JPH11295482A - Expansion and contraction type simple radiation shield vessel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple radiation shield vessel which has high exposure reduction effect of workers, and in which a shield working amount is lessened under high radiation in the case where shield of radiation is required quickly and emergently in a facility having a radiation source. SOLUTION: The inside of a shield vessel 1 is provided with a waterproof expansion and contraction material-made inside vessel 5, and the formed shield vessel 1 is fully filled by extending the shield vessel 1 up to necessary size, and after size securing, by injecting shield material 2 from the water injection opening 3 of the upper part to the inside vessel 5. As a result, the empty shield vessel is set under high radiation, since the shield vessel is lightweight, setting is completed in a short period, a shield working amount is lessened under high radiation, and effect for reducing the workers, exposure exists.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to equipment for shielding radiation from equipment having a radiation source.

[0002]

2. Description of the Related Art In general, a facility for installing equipment having a radiation source uses a lead or concrete to construct a shielding wall having a necessary shielding thickness for preventing exposure. A radiation shielding device described in JP-A-5-142392 (prior art 1) as a shielding device is obtained by filling a hollow metal casing with a boron-containing fluid and a metal oxide mixed therein. Solidified state, Na ₂ B ₄
O _7, B ₂ O ₃ and Bpo, are used Fe ₂ O ₃ or the like, mainly shield the neutron beam by boron and hydrogen, and is intended to shield the gamma rays by the casing and the metal.

[0003]

In the prior art 1 described above,
This method shields gamma rays with a metal shielding container and neutrons with a shielding material (boron-containing material) contained in the container. However, it is considered effective at the time of initial planning of equipment, but since the container is metallic, weight is high. The shielding effect is high because boron-containing materials are used for the shielding material, but the shielding material must be sealed in a container in advance, and emergency measures such as securing a storage space for the shielding material and carrying in and out work are required. The workability at the time of rebuilding the target quickly and quickly is not good.

[0004] An object of the present invention is to reduce the amount of shielding work under high radiation when it is necessary to quickly and urgently shield radiation in equipment having a radiation source.
An object of the present invention is to provide a simple radiation shielding container having a high effect of reducing exposure of workers.

[0005]

In order to achieve the above object, the shielding container of the present invention is stretched to a required size, and a shielding material is poured into an inner container made of a waterproof stretchable material from a water inlet at an upper portion. This is achieved by ending the working time for filling the internal container in a short time.

That is, in claim 1, an inner container made of a waterproof and stretchable material is installed inside the container, the outer container has a structure in which the side surface folds up and down, the upper surface of the outer container has a convex shape, and the lower surface of the outer container has a lower surface. It has a concave shape, and a water inlet for filling the inner container with a shielding material (fluid substance) is provided on the upper surface. After extending the outer container until the required shielding dimensions are secured, the shielding material is inserted through the water inlet. Filling the container allows the extended shielding container to be filled.

According to the second aspect of the present invention, the material of the shielding container is made of a light-weight flammable substance, which enables incineration and disposal after use, thereby reducing the amount of radioactive waste.

[0008] In the third aspect, the shielding material to be filled in the shielding container is water.

[0009]

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

FIGS. 1A and 1B show an embodiment in which a telescopic simple radiation shielding container is extended.

At the upper part of the telescopic simple radiation shielding container 1, a water inlet 3 for filling the shielding material 2 (fluid substance) in the convex portion is provided on the upper part of the container 1, and a drain port 4 is provided at the lower part of the side surface of the container 1. The shielding container 1 is provided with an inner container 5 made of a preventive expandable material connected to the upper and lower inlet and outlet ports 3 and 4 of the shielding container 1 so that the side surface of the shielding container 1 folds and expands. By having this, the shielding container 1 is stretched to a required shielding size, and after securing the dimensions, the shielding material 2 is filled into the inner container 5 from the upper water inlet 3 to fill the formed shielding container 1.

For example, in the case of a nuclear power plant, if the shielding container 1 needs to enter an area where radionuclides are a radiation source or a high radiation dose area for some reason during operation of the power plant, It is used as temporary shielding equipment near the radiation source to reduce the exposure dose to workers who are standing. Since the installation place is generally under a high dose rate condition, it is first necessary that the work be performed in a short time in order to minimize the exposure dose when installing the shielding container 1.

The dimensions of the shielding container 1 are, for example, the shielding material 2
When water is used, in order to reduce the dose rate reduction effect of the shielding material 1 to 1/10 with respect to the case where there is no shielding material, as shown in FIG. 2, for Co-60γ ray (1.25 MeV), A thickness of about 70 cm is required. Therefore, the dimensions of the shielding container 1 are as follows: thickness a 70 cm, width b 100 cm.
Is appropriate.

The material of the shielding container 1 may not be made of metal as long as the shielding container 1 is stretched to a required shielding dimension and a sufficient strength is maintained when the shielding material 2 is injected into the inner container 5. Considering the ease of carrying in and out and disposal treatment after removal, flammable substances such as reinforced plastics are used, and the weight is reduced.

In the installation, only the empty empty shielding container 1 is loaded and installed, and a hose for injecting the shielding material 2 from the low dose rate area to the empty shielding container 1 is connected to perform the injection operation. Exposure due to installation is also only when the empty shielding container 1 is carried in, and is effective in reducing the exposure dose.

After the shielding material 2 is discharged by its own weight by opening the lower pouring and draining port 4 of the shielding container 1 during a predetermined period of power generation inspection in which high radiation in the area where the shielding container 1 is installed is eliminated. Then, the extended shielding container 1 is contracted. Since it is lighter than a conventional shielding material, for example, lead, the workability of carrying out the shielding container 1 is improved. FIG. 3 shows the storage state of the telescopic simple radiation shielding container.

[0017]

According to the telescopic simple radiation shielding container of the present invention, the equipment for shielding radiation from equipment having a radiation source can be operated under high radiation only by installing an empty shielding container. Is lighter, the installation is completed in a short period of time, there is an effect that the amount of shielding work under high radiation is reduced, and the amount of exposure of workers is reduced. Further, by using a flammable substance in the shielding container, the disposal property after use is improved.

[Brief description of the drawings]

FIGS. 1 (a) and 1 (b) are a perspective view showing a shielding container according to an embodiment of the present invention and a sectional view taken along line AA of FIG. 1 (a).

FIG. 2 is a characteristic diagram showing an attenuation rate in a water shield for a point source.

FIG. 3 is a sectional view showing a storage state of FIG. 1;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Shielding container, 2 ... Shielding material, 3 ... Water inlet, 4 ... Drainage outlet, 5 ... Inner container made of waterproof elastic material.

Claims (3)

[Claims] The present invention relates to a facility for shielding radiation from a facility having a radiation source, wherein an inner container made of a waterproof stretchable material is installed inside the container, the outer side surface of the container folds and expands, and the upper surface of the container is convex. Shape, the lower surface of the container is concave, the upper surface is provided with a water inlet for filling a shielding material (fluid substance), and the lower side of the container is provided with a water inlet for discharging, until the container has the required shielding dimensions. After extending, from the water inlet,
A telescopic simple radiation shielding container that can fill a stretched shielding container by injecting shielding material. 2. A telescopic simple radiation shielding container according to claim 1, wherein said shielding container is made of a flammable substance. 3. The telescopic simple radiation shielding container according to claim 1, wherein water is used as a shielding material to be filled in the shielding container.