JP2020115084A - Method for transporting radioactive material storage container - Google Patents

Abstract

To improve the earthquake resistance of a lifting machine for transporting a radioactive material storage container, in addition to preventing the storage container from falling over upon transporting the storage container.SOLUTION: A method for transporting a storage container for storing radioactive material, comprises: a first step of transporting the storage container from a horizontal frame in a first area to a stand-up frame in a second area; a second step of standing up the storage container from a horizontal state to a vertical state in the second area; and a third step of transporting the storage container from the stand-up frame in the second area to a vertical frame in a third area. The second step is performed between side walls provided close to the stand-up frame.SELECTED DRAWING: Figure 3

Description

TECHNICAL FIELD The present invention relates to a method of transporting a radioactive substance storage container that stores a radioactive substance such as a spent fuel assembly or radioactive waste.

The fuel used in the core of the nuclear power generation facility for a certain period of time is taken out from the core and stored in a storage container, then transported to a spent fuel storage facility inside or outside the nuclear power generation facility and temporarily stored.

An example of such a storage facility is the spent fuel storage facility of Patent Document 1. In Patent Document 1, as a configuration of a spent fuel storage facility, "a storage area for loading and unloading a spent fuel storage container from a trailer and a storage area for storing the spent fuel storage container from the carry-in area It is roughly composed of an area and the loading area, which has an overhead crane at the top and a building frame around it, and the storage area needs to be cooled naturally by circulating the spent fuel storage container. An air vent and an exhaust vent are provided."

When carrying a storage container into the storage facility, the storage container in the lying-down state is unloaded from the trailer in the carry-in area of the storage facility, vertically erected and then transported to the storage area. A hoisting machine typified by an overhead crane is often used in these processes, but in the process of raising the storage container, the storage container is raised by using two points on one end side of the storage container as support points. Compared to other processes that use four points as support points, the probability of falling of the storage container is increased because there is no backup function when the lifting device is detached.

Therefore, a transport method for suppressing damage to the storage container and the radioactive material contained therein due to the storage container falling or falling is also proposed. For example, in the cask carry-in device of Patent Document 2, the storage container is not greatly separated from the floor surface as compared with the case where the storage container is lifted up and transported by a crane, and therefore the storage container is also fallen or dropped. It reduces the degree of damage.

JP, 2014-25840, A JP, 2009-204515, A

However, in the cask carry-in device of Patent Document 2, when the storage container falls due to detachment of the suspending tool or the like, it is difficult to predict the falling direction of the storage container because the falling direction is determined by the degree of detachment of the suspending tool. Is.

Therefore, in the present invention, when the storage container falls during the process of raising the storage container by a lifting device such as a crane, the falling direction can be limited, and the impact when the storage container falls can be suppressed. The purpose is to provide a method of transporting a radioactive substance storage container.

A method of transporting a storage container for storing a radioactive substance, comprising the first step of transporting the storage container from a horizontal mount in the first area to a stand up stand in the second area, and the storage container in the second area. There is a second step of standing up from a horizontal state to a vertical state, and a third step of transporting the storage container from a standing stand in a second area to a vertical stand in a third area, and the second step, It is carried out between the standing upright and the side wall provided in the vicinity thereof.

According to the present invention, during the process of raising the storage container by a lifting device such as a crane, when the storage container falls, the falling direction can be limited, and the impact at the time of dropping the storage container can be suppressed. A method of transporting a storage container can be provided.

External view of radioactive material storage container The side view explaining the carrying method of Example 1 in the carry-in area. Side view explaining the raising process of the storage container in the second area The top view explaining the carrying method of Example 1 in a carrying-in area. The side view explaining the carrying method of Example 2 in the carry-in area. A side view explaining a transportation method of Example 3 in a carry-in area A perspective view for explaining a carrying method of the third embodiment in a carry-in area Perspective view of a conventional lifting device A perspective view of a lifting device according to a fourth embodiment.

Embodiments of the present invention will be described below with reference to the drawings.

First, a method for transporting a radioactive substance storage container according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 3.

FIG. 1 is an external view of a radioactive substance storage container (hereinafter referred to as “storage container 1”) according to the present embodiment. This storage container 1 is a substantially cylindrical container that contains radioactive substances such as spent fuel assemblies and radioactive waste inside, and is equipped with a total of eight trunnions 1a on the outer circumference of the upper and lower ends of the cylinder. The upper opening is closed by the lid 1b. The storage container 1 containing a radioactive substance and having a weight of about 130 to 150 tons is lifted by a lifting machine described later via a lifting tool attached to the trunnion 1a, and transported to a desired place.

2A, 2B, and 3 are a side view and a plan view illustrating a method of transporting the storage container 1 at the entrance of the storage facility (hereinafter, referred to as a “loading area”). The storage facility is a facility for storing the storage container 1 transported from the outside, and is mainly divided into a carry-in area and a storage area. The carrying step shown in the figure is a step before the step of carrying the storage container 1 from the carry-in area to the storage area, and is a step of vertically raising the horizontally-oriented storage container 1 in the carry-in area.

As shown in these figures, in the present embodiment, the carry-in area is divided into three areas: the first area 3, the second area 4, and the third area 5. The first area 3 is a stop area where the trailer 2 on which the storage container 1 is placed stops, the second area 4 is a work area where the horizontally oriented storage container 1 is oriented vertically, and the third area 5 is a vertical orientation. It is a temporary storage area for storing the storage container 1 until it is transported to the storage area. Hereinafter, the carrying process of the present embodiment will be described by subdividing each area.
<Transportation process from the first area 3 to the second area 4>
As shown in FIG. 2A, the storage container 1 is placed on the horizontal mount 2a on the loading platform of the trailer 2 parked in the first area 3 in a posture with the longitudinal direction horizontal (horizontal state). The horizontal mount 2a holds a total of four trunnions 1a, which are a pair of upper side and a lower side of the storage container 1, so that the trailer 2 can move the storage container 1 in the front-rear and left-right directions. It is restricted.

A lifting machine 6 is used to transport the storage container 1 from the first area 3 to the second area 4. First, in the first area 3, the four trunnions 1a on the side of the storage container 1 and the hoisting machine 6 are connected via a lifting tool. Then, the hoisting machine 6 hoists the storage container 1 in the horizontal state, and places the storage container 1 in the horizontal state on the raising/lowering stand 8 installed in advance in the second area 4. The upright stand 8 holds a total of four trunnions 1a, which are the upper pair and the lower pair, of the storage container 1, like the horizontal stand 2a.
<Rising process in the second area 4>
In the second area 4, the hoisting machine 7 is used to stand up the storage container 1 in a horizontal state such that the longitudinal direction is in a vertical posture (vertical state). First, as shown in the left diagram of FIG. 2B, the upper pair of trunnions 1 a of the storage container 1 and the pair of arms of the lifting machine 7 are connected. When the lifting machine 7 is lifted in this state, the storage container 1 gradually approaches the vertical direction with the pair of lower trunnions 1a held by the upright stand 8 as a fulcrum, as shown in the center view of FIG. 2B. Then, as shown in the right diagram of FIG. 2B, after the storage container 1 becomes vertical, another pair of trunnions 1 a on the upper side of the storage container 1 and another pair of arms of the lifting machine 7 are connected. Thereby, the storage container 1 and the lifting machine 7 can be connected at four points.
<Transportation process from the second area 4 to the third area 5>
The lifting machine 7 is continuously used to transport the storage container 1 from the second area 4 to the third area 5. At this point, since the storage container 1 and the lifting machine 7 are connected at four points, the lifting machine 7 can lift the storage container 1 in a stable posture. After that, the lifting machine 7 places the storage container 1 in the vertical state on the vertical mount 9 installed in advance in the third area 5.

Here, as shown in FIG. 2A, in the carry-in area of this embodiment, the first area 3 and the second area 4 have the same height, while the third area 5 is higher than both areas. .. Specifically, the height of the third area 5 is substantially the same as the height of the upper end of the upright stand 8 installed in the second area 4. By designing the carry-in area in this way, the height of the storage container 1 from the floor of the lower end of the storage container 1 and the third area 5 when the storage container 1 stands up and moves horizontally from the mount 8 to the vertical mount 9. Therefore, even if the storage container 1 is dropped, the degree of damage to the storage container 1 can be reduced.
<Sidewall of second area 4>
Next, the side wall provided in the second area 4 of this embodiment will be described with reference to FIG. FIG. 3 is a plan view of FIG. 2A seen from above, and a cross-sectional view taken along the line AA of FIG. 3 corresponds to FIG. 2A.

As shown in FIG. 2A, the connection of the storage containers 1 in the carrying process by the lifting machine 6 and the connection of the storage containers 1 in the carrying process by the lifting machine 7 are all four-point support. Therefore, even if the connection is broken at one point, the remaining three points are still connected and the storage container 1 does not drop. However, as shown in FIG. 2B, in the process of raising the storage container 1, the lifting machine 7 and the storage container 1 are connected to each other at two points, so even if one point is disconnected, the storage container is directed in that direction. 1 may fall and fall on the floor, and the storage container 1 may be damaged.

Therefore, in the second area 4 of this embodiment, a flat side wall that narrows the width of the second area 4 is provided so as to be close to the upright stand 8. As a result, even if one of the two-point connection between the lifting machine 7 and the storage container 1 is disconnected and the storage container 1 is tilted in that direction, the tilted storage container 1 is supported by the side wall and the storage container 1 By controlling the falling direction, it is possible to prevent the storage container 1 from falling from the upright stand 8 onto the floor, so that the storage container 1 can be prevented from being damaged. It is more desirable that the side wall is provided with a cushioning body for mitigating the collision of the storage container 1.

As described above, according to the method of transporting the radioactive substance storage container of the present embodiment, since the side wall is provided in the second area 4, the lifting machine 7 and the storage container 1 are disconnected, and the storage container 1 tilts. Even in such a case, the falling direction of the storage container 1 can be controlled to prevent the storage container 1 from falling onto the floor. Further, since the third area 5 is made higher than the first area 3 and the second area 4, when the storage container 1 stands up and moves horizontally from the mount 8 toward the vertical mount 9, the storage container 1 should be Even if the storage container 1 is dropped, the height of the third area 5 from the floor surface can be reduced, so that the degree of damage to the storage container 1 can be reduced.

Next, a method of transporting a radioactive substance storage container according to the second embodiment of the present invention will be described with reference to FIG. It should be noted that redundant description is omitted for the common points with the first embodiment.

In the first embodiment, the first area 3 and the second area 4 have the same height, but in the second embodiment, the first area 3 is lower than the second area 4. Specifically, the upper end of the horizontal mount 2a on the trailer 2 and the upper end of the stand-up mount 8 installed in the second area 4 have substantially the same height. As a result, the lifting height (the amount of vertical movement) of the storage container 1 in the transportation process from the first area 3 to the second area 4 can be made smaller than that in the first embodiment.

Since the lifting machine 6 lifts the storage container 1 of 130 to 150 tons, the lifting machine 6 is required to have a high earthquake resistance strength as compared with a general lifting machine. By reducing the lifting height as in this embodiment, it is possible to lower the center of gravity of the lifting machine 6 when the storage container 1 is lifted. Therefore, there is a requirement for the seismic strength design of the building in which the lifting machine 6 is installed. Can be relaxed.

Next, a method for transporting a radioactive substance storage container according to the third embodiment of the present invention will be described with reference to FIGS. It should be noted that duplicated description will be omitted for common points with the above-described embodiment.

In the first and second embodiments, the side wall of the second area 4 is made flat, but in the present embodiment, as shown in the sectional view of FIG. 5 and the perspective view of FIG. Ribs 4a are provided on the entire circumference of the upper part of the. In this way, by using the side wall having the rib 4a on the upper portion, it is possible to limit the location where the storage container 1 receives an impact when the storage container 1 falls over to the rib 4a. In particular, if the rib 4a is provided with a cushioning material such as wood, it is possible to further reduce the impact due to the collision when the storage container 1 falls. The lower part of the rib 4a can also be utilized as a work space.

Next, a method of transporting a radioactive substance storage container according to the fourth embodiment of the present invention will be described with reference to FIG. It should be noted that duplicated description will be omitted for common points with the above-described embodiment.

First, a conventional lifting device will be described with reference to FIG. Conventionally, in each of the first area 3 to the third area 5 of the carry-in area, the installation location of the gantry has not been specified, so that the storage container 1 on the gantry installed at an arbitrary location in a certain area can be There was a need for a lifting device that could be carried on a stand installed anywhere in the area. Therefore, as shown in FIG. 7, for example, a conventional lifting device has a pair of rails 10 installed in parallel, a pair of saddles 11 arranged on the pair of rails 10, and a space between the pair of saddles 11. The garter 12 arranged on the garter 12, the trolley 13 arranged on the garter 12, the winding machine 14 arranged in the trolley 13, and the storage container gripping tool 15 arranged below the winding machine 14. The vertical transport of the storage container 1 is performed by winding the wire of the winder 14, and the transport of the storage container 1 in the transport direction and the transverse direction is performed by driving the wheels of the saddle 11 and the trolley 13.

On the other hand, as shown in FIG. 3, when the horizontal mounts in the first area, the upright mounts in the second area, and the vertical mounts in the third area are arranged in a substantially straight line, The apparatus need only carry the storage container 1 in the carrying direction, and need not carry it in the transverse direction. Therefore, in the lifting devices 6 and 7 of the present embodiment, as shown in FIG. 8, the rail 10 is arranged in parallel with the carrying direction, the trolley 13 used for carrying in the transverse direction is omitted, and the winder 14 is provided. Was fixed at the approximate center of the garter 12, which is at a lower position than the conventional one.

As described above, in the lifting device of the present embodiment, the carrying direction of the storage container 1 is limited to one horizontal direction, so that the structure can be simplified as compared with a conventional lifting machine that is capable of carrying in two horizontal directions. As a result, the weight of the lifting machine can be reduced, the center of gravity of the lifting machine can be lowered, and the seismic strength of the lifting machine can be further increased. Further, as in the present embodiment, it is possible to relax the requirement for the seismic strength design of the building in which the lifting machine 6 is installed.

It should be noted that the present invention is not limited to the above-described embodiments, but includes various modifications. The above-described embodiments have been described in detail in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the configurations described.

1 storage container,
1a trunnion,
1b lid,
2 trailers,
2a Horizontal mount,
3 first area,
4 second area,
5 Third area,
6, 7 hoist,
8 stand up stand,
9 Vertical mount,
10 rails,
11 saddles,
12 Garter,
13 Trolley,
14 Winding machine,
15 Storage container gripping tool

Claims (6)

A method of transporting a storage container for storing radioactive material, comprising:
A first step of transporting the storage container from the horizontal mount in the first area to the stand up stand in the second area,
A second step of raising the storage container from a horizontal state to a vertical state in the second area,
It has a third step of transporting the storage container from the stand up stand in the second area to the vertical stand in the third area,
The method of transporting a storage container, wherein the second step is performed between a side wall provided close to the upright stand. The method of transporting a storage container according to claim 1,
A method of transporting a storage container, wherein a buffer is provided on the side wall. The method of transporting a storage container according to claim 1,
A method of transporting a storage container, characterized in that a rib is provided on an upper portion of the side wall. The method of transporting a storage container according to claim 1,
The storage container transportation method, wherein the third area is located higher than the second area. The method of transporting a storage container according to claim 4,
The method of transporting a storage container, wherein the second area is higher than the first area. The transport method according to any one of claims 1 to 5,
The method of transporting a storage container, wherein the horizontal mount in the first area, the stand-up mount in the second area, and the vertical mount in the third area are linearly arranged.

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