JP6040335B1 - Fuel holder - Google Patents

Abstract

To provide a fuel holder capable of suppressing damage to the inner surface of a lodgement hole when being attached to and detached from a transport container. A fuel holder including a housing shell for housing a fuel assembly, wherein the housing shell includes a first half body and a second half body having two wall surface portions (11, 12, 21, 22) orthogonal to each other. A housing space is formed by the body, the top portion, and the bottom portion, the upper guide is provided on the wall surface portions 11 and 12 on the top portion side of the first half body, the lower roller is provided on the side surface on the first half body side of the bottom portion, Each of the wall surfaces 11, 12, 21, and 22 has a plurality of heat radiating windows 70, and the heat radiating windows 70 have chamfered outer peripheral edges 73 and 74. [Selection] Figure 5

Description

  The present invention relates to a fuel holder that accommodates a fuel assembly.

  Conventionally, when a nuclear fuel assembly for a nuclear reactor is transported, the nuclear fuel assembly is accommodated in a fuel holder, and the fuel holder is inserted into a plurality of lodge holes provided in a transport container and transported (Patent Document 1). And 2). More specifically, the fuel holder containing the nuclear fuel assembly is suspended vertically in the vertical direction, suspended and inserted into the lodgement hole. After that, the transport container is horizontally laid down and placed on the loading platform of a large vehicle for transportation. Since the transport container is transported sideways, the attached fuel holder has a biasing means for biasing the inner surface of the lodgement hole so as not to vibrate.

Japanese Patent No. 3080895 JP, 2006-040530, A

  However, since this biasing means is provided, the outer surface of the fuel holder and the inner surface of the lodgement hole may come into contact when the fuel holder is inserted (or removed) from the transport container. When the fuel holder is lowered or raised while being in contact with the inner surface of the logistics hole, contact marks or scratches are made on the outer surface of the fuel holder and the inner surface of the logistics hole, resulting in damage. In order to maintain the performance of the transport container, there has been a problem of checking the state of damage to the logic and repairing or replacing it as necessary.

  Then, this invention is made | formed in view of the said problem, and it aims at providing the fuel holder which can suppress that the inner surface of a lodgement hole is damaged at the time of insertion / extraction to a transport container.

(1) One aspect according to the present invention is a fuel holder including a housing shell for housing a fuel assembly, wherein the housing shell includes a first half body and a second half body having two wall surfaces perpendicular to each other. A housing space is formed by the half body, the top portion, and the bottom portion, and an upper guide is provided on the wall surface portion on the top portion side of the first half body, and a side surface on the first half body side of the bottom portion. Each of the wall surfaces has a plurality of heat radiating windows, and the heat radiating window has a chamfered outer peripheral edge.

(2) In the aspect of (1), at least a part of the heat dissipation window may be a parallelogram or a rectangle that is long in an axial direction connecting the top and the bottom.

(3) In the above aspect (1) or (2), the lower roller may be a bearing, and the bearing may be held by a roller shaft supported by elastic means.

(4) In any one of the above aspects (1) to (3), a plurality of the lower rollers may be held coaxially.

(5) In any one of the above aspects (1) to (4), the first half body and the second half body are connected to each other by a connecting means using a hinge so as to be opened and closed. The locking means may be locked to each other, and at least one of the coupling means and the locking means may be provided so as not to protrude from the outer surface of the housing shell.

(6) In any one of the above aspects (1) to (5), the bottom portion includes four side surfaces and a bottom surface that are orthogonal to each other. The two orthogonal side surfaces and the two orthogonal wall surfaces of the second halved body are formed by bending, and the remaining side surface and the bottom surface of the bottom portion are the first and second surfaces. It may be welded to the two halves.

  ADVANTAGE OF THE INVENTION According to this invention, the fuel holder which can suppress that the inner surface of a lodgement hole is damaged at the time of insertion / extraction to a transport container can be provided.

It is sectional drawing which shows the transport container 100 equipped with the fuel holder 1 which concerns on embodiment of this invention. It is explanatory drawing which shows the fuel holder 1 which concerns on embodiment of this invention. It is explanatory drawing which shows the bottom part. It is an expanded sectional view of the lower roller 60 cut | disconnected by the AA line of FIG. It is an expanded sectional view of the heat dissipation window 70 cut | disconnected by the CC line | wire of FIG. It is explanatory drawing which shows the modification of the thermal radiation window. It is an expanded sectional view of the fuel holder 1 cut | disconnected by the BB line of FIG. It is explanatory drawing which shows the connection means. It is explanatory drawing which shows the latching means. It is explanatory drawing which shows the locking hole 14a. 3 is a front view showing a locking pin 24. FIG. It is explanatory drawing which shows the holder 25. FIG.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. Note that the same reference numerals are given to the same elements throughout the description of the embodiment.

FIG. 1 is a cross-sectional view showing a transport container equipped with a fuel holder 1 according to an embodiment of the present invention.
As shown in FIG. 1, the fuel holder 1 is mounted in a rectangular lodge hole 101 provided in the transport container 100 and transported. The fuel holder 1 accommodates a fuel assembly (not shown) such as nuclear fuel for a nuclear reactor, for example, a mixed oxide fuel (MOX fuel). Note that the transport container 100 is laid down during transport, and is vertically oriented when the fuel holder is inserted or removed.

  FIG. 2 is an explanatory view showing the fuel holder 1 according to the embodiment of the present invention, and is (a) a front view, (b) a bottom view, (c) a right side view, and (d) a left side view.

  The fuel holder 1 shown in FIG. 2 includes a housing shell 2 that houses a fuel assembly. In the housing shell 2, the first half 10 and the second half 20, the top 30, and the bottom 40 form a housing space for housing the fuel assembly. The materials of the first half 10, the second half 20, the top 30, the bottom 40, etc. constituting the housing shell 2 have the required strength and heat resistance depending on the size and weight of the fuel assembly to be housed. Although it is selected as appropriate in consideration, it is usually a stainless steel such as SUS304 or a heat-resistant nickel-based alloy.

  The first halved body 10 has an L-shaped cross section formed by bending a single plate having a thickness of about 5 mm, and has two wall surface portions 11 and 12 that are orthogonal to each other (FIG. 2 ( d)). The wall surface portions 11 and 12 have an upper guide 50 on the top portion 30 side.

  The upper guide 50 is formed by a leaf spring in a circular arc shape or a tapered shape on the top 30 side in a side view. The upper guide 50 urges the fuel holder 1 against the inner surface of the logistics hole 101 of the transport container 100, thereby fixing the fuel holder 1 to the logistics hole 101 and preventing displacement due to vibration during transportation. ing. At this time, the first halved body 10 is inserted and mounted so as to be on the upper side of the lodgement hole 101 during transportation. Conversely, the second halved body 20 is inserted and mounted so as to be on the lower side of the lodgement hole 101 during transportation.

  Next, the second half 20 is an L-shaped section formed by bending a single plate material having a thickness of about 5 mm, like the first half 10, and two orthogonal Wall surface portions 21 and 22 (see FIG. 2D). A top portion 30 and a bottom portion 40 are attached to the second half body 20. Note that a top flange (not shown) that contacts the top surface of the lodgement hole 101 is provided on the top 30 side of the upper guide 50 on the wall surfaces 21 and 22 of the second half 20.

  The top portion 30 closes the upper portion of the fuel holder 1, and a hanging jig (not shown) such as an eyebolt or a hook is provided on the top surface. The top 30 is attached to the second half 20 by welding.

FIG. 3 is an explanatory view showing the bottom 40.
The bottom portion 40 includes four side surfaces 41 a, 41 b, 42 a, 42 b that are orthogonal to each other, and a bottom surface 43. Of these, the two orthogonal side surfaces 42a and 42b of the bottom 40 and the two orthogonal wall surfaces 21 and 22 of the second half 20 are integrally formed from a single plate material by bending. ing. The remaining side surfaces 41a and 41b and the bottom surface 43 of the bottom portion 40 are attached to the second half body 20 by welding.

  The bottom 40 may be formed in a box shape with the four side surfaces 41a, 41b, 42a, 42b and the bottom surface 43, and then attached to the second half 20 by welding. In this case, the welding mark is formed between the wall surface portions 21 and 22 on the opposite side of the lower roller 60 and the side surfaces 42a and 42b, and the possibility of contact with the inner surface of the lodgement hole 101 is increased. Post-treatment such as surface polishing is required.

FIG. 4 is an enlarged cross-sectional view showing the lower roller 60 cut along line AA in FIG.
The bottom 40 has a lower roller 60 on the side surfaces 41a and 41b on the first half body 10 side. The lower roller 60 urges the fuel holder 1 against the inner surface of the logistics hole 101 of the transport container 100 so that the fuel holder 1 is offset (fixed) to the logistics hole 101 and vibrates during transportation. This prevents misalignment.

  A bearing 61 is used for the lower roller 60. As shown in FIG. 4, a plurality of bearings 61 are held on a roller shaft 62 supported by the elastic means 63. However, the number of the bearings 61 is not limited to two, and may be three or more. Conversely, if the contact area contacting the inner surface of the lodgement hole 101 is equal, the number may be one.

  This is because the lower roller 60 is urged and brought into contact with the inner surface of the lodgement hole 101 by the elastic means 63 under a certain load condition. Although a load may be applied (unevenly), if a plurality of lower rollers 60 are held on the same axis, the load is distributed to the plurality of lower rollers 60. The contact between them is eased. In addition, the load can be dispersed by increasing the contact area (width) of the lower roller 60.

  By the way, a plurality of heat radiation windows 70 are formed in the wall surface portions 11, 12, 21, and 22 of the first half 10 and the second half 20. The heat radiating window 70 is for releasing decay heat due to nuclear fission of the fuel assembly accommodated in the fuel holder 1 and is formed in a square opening such as a square or a rectangle.

FIG. 5 is an enlarged cross-sectional view of the heat radiating window 70 cut along line CC in FIG. 2, and FIG. 6 is a plan view showing a modification of the heat radiating window 70.
The heat radiation window 70 has chamfered peripheral edges 73 and 74 at least on the outer surface on the top 30 side and the bottom 40 side. Further, it is preferable that the remaining peripheral edges 71 and 72 (in the front and back direction in FIG. 5) are also chamfered. The chamfering may be round chamfering (R chamfering) as shown in FIG. 5 (a) or square chamfering (C chamfering) as shown in FIG. 5 (b), but is preferably about 0.5 mm to 2.0 mm. Thereby, the heat radiating window 70 has no sharp part that damages the lodgement hole 101 in the insertion direction of the fuel holder 1.

However, the shape of the heat radiation window 70 is not limited to the above-described square such as a square or a rectangle.
For example, at least some or all of the plurality of heat radiating windows 70 are inclined with respect to a direction substantially orthogonal to the axial direction in which the peripheral edges 73 and 74 connect the top portion 30 and the bottom portion 40 as shown in FIG. Such a parallelogram opening may be provided. Thereby, since the direction orthogonal to the insertion direction of the fuel holder 1 does not coincide with the direction in which the peripheral edges 73 and 74 extend, even if the fuel holder 1 and the inner surface of the lodgement hole 101 come into contact, point contact is established.

  Further, the heat radiation window 70 closest to the top 30 side or the bottom 40 side may be formed in a rectangular opening that is long in the axial direction connecting the top 30 and the bottom 40 as shown in FIG. That is, the short sides are rectangular edges 73 and 74, and the long sides are rectangular edges 71 and 72. Since the opening area of the heat radiation window 70 is set by calculation from decay heat or the like, it cannot be reduced, but by making the heat radiation window 70 a rectangular opening that is long in the axial direction connecting the top portion 30 and the bottom portion 40, The strength in the axial direction connecting the top portion 30 and the bottom portion 40 of the fuel holder 1, that is, the buckling strength can be increased. Even if the heat radiating window 70 is drilled in the wall surface portions 11, 12, 21, and 22, the peripheral edges 73 and 74 are short, so the periphery of the heat radiating window 70 in the direction perpendicular to the insertion direction of the fuel holder 1 It does not happen to swell and deform.

  Next, the connecting means 3 and the locking means 4 will be described. FIG. 7 is an enlarged cross-sectional view of the fuel holder 1 taken along line BB in FIG. FIG. 8 is an explanatory view showing the connecting means 3, (a) a front view and (b) a right side view. FIG. 9A is an explanatory view showing the locking means 4, (a) a front view, (b) a right side, and (c) a top view. FIG. 9B is an explanatory view showing the locking hole 14a, (a) a front view and (b) a right side view. FIG. 9C is a front view showing the locking pin 24. FIG. 9D is an explanatory view showing the holder 25, (a) a front view, (b) a right side view, and (c) a top view.

  As shown in FIG. 7, the first half 10 and the second half 20 are connected to each other by the connecting means 3 so as to be opened and closed. Further, the first half 10 and the second half 20 are locked to each other by the locking means 4 so that the fuel holder 1 does not open during transportation or the like.

  A so-called hinge (hereinafter referred to as “hinge 3”) is used as the connecting means 3 for connecting the first half 10 and the second half 20. The hinge 3 is provided so as not to protrude from the outer surface of the housing shell 2. That is, the wall surface portions 11 and 21 are countersunk at a depth equal to or greater than the thickness of the slats of the hinge 3, and the hinge 3 is attached with a countersunk bolt or the like (see FIGS. 7 and 8). . Providing the hinge 3 in this way prevents the wall surfaces 11 and 21 from protruding from the outer surface.

  On the other hand, the locking means 4 for locking the first half 10 and the second half 20 moves to the second half 20 in the locking hole 14 a provided in the first half 10. The locking pin 24 that can be provided is locked so as to be locked (see FIG. 9A).

  Specifically, the locking hole 14 a is formed in the locking block 14 fixed to the inner surface side of the wall surface portion 12 (see FIG. 9B), and faces the tip of the locking pin 24. However, the locking hole 14a is located on the bottom portion 40 side, and the locking pin 24 is located on the top portion 30 side and faces each other.

  The locking pin 24 is provided so as to be movable with respect to the holder 25 fixed to the inner surface side of the wall surface portion 22 with a countersunk bolt or the like. An operation means 26 such as a bolt is attached to the locking pin 24 (see FIG. 9C).

  The holder 25 is formed with a hole 25a into which the locking pin 24 is movably inserted, and an elastic member 27 such as a coil spring is installed on the back side of the hole 25a. In addition, a groove 28 for guiding the shaft portion of the operating means 26 is formed in the holder 25 from the wall surface portion 12 side toward the wall surface portion 22. Specifically, the groove 28 has a groove 28a extending toward the front end direction (the direction of the locking hole 14a) of the locking pin 24 on the wall surface portion 22 side, and a front end direction of the locking pin 24 (on the wall surface portion 12 side). The groove 28b extends in the direction of the locking hole 14a and is longer than the groove 28a, and the groove 28c communicates with the groove 28a (see FIG. 9D).

  When the first half body 10 and the second half body 20 are to be locked using such a locking means 4, the operating means 26 is first positioned on the groove 28a side, and the locking pin 24 is pulled. Keep it in a packed state. Then, end faces opposite to the end faces of the first half 10 and the second half 20 connected by the connecting means 3 are butted together. Thereafter, when the operating means 26 is gripped and moved toward the groove 28b, the locking pin 24 to which the operating means 26 is attached is urged by the elastic member 27 and starts to protrude, and the locking hole 14a of the locking block 14 is started. Inserted and locked.

  At this time, that is, in the locked state of the first half 10 and the second half 20, the head of the operating means 26 does not protrude from the outer surface of the second half 20 (FIGS. 7 and 7). (See FIG. 9A). Further, since the locking pin 24 is urged by the elastic member 27, the locking pin 24 is not pulled out of the locking hole 14a due to vibration during transportation.

  Since the locking state between the locking hole 14a and the locking pin 24 is a relative relationship, the locking hole 14a is provided in the second half 20 and the locking pin 24 is connected to the first half. The body 10 may be provided.

  As described above, in the embodiment of the present invention, the fuel holder 1 includes the housing shell 2 that houses the fuel assembly, and the housing shell 2 includes the two wall surface portions 11, 12, 21, and 22 that are orthogonal to each other. An accommodation space is formed by the first half 10 and the second half 20, the top 30, and the bottom 40, and upper guides are provided on the wall portions 11 and 12 on the top 30 side of the first half 10. 50, and a lower roller 60 is provided on each surface of the bottom 40 on the side of the first half 10 and the wall surface portions 11, 12, 21, and 22 are provided with a plurality of heat radiating windows 70 so that heat is dissipated. The window 70 is characterized in that peripheral edges 71, 72, 73, 74 of the outer surface are chamfered.

  As a result, even if the fuel holder 1 comes into contact with the inner surface of the lodgement hole 101, there is no sharp part in the insertion direction of the fuel holder 1 that damages the lodgement hole 101. 1 and the damage to the inner surface of the lodgement hole 101 can be prevented.

  In the embodiment, the heat radiating window 70 is based on a quadrangle, so that the heat radiating window 70 can be easily drilled and chamfered.

  When the heat radiation window 70 is a parallelogram, even if the fuel holder 1 comes into contact with the inner surface of the lodge hole 101, it is not a surface contact or a line contact, but a point contact, so that it is difficult to get caught and easily Since the contact point can be passed, damage to the surface can be prevented.

  Further, when the heat radiation window 70 has a rectangular shape that is long in the axial direction connecting the top portion 30 and the bottom portion 40, the fuel holder 1 (housing shell) can be obtained without reducing the heat radiation performance with respect to the required opening area of the heat radiation window 70. 2) strength (buckling strength) can be increased.

  In the embodiment, the lower roller 60 is a bearing 61, and the bearing 61 is held by a roller shaft 62 supported by the elastic means 63. Thereby, even if it is non-uniform contact, the lower roller 60 does not become unrotatable with respect to the roller shaft 62, and the fuel holder 1 can be easily raised or lowered. There are no contact marks or scratches on the inner surface.

  In the embodiment, a plurality of lower rollers 60 are held coaxially. Thereby, even if it is non-uniform contact, a contact load can be disperse | distributed to two or more, the fuel holder 1 can be raised or lowered easily, and also a contact mark or a damage | wound is carried out to the inner surface of the logic hole 101. Is not attached.

  In the embodiment, the first half 10 and the second half 20 are connected to each other by the connecting means 3 so as to be openable and closable, and are locked to each other by the locking means 4. Thereby, since the fuel holder 1 (accommodating shell 2) can be manufactured mainly by bending, welding can be minimized and distortion due to welding can be prevented. Therefore, the dimensional accuracy of the fuel holder 1 can be improved, and the contact between the fuel holder 1 and the lodgement hole 101 can be made difficult to occur.

  In the embodiment, the connecting means 3 is a hinge 3, the hinge 3 is provided so as not to protrude from the outer surface of the housing shell 2, and the locking means 4 is a locking hole provided in the first half 10. 14a is engaged with a latch pin 24 that is movably provided in the second half 20 and is brought into a locked state, and the first half 10 and the second half 20 are locked. Then, it is provided so as not to protrude from the outer surface of the housing shell 2. Thereby, since the parts protruding from the fuel holder 1 (the housing shell 2) are only the upper guide 50 and the lower roller 60, damage due to other parts coming into contact with the inner surface of the lodgement hole 101 is prevented. Can do. In the embodiment, both the connecting means 3 and the locking means 4 are provided so as not to protrude from the outer surface of the housing shell 2, but at least one of the connecting means 3 and the locking means 4 is provided on the outer surface of the housing shell 2. By providing so that it may not protrude from, the components which protrude from the fuel holder 1 can be reduced even a little.

  In the embodiment, the bottom portion 40 includes four side surfaces 41a, 41b, 42a, and 42b that are orthogonal to each other, and a bottom surface 43, and the two side surfaces 42a and 42b that are orthogonal to the bottom portion 40 are formed from a single plate material. 42b and two orthogonal wall surfaces 21 and 22 of the second halved body 20 are formed by bending, and the remaining side surfaces 41a and 41b and the bottom surface 43 of the bottom 40 are formed by the second halves. It is welded to the body 20. Thereby, since the fuel holder 1 (accommodating shell 2) can be manufactured mainly by bending, welding can be minimized and distortion due to welding can be prevented. Therefore, the dimensional accuracy of the fuel holder 1 can be improved, and the contact between the fuel holder 1 and the lodgement hole 101 can be made difficult to occur. Moreover, since there is no welding mark on the second halved body 20 side, it is possible to prevent damage caused by contact of the welded portion.

  In the embodiment, the fuel assembly is accommodated in the fuel holder 1 and the fuel holder 1 is used. This ensures that the outer surface of the fuel holder 1 and the inner surface of the lodgement hole 101 are not contacted or scratched, and the state of damage to the lodgement hole 101 is confirmed to maintain the performance of the transport container 100. There is no problem of repair or replacement.

  In the embodiment, the fuel assembly is accommodated in the fuel holder 1, and the fuel holder 1 accommodating the fuel assembly is mounted in the rectangular lodgement hole 101 provided in the transport container 100 to transport the fuel assembly. This ensures that the outer surface of the fuel holder 1 and the inner surface of the lodgement hole 101 are not contacted or scratched, and the state of damage to the lodgement hole 101 is confirmed to maintain the performance of the transport container 100. There is no problem of repair or replacement. Further, during transportation, since the fuel holder 1 is urged against the inner surface of the lodgement hole 101 by the upper guide 50 and the lower roller 60, positional displacement due to vibration or the like does not occur, and surface damage can be prevented. .

  The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above-described embodiments, and various modifications may be made within the scope of the gist of the present invention described in the claims. It can be changed.

1 Fuel Holder 2 Housing Shell 3 Connecting Means (Hinges)
4 Locking means 10 1st half, 11, 12 Wall surface part 14 Locking block, 14a Locking hole 20 2nd half body, 21, 22 Wall surface part 24 Locking pin 25 Holder, 25a Hole, 26 Operation means 27 Elastic member 28, 28a 28b 28c Groove 30 Top 40 Bottom 41a 41b 42a 42b Side 43 Bottom 50 Upper guide 60 Lower roller 61 Bearing 62 Roller shaft 63 Elastic means 70 Heat radiation window 71 72, 73, 74 Perimeter edge 100 Transport container, 101 Lodiment hole

Claims (6)

A fuel holder comprising a housing shell for housing a fuel assembly,
The housing shell includes a first half and a second half having two orthogonal wall surfaces, a top, and a bottom formed by four side surfaces and a bottom perpendicular to each other. Is formed,
An upper guide on the wall portion on the top side of the first half;
A lower roller on each of the side surfaces of the bottom portion on the first half body side ,
The wall surface portion is provided with a plurality of heat radiating windows,
The heat radiating window has a peripheral edge of an outer surface thereof chamfered. 2. The fuel holder according to claim 1, wherein at least a part of the heat radiation window is a parallelogram or a rectangle that is long in an axial direction connecting the top portion and the bottom portion. The lower roller is a bearing;
The fuel holder according to claim 1 or 2, wherein the bearing is held by a roller shaft supported by an elastic means. The fuel holder according to any one of claims 1 to 3, wherein a plurality of the lower rollers are held coaxially with a roller shaft . The first half body and the second half body are connected to each other by a connecting means using a hinge so as to be opened and closed, and are locked to each other by a locking means,
5. The fuel holder according to claim 1, wherein at least one of the coupling unit and the locking unit is provided so as not to protrude from an outer surface of the housing shell. The second halved body is formed in a state in which one plate member is bent, with the two wall surface portions orthogonal to each other and the two side surfaces orthogonal to the bottom portion .
The fuel holder according to any one of claims 1 to 5, wherein the remaining side surface and the bottom surface of the bottom portion are welded to the second halved body.

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