JPH0567199B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a radiation shielding device provided within a cell box.

Prior Art Conventionally, in a cell box where experiments and the like are conducted, the removal of experimental equipment after use is carried out remotely using a manipulator, an in-cell crane, etc., and the entire equipment is replaced. However, in recent years, in order to use experimental equipment more efficiently, it has become necessary to replace only certain parts, and it has become necessary to disassemble and remove equipment that produces high radiation doses within the cell. However, the capabilities of manipulators and the like within the hot cell are limited, and it is especially impossible to remove firmly screwed screws, so some work must be done manually through the cell port. Therefore, shielding is required to reduce the radiation exposure of these workers.

Problems to be Solved by the Invention Generally, a plate made of lead and having a predetermined thickness is used as a radiation shield. However, when a worker installs the shielding device inside the cell at the cell port, he or she is exposed to a high dose of radiation and exposed to radiation-contaminated air. The shielding device must be installed within a limited grasping capacity and movable range, and after installation, the shielding body of the shielding device must be able to be disassembled and moved in order to carry contaminated parts out of the cell.
Therefore, heavy lead plates cannot be used.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and provide a radiation shielding device that can be installed and removed within the capacity of a manipulator provided in a cell and has sufficient shielding ability.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a pair of shielding supports that are erected at positions facing the cell port in a cell at a predetermined interval, and a shielding support that can be raised and lowered on these shielding pillars. A body receiving seat is provided, a spring is provided that biases this shielding body receiving seat upward, and the biasing force of this spring is applied to the shielding members stacked in accordance with the number of shielding members having a mountain-shaped cross section stacked on the shielding body receiving seat. The upper end of the shielding member is set so that it is always at a substantially constant level.

Effect In the above configuration, when the shielding members are piled up one by one using the manipulator on the shielding seat which is biased upward by the spring and is at a certain level, the shielding seat is kept at a constant level due to the weight of the shielding member. The upper ends of the shielding members that are lowered by a distance along the shielding support column and stacked on the shielding seat are located within the operating range of the manipulator while maintaining a substantially constant level or higher depending on the number of the shielding members. Therefore, the manipulator can be used to install or remove the shield even below the manipulator's operating range. Furthermore, radiation is reliably blocked by the stacked shielding members having a mountain-shaped cross section without passing through gaps between the shielding members.

Embodiment An embodiment of the present invention will be described below based on the drawings.

In Figures 1 to 4, 1 is cell box 2.
It is a component transport rail arranged inside the cell port 3 on the back side of the cell port 3 along the opening surface of the cell port 3, and is supported by a pair of rail supports 4 arranged at positions substantially opposite to each other at both left and right ends of the cell port 3. be done. 5 is a radiation shielding device provided inside the rail 1 facing the cell port 3, which includes a shield body 6 arranged parallel to the rail 1, and a shield body supporting this shield body 6 from below. It consists of a seat 7 and a pair of guide parts 8 that guide and support the shield body 6 and the shield seat 7 at both ends.

The guide portion 8 includes a substrate 9 disposed with a concave corner portion 9a engaged with each rail support 4;
A pair of shield support columns 10 are erected on the base plate 9 and are located outside both left and right ends of the shield body 6; guide column 11A, 1
1B, and an auxiliary support post 12 which is erected on the base plate 9 and is placed closer to the center between the shield main body 6 and the rail 1 with some spacing from the outer guide support post 11A. The shield support 7 is attached to the shield support 10.
The through-holes 7a at both ends of the through-holes 7a are attached to the shield supports 10 so as to be able to rise and fall freely, and between the shield receivers 7 and the base plate 9, there are coil springs 13 that are fitted around the shield supports 10. It is interposed and urges the shield receiving seat 7 upward. The above guide columns 11A, 11B
is separably connected to the lower guide column 11a and the upper guide column 11b at the center via the connecting portion 11c, and the upper end portions of the upper guide columns 11b are curved and spread outward from the shield body 6, and the shield Guide the insertion of the main body 6. An abutment plate 14 is erected at one end of the shield receiving seat 7 for regulating the limit of lateral movement of the shield main body 6.

The above outer guide column 11A and the auxiliary column 12
Each column 11 is placed at a position opposite to the rail 1.
The fixing member 15 connected to A, 12 is the rail 1
The fixing member 15 and the outer side of the rail 1 are connected by a U-shaped fixing plate 16 to fix the rail 1 and the guide portion 8.

The shield body 6 is constructed by stacking a plurality of lead shield members 17 each having a mountain-shaped cross section. The shielding members 17 are stacked so that their corners are at the top as shown in FIG. 5a, and as shown in FIG. 5b.
When the shielding member 18 shown in FIG. 1 is a flat plate, it is possible to reliably prevent the streaming phenomenon in which radiation passes through the overlapped space. Note that the shielding members 17 may be stacked upside down as shown in FIG. 5c. In addition, this shielding member 17
is the manipulator 1 placed in the cell box 2.
For example, it is set to 4 kg or less in the operating load range of No. 9.

As shown in FIG. 6, the coil spring 13 that biases the shield receiving seat 7 upward is used to keep the upper end of the shielding member 17 stacked on the receiving seat 7 whenever the manipulator 19 stacks up and removes the shielding members 17. is the lower operating limit height h of the manipulator 19
The spring biasing force is set so as to be located above.
Therefore, the catch 7 on which the shielding member 17 is not placed is also located above the lower operating limit height h, as shown by the imaginary line, and since the shielding members 17 are stacked, the catch 7 is located above the lower limit height h of the shielding member 17. The lowermost end of the shield body 6 is lowered to maintain approximately the lower operating limit height h, and after the stacking is completed as shown by the solid line, the lowermost end of the shield body 6 is at the lower limit position lower than the lower operating limit height h, and the uppermost end is lower than the lower operating limit height h. can be assembled with a required predetermined height H higher than the lower operating limit height h, making it possible to shield a wide range.

The weight of each member of the radiation shielding device 5 is, for example, 4 times the gripping capacity of the manipulator 19.
Kg or less, and is designed so that all assembly and disassembly work can be performed by the manipulator 19.

This shielding device 5 is constructed by first transporting rail members such as rails and rail supports 4 from cell ports 3A and 3B of adjacent cell boxes 2A and 2B shown in FIG.
It is abbreviated as PVC bag. ) is assembled by a worker through the cell ports 3A and 3B, and is arranged between adjacent cell boxes 2A and 2B. Next, the member carried into one cell box 2B is moved on the transport plate 1a provided on the rail 1 and sent into the central cell box 2.

Next, the following operations are performed using the manipulator 19 to assemble the shielding device 5.

A pair of substrates 9 and this substrate 9 are aligned with the rail supports 4 opposing both sides of the cell port 3.
A shield support column 10, lower guide columns 11a, 11a, and auxiliary column 12 are arranged upright. (Fig. 7) A coil spring 13 is inserted into the shield support column 10, and these guide parts 8 and rails 1 are connected to the fixing plate 1.
Fix by 6. Furthermore, lower guide column 1
Upper guide columns 11b, 11b are connected to the upper ends of 1a, 11a via connecting portions 11c, 11c. (FIG. 8) The shield seat 7 is attached to the shield support column 10 and supported by a coil spring 13. Next, the backing plate 14 is attached to the shield receiving seat 7.

A predetermined number of shield members 17 are stacked on the shield receiver 7 from the opposite direction to the backing plate 14. (Figure 9).

Next, how to use this shielding device 5 will be explained.

In the assembled state as described above, after the rear door 20 of the cell box 2 is opened and a contamination check (smear check) and a dose rate check are performed using the pendant 21 (Fig. 10), the outer cell shield 22 is installed. and the cover body 23 of the cell port 3 is removed. (Figure 11) Secondary with neoprene work gloves
Connect the PVC back 24 to the PVC back attachment port of cell port 3 (hereinafter abbreviated as PVC port).
3a, and discard the primary PVC bag 25 that was attached to the PVC port 3a.

In order to open the cell shutter door 26 and remove the melting point product 28 from, for example, the experimental equipment 27 placed inside the cell of the radiation shielding device 5, a worker moves the special jig 29 to the outside of the cell port 3 or
Use the PVC bag 24 with gloves on to remove mounting bolts, etc. of the melting point parts 28, which cannot be done with the manipulator 19, and use this jig 2.
Leading of the 9th grade is performed by the manipulator 19. Next, the fitting with the in-cell crane 30 is attached to the melting point part 28. (FIGS. 12 to 14) During these operations, the radiation from the radiation source 28a of the melting point component 28 is shielded by the shield main body 6 as shown in FIGS. There will be no exposure to radiation. A is the shielding range of the shielding device 5.

After the transport container 32 sealed in the tertiary PVC bag 31 is inserted from the PVC port 3a, the shield member 17 is removed from above the shield seat 7 by the manipulator 19, and the melting point part 28 is transferred to the in-cell crane 30 and the manipulator. 19
The cells are transported into the transport container 32 and transported outside the cell box 2. (Fig. 15) Effects of the Invention As described above, according to the present invention, the shielding body is formed by stacking a plurality of shielding members each having a mountain-shaped cross section. It is also possible to prevent radiation streaming phenomenon caused by stacking shielding members. In addition, since the spring urges the shield receiver upward and positions the upper end at a substantially constant level depending on the number of shield members stacked on the receiver when stacking and removing shield members, the manipulator The shielding members can be stacked and removed within the operating range of the manipulator, and the shielding body can be placed below the operating range of the manipulator, making it possible to shield a wide range.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a radiation shielding device according to an embodiment of the present invention, FIG. 2 is a plan view thereof, FIG. 3 is a front view thereof, FIG. 4 is an overall plan sectional view including adjacent cells, and FIG. 5a, b, and c are explanatory views of the shielding member, FIG. 6 is a schematic explanatory view showing the manipulator operating range, and FIGS. 7 to 9 are plan views and side views illustrating the assembly of the shielding device, Front view, Figure 10~
15 is a working explanatory diagram of the shielding device in use, FIG. 10 is a plan sectional view thereof, FIGS. 11 and 12 are side sectional views thereof, FIG. 13 is a plan sectional view thereof, and FIG. 14 is a plan sectional view thereof. Figures 1 and 15 are side sectional views thereof. 2... Cell box, 3... Cell port, 3a
...PVC port, 5 ...Radiation shielding device, 6
...shielding body, 7... shielding seat, 8... guide section, 10... shielding support, 13... coil spring, 17... shielding member, 19... manipulator, A...... shielding range, h...Lower limit height for manipulator operation, H...Height of the shield body.

Claims (1)

[Claims] 1 A pair of shield supports are erected at a predetermined interval in positions facing the cell ports in the cell, shield supports that can be raised and lowered are provided on these shield supports, and springs are provided to bias the shield supports upward. was provided, and the biasing force of this spring was set so that the upper ends of the stacked shielding members were at a substantially constant level according to the number of shielding members having a mountain-shaped cross section stacked on the shielding seat. A radiation shielding device characterized by: