion of a vehicle, and a front and a rear stand that are erected on both front and rear ends of the base and have a pair of left and right clamps provided at their upper ends. A pair of trunnions provided at both ends of a wet transportation container having a support portion and containing spent nuclear fuel together with water are held by respective clamps of the support portion, and the wet transportation container is mounted on a vehicle mounting portion. In a transportation platform for a wet transportation container to be bound and transported, at least one of the front and rear supporting portions is provided with a cylinder device for raising and lowering the supporting portion itself or a pair of upper end clamps. A transportation platform for a wet transportation container.