JPH0132480B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a container for containing radioactive material within a cask. More specifically, the present invention provides an inner container for a transport cask that can be taken in and taken out through a sealable connecting part provided in a sampling bench or glove box, that is, a "gamma gate".

Containers for transporting radioactive materials include casks for transporting spent nuclear fuel removed from nuclear reactors, casks for transporting radioactive waste, containers contaminated with radioactivity, and transport for transporting equipment parts to and from sampling benches or glove boxes. There is a container called a cask.

In particular, when transporting radioactive waste or containers or equipment contaminated with radioactivity, these materials are stored in a cask container in advance.

When radioactive waste or radioactively contaminated materials stored in the sampling bench etc. are taken in or out, the contents of the cask are normally removed through a sealable opening and closing part called a "γ gate" installed in the sampling bench. We are transporting the equipment. In any case, when carrying equipment into or out of a sampling bench, etc., the equipment should be placed in a container to prevent radioactive contamination. It is necessary to accommodate it inside.

FIG. 1 is a cross-sectional view showing a conventional cask inner container, etc., in which a γ gate 2 is provided on the bottom surface of a sampling bench 1 (only a part of the bottom of the sampling bench is depicted in the drawing), and this γ
The gate 2 and the upper part are connected to an opening 4 provided at the bottom of an inner box 3 located inside the sampling bench 1.

Reference numeral 5 denotes a transport cask, which has a housing part 7 formed inside it surrounded by a shield 6 that shields radioactivity;
Further, a cushioning material 8 is provided on the outer surface of the shield 6. The opening at the top of the transportation cask 5 is configured to be closable with a lid 9 indicated by a two-dot chain line.

Now, as shown in FIG. 1, a cask inner container 10, which is the object of the present invention, is housed in a housing section 7 provided at the center of the transportation cask 5.

Next, to explain specifically how to use the device, the transport cask 5 containing the cask inner container 10 is carried by a trolley or the like to the lower part of the γ gate 2 provided at the bottom of the sampling bench 1,
Here, the lid part 9 provided on the upper part of the transport cask 5 is removed, and the cask inner container 10 is moved to the inner box 3 of the γ gate 2 by an externally operated pandagraph type lifting device 11 (hydraulic cylinder type lifting device, etc.). The lid 13 of the inner container 10 and the lid 12 of the γ gate 2 are combined and integrated into one body, and the lid 13 of the inner container 10 and the lid 12 of the γ gate 2 are pushed up to the lid 12 provided in the opening 4 provided at the bottom of the (In the case of a sampling bench with this structure, the operation part 15
).

Here, using tongs or the like in the sampling bench 1, the object is transferred to the inner container 10 from which the lid 13 has already been removed by the above operation, or the object is taken out from the inner container 10.

After loading and unloading the items, the lid 12 of the γ gate 2 holding the lid 13 of the inner container 10 is closed again, and the lid 13 of the inner container 10 is removed from the lid 12 of the γ gate 2 by remote control. , then the lifting device 1
1, the inner container 10 is lowered and housed in the transport cask 5, and the lid 9 of the transport cask 5 is closed and transported outside using a cart or the like.

However, when the opening of the γ gate 2 is connected to the opening 4 of the sampling bench 1 as shown in FIG. becomes. For this reason, when a gripping and carrying device such as tongs provided on the sampling bench is operated to take out an object from the inner container 10 or to store it in the transportation device 10, the peripheral wall of the inner container becomes an obstacle, making it difficult to operate the tongs. There were flaws that worsened.

To be more specific, in a container where the bottom part is integrally provided at the bottom of the peripheral wall, such as a normal container, when an object is stored in a state where it does not protrude from the opening at the top of the peripheral wall, this is the case. To grasp an object, insert the claw part of the tongs into the inner container from above,
It is necessary to grasp the object with these claws and lift it up. Further, if there is a small gap between the object housed in the inner container and the inner surface of the peripheral wall of the container, the claws cannot penetrate into the gap, so the claws can It is substantially difficult to grasp an object, and moreover, it is difficult to grasp an object from inside the inner container 10 by visual inspection or by remote control. This is because the inner container 10 has a high peripheral wall.

The present invention aims to eliminate the drawbacks of the conventional inner container, and provides a container to be housed in a transport cask, which includes a peripheral wall portion having an upper opening and a lower opening; The container includes a lid for closing the opening, and a bottom, the bottom being separate from the peripheral wall and airtightly joined to the edge of the lower opening by an elastic member. a pushing device for pushing up the container to a position where the peripheral wall portion exceeds the end of the γ gate; and a pushing device for pushing the container up to a position where the contents on the bottom portion can be gripped without inserting a gripping tool into the container after the lid portion is removed. The present invention is characterized by comprising a push-up device for raising the bottom portion within the peripheral wall portion.

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 2 is a partial sectional view of the inner cask container for transportation according to the present invention, in which an opening 22 is formed at the lower part of the peripheral wall 21 of the inner cask container 20, and an edge 23 at the lower part of the peripheral wall 21. One end of a bellows 24, which is a type of extensible body, is fixed to the bellows 2.
A bottom portion 25 is fixed to the other end of 4. A lid 27 is provided for closing the housing portion 26 surrounded by the peripheral wall portion 21. This lid body 27
An engagement alloy 28 that engages with the lid of the γ gate is fixed at the center of the gate.

A feature of the cask inner container 20 according to the present invention is that the peripheral wall portion 21 and the bottom portion 25 are constructed separately, and the space between the bottom portion 25 and the peripheral wall portion 21 is airtight with an elastic body, for example, a bellows 24. are joined,
Therefore, the bottom portion 25 is configured to be able to rise within the peripheral wall portion 21.

The bellows 24 is generally preferably made of metal from the viewpoint of radiation resistance and strength, but if high temperatures do not work, the bellows may be made of synthetic resin. Further, as described above, a bellows is most suitable as the extensible body, but it is also possible to adopt a structure that can form a seal such as a combination of a piston and a cylinder, and further allows movement between the two.

Next, the operation of the cask inner container according to the present invention will be explained.

FIG. 3 is a sectional view showing the state in which the cask inner container 20 is used, and shows a state in which the equipment 35 housed in the cask inner container 20 is pushed up to be supported by the tongue claws.

The equipment 35 is housed in the cask inner container 20, and the lower part of the edge 23 of the cask inner container 20 is supported by a pushing device 39 (a pantograph type device is shown in FIG. 1) to open the γ gate. 2, the upper part of the protrusion part 38 provided on the surface of the peripheral wall part 21 comes into contact with the protrusion part 37 formed inside the upper end of this γ gate 2, and the inner container 20 rises. The portion 21 extends beyond the end of the γ gate 2. Here, after removing the γ gate and the lid of the inner container, the bottom 25 of the cask inner container 20 is
When the push-up device 36 moves up, the bottom part 25 moves up while stretching the bellows 24, leaving the peripheral wall part 21 intact.

As the bottom portion 25 rises, the equipment 35 placed on the bottom portion 25 protrudes from the upper end of the peripheral wall portion 21. In this state, the side surface of the device 35 can be easily gripped by the claws at the tips of the tongs.

In the present invention, as described above, it is important that the equipment 35 placed on the bottom part 25 rises as the bottom part 25 rises.
Not only can the tongs 5 be easily grasped by the claws as described above, but it is also possible to operate the tongs while visually observing the device 35 from the top or side.

Further, since the claw portion at the tip of the tongs is not inserted into the inner container 20, the peripheral wall portion 21 of the container
There is no need to consider the size of the gap between the container and the equipment 35, and it is possible to store large objects or small objects that could not be accommodated in conventional cask inner containers.

As described above, in the transport cask inner container according to the present invention, the bottom part and the peripheral wall part are separated, the two are airtightly joined by the elastic body, and the bottom part can be moved up and down with respect to the peripheral wall part. Therefore, even if equipment or radioactive waste is placed on a flat plate, it is possible to store it or take it out with a simple movement of tongs, making it possible to safely and accurately manipulate hazardous materials. It is possible.

Further, the cask inner container according to the present invention can be used as is in a conventional transportation cask, sampling bench, or glove box.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part showing a mechanism for taking things in and out of the sampling bench. FIG. 2 is a sectional view of a main part showing a schematic structure of the inner cask container for transportation according to the present invention, and FIG. 3 is a diagram showing the state of use of the inner cask container. 1... Sampling bench, 2... γ gate,
3... Inner box, 4... Opening, 5...
Cask, 6... Radioactivity shield, 10... Cask inner container, 11... Lifting device, 12... γ gate lid, 13... Inner container lid, 14... Remote device, 20... Cask inner container, 21...peripheral wall part,
22... Opening, 23... Edge, 24... Expandable body (bellows), 25... Bottom plate, 26... Accommodating part, 2
7... Lid of inner container, 28... Engagement alloy, 35...
...equipment, 36...pushing device, 37...projection, 3
8...Protrusion section.

Claims (1)

[Scope of Claims] 1. A container housed in a transport cask, which comprises a peripheral wall portion having an upper opening and a lower opening, a lid portion for closing the upper opening, and a bottom portion, the bottom portion being The container is separated from the peripheral wall portion and is airtightly joined to the edge of the lower opening by an elastic body, and the container is equipped with a push-up device for pushing the container up to a position where the peripheral wall portion exceeds the end of the γ gate. and a push-up device that lifts the bottom within the peripheral wall to a position where the contents on the bottom can be grasped without inserting a gripping tool into the container after the lid is removed. Cask inner container for transportation. 2. The cask inner container for transportation according to claim 1, wherein the expandable body is a metal bellows.