JP2008292251A - Basket structure and spent fuel cask - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive basket structure having high performance, which reduces greatly a necessary amount of materials, while fulfilling a function for keeping a lattice assembling shape and a function for transferring heat to a cask, and also to provide a spent fuel cask. <P>SOLUTION: This basket structure 50 of a spent fuel cask which is arranged in a spent fuel cask body 60, constitutes a plurality of fuel storage chambers R for storing the spent fuel. The basket structure 50 is equipped with: a fuel storage lattice 1; a support member 10 comprising corrosion-resistant steel, for supporting the fuel storage lattice 1; and a heat transfer block 30 abutting on the fringe of the fuel storage lattice 1, made of an aluminum alloy, for transferring decay heat generated from the spent fuel to the spent fuel cask body. The fuel storage lattice 1 is constituted by superposing frame plates 4, 6 made of a boron-added aluminum alloy, and structures 3, 5 between the frame plates made of stainless steel. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a basket structure that functions to maintain the shape of a fuel storage lattice and to transmit heat to a spent fuel cask body, and a spent fuel cask that includes the basket structure.

  As shown in FIG. 8, the spent fuel cask has a spent fuel cask main body 60 and a basket structure that is arranged in the spent fuel cask main body 60 and constitutes a plurality of fuel storage chambers for storing spent fuel. 50. Such a spent fuel cask ensures the structural soundness and sealing of the internal atmosphere throughout the entire period of use according to its application, and the basket structure 50 ensures the subcriticality when loading spent fuel. Therefore, it is necessary to ensure heat transfer so as not to cause damage due to overheating of the fuel due to decay heat.

Such a spent fuel cask basket structure is a spent fuel container basket structure in which a plurality of storage chambers are disposed inside the spent fuel container to store spent fuel. A plurality of rectangular tube materials for forming a storage chamber into which spent fuel can be inserted, and a plurality of rectangular tube materials arranged in a stacked manner, and covering the outer periphery of these rectangular tube assemblies and fixing the rectangular tube material It was composed of a support member, an upper plate attached to the upper surface of the rectangular tube material assembly and formed with an insertion port communicating with the rectangular tube material, and a bottom plate attached to the lower surface of the rectangular tube assembly. There is a basket structure for spent fuel containers characterized by the above (for example, see Patent Document 1).
Japanese Patent Laid-Open No. 9-159796

  However, since there is a weight restriction when applied to an actual machine, most members of the basket structure disclosed in Patent Document 1 are made of a light alloy such as an aluminum alloy containing boron-added aluminum (hereinafter B-Al). It is necessary, and material cost increases and it becomes high cost.

  The present invention has been made in consideration of such points, and the required amount of material can be greatly reduced while performing the function of maintaining the shape of the lattice assembly and the function of transferring heat to the cask. Another object of the present invention is to provide a basket structure having high performance at a low cost, and a spent fuel cask having the basket structure.

The present invention is a basket structure that is arranged in a spent fuel cask body and constitutes a plurality of fuel storage chambers for storing spent fuel.
A fuel storage grid configured by superimposing a frame plate made of boron-added aluminum alloy and an inter-frame plate structure made of stainless steel while supporting the frame plate;
A support member made of corrosion-resistant steel and supporting the fuel storage lattice;
A heat transfer block that is provided at the outer edge of the fuel storage lattice, is made of an aluminum alloy, and transmits decay heat generated from the spent fuel and transmitted through the fuel storage lattice to the spent fuel cask body;
And a spent fuel cask basket structure.

In the present invention, the frame plate of the fuel storage lattice includes a first frame plate and a second frame plate having a smaller size than the first frame plate,
The interframe structure between the fuel storage grids includes a first interframe structure and a second interframe structure smaller in size than the first interframe structure.
The first frame plate has a plurality of frame plate holes,
The first inter-frame plate structure has a plurality of inter-frame plate structure holes arranged to face the frame plate holes,
The second frame plate has a plurality of frame plate protrusions inserted into the frame plate hole and the inter-frame plate structure hole,
The second inter-frame plate structure has a plurality of inter-frame plate structure protrusions inserted into the frame plate hole and the inter-frame plate structure hole,
The second frame plate is fixed to the first frame plate and the first inter-frame plate structure by being inserted into the corresponding frame plate hole and the inter-frame plate structure hole corresponding to the frame plate convex portion,
The second inter-frame plate structure is inserted into the inter-frame plate hole portion and the inter-frame plate structure hole portion corresponding to the inter-frame plate structure convex portion, whereby the first inter-frame plate structure and the first inter-frame plate structure. A spent fuel cask basket structure characterized by being fixed to a body.

  The present invention is the spent fuel cask basket structure characterized in that the inter-frame structure of the fuel storage lattice includes a vertical member extending in the vertical direction and a transverse member extending in the horizontal direction. is there.

According to the present invention, the support member has an upper support plate having a loading hole into which spent fuel is inserted, a lower support plate that holds the fuel storage lattice from below, and a pipe shape that connects the upper support plate and the lower support plate. A rod-shaped connection member, a transverse support member coupled to the connection member and extending in the horizontal direction to support the fuel storage lattice; a longitudinal support member coupled to the transverse support member and extending in the vertical direction; Have
The spent fuel cask basket structure is characterized in that the support member is made of a corrosion-resistant material.

The present invention comprises a spent fuel cask body,
A basket structure that is arranged in the spent fuel cask body and constitutes a plurality of fuel storage chambers for storing spent fuel, and
The spent fuel cask body has a plurality of fixing members for fixing and positioning the basket structure on the inner surface,
The basket structure is
A fuel storage grid configured by superimposing a frame plate made of boron-added aluminum alloy and an inter-frame plate structure made of stainless steel while supporting the frame plate;
A support member made of corrosion-resistant steel and supporting the fuel storage lattice;
A heat transfer block that is brought into contact with the outer edge of the fuel storage lattice by the support member, is made of an aluminum alloy, and transmits decay heat generated from the spent fuel and transmitted through the fuel storage lattice to the spent fuel cask body; A spent fuel cask characterized by comprising:

  According to the present invention, a fuel storage lattice configured by superimposing a frame plate made of boron-added aluminum alloy and an inter-frame plate structure made of stainless steel while supporting the frame plate, and an outer edge of the fuel storage lattice With the heat transfer block made of aluminum alloy that is in contact with each other, the required amount of material can be greatly reduced while maintaining the shape of the grid assembly and the function of transferring heat to the cask. A basket structure with can be provided. Moreover, the spent fuel cask provided with the said basket structure can also be provided.

BEST MODE FOR CARRYING OUT THE INVENTION

First Embodiment Hereinafter, a first embodiment of a spent fuel cask basket structure according to the present invention will be described with reference to the drawings. Here, FIG. 1 to FIG. 4 are diagrams showing a first embodiment of the present invention.

  The spent fuel cask basket structure 50 of the present embodiment is arranged in the spent fuel cask main body and constitutes a plurality of fuel storage chambers R for storing spent fuel (see FIGS. 1 to 3). .

  As shown in FIGS. 1 to 3, a spent fuel cask basket structure 50 includes frame plates 4 and 6 (hereinafter referred to as B-Al frame plates 4 and 6) made of boron-added aluminum alloy, A fuel storage grid 1 (hereinafter referred to as a grid assembly 1) configured by superposing the inter-frame plate structures 3 and 5 made of stainless steel while supporting the B-Al frame plates 4 and 6; The assembly 1 is restrained and supported from the outside, and includes a support member 10 made of corrosion-resistant steel (hereinafter, referred to as a support unit assembly 10).

  Examples of the corrosion resistant steel used as the material for the support assembly 10 include stainless steel, low alloy steel, steel with a corrosion resistant film, and the like.

  As shown in FIGS. 1 and 2, the outer edge of the grid assembly 1 is made of an aluminum alloy, and decay heat generated from the spent fuel and transmitted through the grid assembly 1 is transmitted to the spent fuel cask body. A heat transfer block 30 for transmission is provided. The heat transfer block 30 is supported by a connecting member 12 of a support unit assembly 10 described later and is in contact with the lattice assembly 1 (see FIG. 3).

  As shown in FIGS. 1 to 3, the B-Al frame plates 4 and 6 of the lattice assembly 1 include a first frame plate 4 (hereinafter referred to as a B-Al frame plate (large) 4) and the B-frame. -It has the 2nd frame board 6 (henceforth B-Al frame board (small) 6) smaller than Al frame board (large) 4. As shown in FIGS. 1 to 3, the inter-frame plate structures 3 and 5 of the lattice assembly 1 are the first inter-frame plate structures 3 (hereinafter referred to as inter-frame plate structures (large) 3). And a second inter-frame plate structure 5 (hereinafter, referred to as an inter-frame plate structure (small) 5) that is smaller than the inter-frame plate structure (large) 3.

  As shown in FIGS. 3 and 4, the support assembly 10 includes an upper support plate 15 having a loading hole for inserting spent fuel, a lower support plate 16 that holds the lattice assembly 1 from below, and an upper support. A pipe-like or bar-like connecting member 12 that connects the plate 15 and the lower support plate 16; a transverse support member 14 that is coupled to the connection member 12 and extends in the horizontal direction and supports the lattice assembly 1; A longitudinal support member 13 connected to the member 14 and extending in the vertical direction.

  In addition, as shown in FIGS. 1 to 3, in the lattice assembly 1, the interframe structure (large) 3 and the interframe structure (small) 5 are in contact with the loaded spent fuel. A B-Al frame plate (large) 4 and a B-Al frame plate (small) 6 are provided, and the B-Al frame plate (large) 4 and the B-Al frame plate (small) 6 cover the wall surface of the fuel storage chamber R. It is composed.

  1 to 3, the inter-frame plate structure (large) 3 and the inter-frame plate structure (small) 5 are a B-Al frame plate (large) 4 and a B-Al frame plate (small) 6. It is installed in the space between the fuel storage chambers R which are divided so as to ensure the subcriticality while maintaining the gap size between the fuel storage chambers R.

  Next, the operation of the present embodiment having such a configuration will be described.

  As shown in FIGS. 1 to 3, the lattice assembly 1 has a skeleton (base) constituted by an interframe structure (large) 3 and an interframe structure (small) 5 made of stainless steel. So it has high strength.

  Further, as shown in FIGS. 1 to 3, since the lattice assembly 1 is supported and supported from the outside by a support assembly 10 made of corrosion-resistant steel, the overall shape of the lattice assembly 1 is maintained in a stable state. be able to.

  1 to 3, B-Al frame plate (large) 4 and B-Al frame plate (small) 6 are neutron absorbers containing boron. The gap between the fuel storage chambers R is maintained by the inter-frame plate structure (large) 3 and the inter-frame plate structure (small) 5, and the entire lattice assembly 1 is formed by the support assembly 10. Since the shape is maintained, it is possible to prevent the spent fuel stored in the fuel storage chamber R from becoming critical.

  1 to 3, a B-Al frame plate (large) 4, a B-Al frame plate (small) 6, an inter-frame plate structure (large) 3, and an inter-frame plate structure (small) 5 are shown. The grid assembly 1 constituted by the above members secures a heat transfer path.

  As shown in FIGS. 1 and 2, a heat transfer block 30 made of an aluminum alloy and in contact with the spent fuel cask body is provided on the outer edge of the lattice assembly 1. Therefore, the decay heat generated from the spent fuel can be transmitted to the spent fuel cask body via the grid assembly 1 and radiated to the outside.

  Conventionally, the space between the basket structure and the spent fuel cask body is filled with the support member to maintain the shape of the lattice assembly, and the decay heat from the spent fuel is used from the basket structure. It was transmitted to the fuel cask body.

  On the other hand, according to the present invention, as shown in FIG. 1 to FIG. 3, the shape of the grid assembly 1 is formed by the inter-frame structure 3, 5 made of stainless steel and the support assembly 10 made of corrosion-resistant steel. And the heat transfer block 30 can transmit decay heat from the spent fuel from the basket structure 50 to the spent fuel cask body.

  That is, according to the present invention, the inter-frame plate structures 3 and 5 and the support assembly 10 have the function of maintaining the shape of the lattice assembly 1, and the spent fuel is transferred from the basket structure 50 to the heat transfer block 30. The function of transferring heat to the cask body can be performed. As a result, the amount of material required to perform these functions can be greatly reduced, and a high-performance basket structure 50 can be obtained at low cost.

  By the way, as shown in FIG. 1 thru | or FIG. 3, in the lattice assembly 1, with respect to the spent fuel loaded with respect to the inter-frame-plate structure (large) 3 and the inter-frame-plate structure (small) 5 A B-Al frame plate (large) 4 and a B-Al frame plate (small) 6 are provided, and the B-Al frame plate (large) 4 and the B-Al frame plate (small) 6 cover the wall surface of the fuel storage chamber R. Since it is configured and arranged directly facing the spent fuel, high heat transfer performance can be realized.

  As shown in FIGS. 3 and 4, the support assembly 10 connects the upper support plate 15, the lower support plate 16 that holds the lattice assembly 1 from below, and the upper support plate 15 and the lower support plate 16. The connecting member 12 includes a horizontal support member 14 extending in the horizontal direction, and a longitudinal support member 13 extending in the vertical direction. The support assembly 10 is made of, for example, corrosion resistant steel such as stainless steel, low alloy steel, or steel with a corrosion resistant coating.

  For this reason, when manufacturing the support part assembly 10 of the basket structure 50, not only can the amount of expensive aluminum alloy used be significantly reduced, but also the support part assembly 10 having sufficient high-temperature strength and corrosion resistance is provided. be able to.

Second Embodiment Next, the second embodiment of the present invention will be described with reference to FIG. The second embodiment shown in FIG. 5 is a vertically extending longitudinal section in which the interframe structure (large) 3 satisfies the shape and dimensions appropriately calculated from the strength required for the basket structure 50. It consists of a member 41 and a transverse member 42 extending in the horizontal direction. In addition, the inter-frame plate structure (small) 5 also extends in the vertical direction and the longitudinal member 41 that satisfies the shape and dimensions appropriately calculated from the strength required for the basket structure 50 and in the horizontal direction. It consists of a transverse member 42. Other configurations are substantially the same as those of the first embodiment shown in FIGS.

  In the second embodiment shown in FIG. 5, the same parts as those in the first embodiment shown in FIGS.

  As shown in FIG. 5, the inter-frame plate structure (large) 3 and the inter-frame plate structure (small) 5 are composed of a longitudinal member 41 extending in the vertical direction and a transverse member 42 extending in the horizontal direction. It has become. For this reason, when the lattice assembly 1 is manufactured, the amount of stainless steel plate used for the interframe structure (large) 3 and the interframe structure (small) 5 can be reduced. 1 can be obtained.

Third Embodiment Next, a third embodiment of the present invention will be described with reference to FIG. In the third embodiment shown in FIG. 6, the B-Al frame plate (large) 4 has a plurality of frame plate hole portions 4a, and the inter-frame plate structure (large) 3 is a B-Al frame plate (large). ) It has a plurality of inter-frame plate structure hole portions 3a arranged to face the four frame plate hole portions 4a. The B-Al frame plate (small) 6 has a plurality of frame plate convex portions 6a inserted into the frame plate hole 4a and the inter-frame plate structure hole 3a, and the inter-frame plate structure (small). ) 5 has a plurality of inter-frame plate structure convex portions 5a inserted into the frame plate hole portion 4a and the inter-frame plate structure hole portion 3a. Other configurations are substantially the same as those of the second embodiment shown in FIG.

  In the third embodiment shown in FIG. 6, the same parts as those of the second embodiment shown in FIG.

  As shown in FIG. 6, by inserting the frame plate convex portion 6a of the B-Al frame plate (small) 6 into the corresponding frame plate hole portion 4a and the inter-frame plate structure hole portion 3a, the B-Al frame The plate (small) 6 can be fixed to the B-Al frame plate (large) 4 and the inter-frame plate structure (large) 3. Further, by inserting the inter-frame plate structure convex portion 5a of the inter-frame plate structure (small) 5 into the corresponding frame plate hole portion 4a and the inter-frame plate structure hole portion 3a, the inter-frame plate structure ( (Small) 5 can be fixed to the B-Al frame plate (large) 4 and the inter-frame plate structure (large) 3. Then, the basket structure 50 is configured by restraining the entire lattice assembly 1 combined in this way by the support assembly 10.

  For this reason, according to this Embodiment, when assembling the grid | lattice assembly 1, it is not necessary to use welding etc., and a quantity and an assembly man-hour can be reduced significantly. As a result, the lattice assembly 1 can be manufactured at a lower cost.

  Of course, when assembling the lattice assembly 1 from the B-Al frame plates 4 and 6 and the inter-frame plate structures 3 and 5, welding or mechanical tightening may be performed as necessary. By configuring the grid assembly 1 using such a method, a more stable basket structure 50 can be obtained.

Fourth Embodiment Next, a fourth embodiment of the present invention will be described with reference to FIG. The fourth embodiment shown in FIG. 7 is a spent fuel cask body 60 and a basket structure 50 that is arranged in the spent fuel cask body 60 and constitutes a plurality of fuel storage chambers R for storing spent fuel. And a spent fuel cask. Here, the spent fuel cask main body 60 has a plurality of fixing members 61 for fixing and positioning the basket structure 50 on the inner surface. The basket structure 50 has the configuration shown in the first embodiment.

  In the fourth embodiment shown in FIG. 7, the same parts as those in the first embodiment shown in FIGS.

  In FIG. 7, the fixing member 61 is firmly attached to the spent fuel cask main body 60 or formed by molding. Further, as shown in FIG. 7, the transverse support member 14 of the lattice assembly 1 adjacent to the spent fuel cask main body 60 is fixed and positioned. For this reason, it can prevent that the basket structure 50 rotates with respect to the spent fuel cask main body 60, and can prevent that the grating | lattice assembly 1 deform | transforms excessively.

  The fixing member 61 is disposed so as to be substantially uniform on the inner surface of the spent fuel cask main body 60. For this reason, when the spent fuel cask main body 60 supports the basket structure 50, the load applied to the spent fuel cask main body 60 can be uniformly distributed in various directions. As a result, the reliability of the spent fuel cask can be enhanced.

1 is a cross-sectional view of a spent fuel cask basket structure according to a first embodiment of the present invention. The enlarged view which expanded a part of FIG. The cross-sectional view which shows another cross section of the basket structure of the spent fuel cask by the 1st Embodiment of this invention. The side view of the basket structure of the spent fuel cask by the 1st Embodiment of this invention. The perspective view for demonstrating the assembly method of the basket structure of the spent fuel cask by the 2nd Embodiment of this invention. The perspective view of the basket structure of the spent fuel cask by the 3rd Embodiment of this invention. The cross-sectional view which shows the cross section of the spent fuel cask by the 4th Embodiment of this invention. The longitudinal section of the longitudinal section of the conventional basket structure and the spent fuel cask main body.

Explanation of symbols

1 Fuel storage grid (lattice assembly)
3 First interframe structure (frame structure (large))
3a Inter-frame plate structure hole 4 First frame plate (B-Al frame plate (large))
4a Frame plate hole 5 Second frame plate structure (frame plate structure (small))
5a Inter-frame plate structure convex part 6 Second frame plate (B-Al frame plate (small))
6a Frame plate convex part 10 Support member (support part assembly)
12 connecting member 13 longitudinal support member 14 transverse support member 15 upper support plate 16 lower support plate 30 heat transfer block 41 longitudinal member 42 transverse member 50 basket structure 60 spent fuel cask main body R fuel storage chamber

Claims (5)

In the basket structure that is arranged in the spent fuel cask body and constitutes a plurality of fuel storage chambers for storing spent fuel,
A fuel storage grid configured by superimposing a frame plate made of boron-added aluminum alloy and an inter-frame plate structure made of stainless steel while supporting the frame plate;
A support member made of corrosion-resistant steel and supporting the fuel storage lattice;
A heat transfer block that is provided at the outer edge of the fuel storage lattice, is made of an aluminum alloy, and transmits decay heat generated from the spent fuel and transmitted through the fuel storage lattice to the spent fuel cask body;
A spent fuel cask basket structure characterized by comprising: The frame plate of the fuel storage lattice has a first frame plate and a second frame plate having a smaller size than the first frame plate,
The interframe structure between the fuel storage grids includes a first interframe structure and a second interframe structure having a smaller size than the first interframe structure.
The first frame plate has a plurality of frame plate holes,
The first inter-frame plate structure has a plurality of inter-frame plate structure holes arranged to face the frame plate holes,
The second frame plate has a plurality of frame plate protrusions inserted into the frame plate hole and the inter-frame plate structure hole,
The second inter-frame plate structure has a plurality of inter-frame plate structure protrusions inserted into the frame plate hole portion and the inter-frame plate structure hole portion,
The second frame plate is fixed to the first frame plate and the first inter-frame plate structure by being inserted into the corresponding frame plate hole portion and the inter-frame plate structure hole portion, and the frame plate convex portion,
The second inter-frame plate structure is inserted into the inter-frame plate hole portion and the inter-frame plate structure hole portion corresponding to the inter-frame plate structure convex portion, whereby the first inter-frame plate structure and the first inter-frame plate structure. The spent fuel cask basket structure according to claim 1, wherein the basket structure is fixed to a body.   2. The spent fuel cask basket according to claim 1, wherein the inter-frame structure of the fuel storage lattice includes a vertical member extending in a vertical direction and a transverse member extending in a horizontal direction. Construction. The support member includes an upper support plate having a loading hole for inserting spent fuel, a lower support plate for holding the fuel storage grid from below, and a pipe-like or rod-like connection member for connecting the upper support plate and the lower support plate. And a transverse support member that is coupled to the connection member and extends in the horizontal direction and supports the fuel storage lattice, and a longitudinal support member that is coupled to the transverse support member and extends in the vertical direction.
The spent fuel cask basket structure according to claim 1, wherein the support member is made of a corrosion-resistant material. A spent fuel cask body,
A basket structure that is arranged in the spent fuel cask body and constitutes a plurality of fuel storage chambers for storing spent fuel, and
The spent fuel cask body has a plurality of fixing members for fixing and positioning the basket structure on the inner surface,
The basket structure
A fuel storage grid configured by superimposing a frame plate made of boron-added aluminum alloy and an inter-frame plate structure made of stainless steel while supporting the frame plate;
A support member made of corrosion-resistant steel and supporting the fuel storage lattice;
A heat transfer block that is brought into contact with the outer edge of the fuel storage lattice by the support member, is made of an aluminum alloy, and transmits decay heat generated from the spent fuel and transmitted through the fuel storage lattice to the spent fuel cask body; A spent fuel cask characterized by comprising:

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