JP2954151B1 - Cask basket - Google Patents

Abstract

An object of the present invention is to provide a high-precision and excellent heat transfer performance, and to manufacture it at low cost. A plurality of fuel insertion holes (7) and an insertion slit (9) for inserting a plurality of bron-added aluminum alloy plates (8) are formed at predetermined positions of an aluminum alloy plate-like block (3) having a certain thickness by machining. And a plurality of rod insertion holes 10 are respectively formed through through in the thickness direction, and the plurality of plate-like blocks 3 are overlapped in the thickness direction, and the rod insertion holes 10 are formed.
The tie rods 5 inserted into each other tightened them together.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to relates to a cask basket to be used for storage and transport and store the spent fuel used in nuclear power plants and the like.

[0002]

2. Description of the Related Art Conventionally, in a dry cask, an aluminum alloy has been used as a material of a basket in order to improve heat removal performance. In a cask basket for storing spent fuel, for example, a fuel insertion hole is formed by aligning and welding the openings of an aluminum alloy channel material, and a neutron absorbing material is interposed between the plurality of joining channel materials and assembled. In some cases, a basket is formed by assembling a plate made of an aluminum alloy containing a neutron absorber.

[0003]

However, in the case of using a channel material, it is difficult to manufacture a basket with high dimensional accuracy due to dimensional tolerance of the channel material itself and distortion and deformation at the time of welding. Was. Further, in the case of using an aluminum alloy plate, there is a problem that a large amount of time and advanced processing techniques are required to increase the dimensional tolerance of the plate and the processing and assembling accuracy, thereby increasing the cost.

[0004] The present invention is to solve the above problems, provides excellent heat transfer performance with high accuracy, and to provide a cask <br/> basket that can be manufactured at low cost.

[0005]

In order to achieve the above-mentioned object, a cask basket according to the present invention is provided with one basket in a height direction.
Multiple plates made of aluminum alloy divided by fixed thickness
Blocks and the lower end faces of these laminated plate blocks
Located on the lower end block and upper end face
Upper plate block, each plate block and upper and lower
A plurality of end plates communicate with each other in the height direction at predetermined positions.
A fuel insertion hole and a plurality of rod insertion holes are formed.
Between multiple fuel insertion holes in the block and top plate block
In addition, there are multiple insertion slits for inserting a boron-added aluminum alloy plate.
Several inserts are formed on the lower end plate block.
A drain hole is formed corresponding to the lit, and each plate-shaped block
And positioning pins projecting from the upper surface of the bottom plate
And the pin on which the positioning pin is fitted on the lower surface
A hole is formed, and the upper and lower end plates are inserted into the rod insertion hole.
Tyro that tightens and integrates plate-like blocks between blocks
This is provided with a pad.

[0006]

According to the above construction, a plurality of aluminum alloy plate-like blocks are stacked between the upper and lower end plate blocks to lock them.
Because signed by the inserted tie rod to de insertion hole to integrate, Ru can be performed in a short time easy to assemble. Further, since the fuel insertion hole, the insertion slit, and the rod insertion hole are formed in the plate-like block by machining, it can be formed with high precision, and the whole can be made uniform to improve the heat transfer performance. In addition, the upper and lower plate blocks
Assembled with positioning pins formed on plate and block
In addition to increasing accuracy, these positioning pins
Support external force applied in the shear direction and the shear force
To prevent misalignment between each block.
You.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a cask basket according to the present invention will be described with reference to FIGS.

As shown in FIGS. 1 and 2, the basket 1 comprises a plate-like block 3 stacked in plural layers between upper and lower end plate blocks 2 and 4, an end plate block 2, 4 and a plate-like block. 4 tie rods 5 for connecting and fixing 3
The material other than the tie rod 5 is an aluminum alloy, for example, A.I. A symbol 5083.

The end plate blocks 2 and 4 and the plate-like block 3
As shown in FIGS. 3 and 4, a block body 6, 6 'formed into a cylindrical shape by forging or the like is formed by machining (cutting). Each plate-like block 3 is formed in the same shape. In each block main body 6, for example, 61 fuel insertion holes 7 having a square cross section are formed at a predetermined pitch, for example, through 61 in the thickness direction, and shown in FIG. Partition and block body 6 that partition fuel insertion hole 7
Further, an insertion slit 9 for inserting a neutron absorbing material, for example, a boron-added aluminum alloy plate 8 is formed. Further, a rod insertion hole 10 into which the tie rod 5 is inserted is formed through the thickness direction in the outer peripheral portion of the block body 6 at four positions on the outer periphery.
Further, a plurality of guide grooves 11 for inserting into and removing from the cask are formed on the outer peripheral portion of the block main body 6 in the front-rear direction in the thickness direction. Further, a pair of positioning pins 13 project from the upper surface of the block body 6 at a predetermined angle, and pin holes 12 are formed on the lower surface of the block main body 6 so that the positioning pins 13 are fitted. Here, the positioning pins 13 are used to position the block body 6 during assembly, and
In order to prevent the displacement of the block body 6 by supporting the shear force when an external force is applied to the basket 1 in the transverse direction, a total of eight blocks are provided in four places in the figure.

The same block fuel insertion holes 7, rod insertion holes 10, guide grooves 11, positioning pins 12, and pin holes 13 as the plate-like block 3 are formed in the block main bodies 6 'of the end plate blocks 2, 4. Drain holes 14 are formed at positions corresponding to the insertion slits 9 instead of the insertion slits 9. Reference numerals 15 and 16 denote a head 5a and a tightening nut 5 of a tie rod 5 formed on the bottom and top surfaces of the end plate blocks 2 and 4 corresponding to the rod insertion hole 10, respectively.
b is a storage recess.

A method of manufacturing the basket having the above configuration will be described. First, a fuel insertion hole 7, an insertion slit 9, a rod insertion hole 10, and a pin hole 13 are respectively formed in a material block main body 6 formed by forging or the like by machining, and a positioning pin 12 is attached to manufacture the plate-shaped block 3. I do. Similarly, the end plate block 2 and the partition block 4 are manufactured.

When the lower plate block 3a is superimposed on the lower plate block 2 and the plate blocks 3 are sequentially stacked, and a predetermined number of the blocks are stacked, a boron-added aluminum alloy 8 is inserted into each insertion slit 9 respectively. Next, when the upper end plate block 4 is overlaid, the tie rod 5 is inserted into the rod insertion hole 10,
Attach the tightening nuts 5b and tighten them.
And the end plate blocks 2 and 4 are integrated.

According to the above embodiment, the plate-like block 3 is formed by machining a forged aluminum alloy material.
And the end plate blocks 2 and 4 are formed, laminated, fastened with the tie rods 5 and integrated, so that the entire basket 1 can be manufactured with extremely high accuracy without material tolerance, thermal distortion and deformation. In addition, it can be assembled in a short time without special processing, and can be manufactured at low cost.
Further, since there is no welded portion and is constituted by the integrated plate-like block 3, the whole can be made uniform and the heat transfer performance can be improved.

[0015]

According to the present invention, as described above,
Since by stacking a plurality of aluminum alloy plate blocks between the lower end plate blocks signed by the inserted tie rod to the rod insertion hole to integrate, Ru can be performed in a short time easy to assemble. Further, since the fuel insertion hole, the insertion slit, and the rod insertion hole are formed in the plate-like block by machining, it can be formed with high precision, and the whole can be made uniform to improve the heat transfer performance. further
Positions formed on upper and lower end plate blocks and plate-like blocks
The positioning pin improves the assembly accuracy and
External force applied in the transverse direction by the pin
It can support the shearing force and reduce the displacement between each block.
Can be prevented.

[Brief description of the drawings]

FIG. 1 is an overall vertical sectional view showing an embodiment of a cask basket according to the present invention.

FIG. 2 is an overall plan view of the basket.

FIG. 3 is a perspective view showing a plate-like block of the basket.

FIG. 4 is a partially enlarged plan view showing a plate-like block of the basket.

FIG. 5 is a partially enlarged plan view showing a partition plate of the basket.

FIG. 6 is an enlarged view of a portion B shown in FIG.

[Explanation of symbols]

 Reference Signs List 1 basket 2 end plate block 3 plate block 4 partition plate 5 tie rod 6, 6 'block body 7 fuel insertion hole 8 boron-added aluminum alloy plate 9 insertion slit 10 rod insertion hole 12 positioning pin 13 pin hole 14 drain hole

Continued on the front page (58) Fields surveyed (Int.Cl. ⁶ , DB name) G21F 5/008 G21C 19/32 G21F 5/012

Claims (1)

(57) [Claims] 1. An aluminum plate which is divided by a certain thickness in a height direction.
Several plate-shaped blocks made of minium alloy and
Board block arranged on the lower end face of a flat plate block
And comprising an upper end plate blocks arranged on the upper end surface, the respective plate block and the upper and lower end plate block, at a predetermined position
Multiple fuel insertion holes and multiple rod insertions communicating in the height direction
A plurality of fuel holes are formed in each plate-shaped block and upper plate block.
Insert slit for inserting boron-added aluminum alloy plate between holes
Are formed, and the insertion
Drain holes are formed corresponding to the entrance slits, and are positioned on the upper surface of each plate block and lower plate block.
A pin is projected and the positioning pin is
A pin hole to be fitted is formed, and the pin hole is inserted into the rod insertion hole and the plate is inserted between the upper and lower end plate blocks.
A cascade basket provided with a tie rod for tightening and integrating the block .