JPH06294895A - Radiation shield structure - Google Patents

Abstract

PURPOSE:To provide a shield structure for completely enclosing a radiation source, which is easy to assemble, dismantle, and modify. CONSTITUTION:Support columns 11, 12 are stood on a floor surface at specified intervals, connection materials 13, 14, 15 are connected between mutual upper end parts of their support columns 11, 12 and frames are constituted. Wall panels 16, 17 are mounted between the support columns of the frames. Celing panels 18 are mounted between the connection materials. Lead plates are incorporated on approximately al surfaces of the wall panels and the ceiling panels and the lead plates for covering gaps between the support column and the connection materials, between the fellows of the wall panels, and between the wall panel and the ceiling panel are included.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation shielding structure installed around a radiation source so as to surround it.

[0002]

2. Description of the Related Art In recent years, SOR light (synchrotron radiation light) emitted from a particle accelerator such as a synchrotron is taken out and used as a light source for various purposes such as VLSI manufacturing, diagnosis in the medical field, molecular analysis, and structural analysis. There is a momentum to use it in various fields, and facilities for it are being developed.

A particle accelerator for utilizing SOR light causes charged particles to orbit in an annular storage ring at a speed close to the speed of light, and takes out SOR light emitted from the charged particles in a tangential direction of a circular orbit through a beam line. It was done like this.

In such a particle accelerator, since harmful radiation (X-rays) is emitted from the storage ring, the entire storage ring is installed inside a thick concrete shielding wall. In addition, SOR is used for the beam line.
Various optical devices for light, such as a reflector and a spectroscope, are installed, but radiation is also emitted from these optical devices, and therefore the beam line together with the storage ring is inside the concrete shield wall. It is usually installed in.

[0005]

By the way, there is no particular problem if the beamline can be installed inside the concrete shield wall together with the storage ring as described above, but it is installed on the beamline due to various restrictions. Optical equipment may have to be placed outside the concrete shield. In such a case, another shielding structure for shielding the radiation emitted from the optical device must be installed. Then, in such a case, it is possible to form a relatively simple shielding wall by stacking lead blocks so as to surround the optical device or the beam line, thereby shielding the radiation from the optical device. It is common.

However, when the lead blocks are stacked to form the shielding wall, there is a concern that a slight gap is generated between the lead blocks and sufficient shielding performance cannot be obtained. Further, there is a problem that the work efficiency is not very good because it is difficult to mechanize the lead block stacking work and the dismantling work.

The above is a problem that occurs not only in the beam line of the particle accelerator but also in the case where a relatively simple shielding structure is installed around the radiation source in various radiation facilities. Effective improvement measures were requested.

The present invention has been made in view of the above circumstances, and is an effective shielding structure that not only can effectively shield radiation, but can also be easily assembled and disassembled or remodeled as necessary. Intended to provide the body.

[0009]

DISCLOSURE OF THE INVENTION The present invention is a radiation shielding structure which is installed around a radiation source so as to surround it, and in which pillars are erected on the floor surface at predetermined intervals. A frame is formed by connecting the upper ends of the adjacent columns with a connecting material, and a wall panel is attached between the columns of the frame, and a ceiling panel is attached between the connecting materials to the wall panel and the ceiling panel. Each of them has a radiation shieldable lead plate installed over almost the entire surface thereof, while the pillar has a lead plate that can close the gap between the wall panels, and the connection member has a space between the ceiling panels. Also, a lead plate capable of closing the gap between the wall panel and the ceiling panel is incorporated.

[0010]

The shield structure of the present invention is constructed by using members that are manufactured in advance according to a predetermined standard and assembling them. That is, columns are installed at predetermined intervals, the upper ends of the columns are connected by a connecting material to form a frame, wall panels are built between the columns to form a wall surface, and the ceiling panel is supported by the connecting material. By doing so, the ceiling surface is formed. Lead plates for shielding radiation from almost all surfaces of wall panels and ceiling panels are incorporated, and lead plates are also incorporated in columns and connecting materials, and each member is assembled in a state where the lead plates are stacked on top of each other. As a result, the radiation is shielded without any gap.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. The shielding structure of the present embodiment is applied to the beam line of a large particle accelerator as shown in FIG.
In FIG. 1, reference numeral 1 is a storage ring, 2 is its shielding wall, 3 is a beam line, and 4 is a shielding structure of this embodiment.

The storage ring 1 is a large-scale one having a diameter of, for example, several hundred meters and a perimeter of 1,000 meters or more. Inside the storage ring 1, charged particles such as electron beams circulate at a speed close to the speed of light. Has become. The shield wall 2 is made of reinforced concrete with a thickness of about 1 meter, and is installed so as to surround the storage ring 1 so as to shield the radiation emitted from the storage ring 1. The beam line 3 is for extracting the SOR light emitted by the charged particles circulating in the storage ring 1 to the outside. The beam line 3 extends from the storage ring 1 in the tangential direction thereof, penetrates the shielding wall 2 and is guided to the outside. ing.

The beam line 3 is provided with an optical device 5 such as a reflecting mirror and a spectroscope located outside the shielding wall 2, and in this embodiment, the radiation emitted by them is shielded. The shielding structure 4 is provided so as to be continuous with the shielding wall 2. The beam line 3 penetrates the front wall surface of the shielding structure 4 and extends further to the front, and a device or facility (not shown) for utilizing SOR light is installed on the tip side thereof.

The shielding structure 4 of the present embodiment uses the following members which are manufactured in advance based on a predetermined standard, and they are shown in FIG.
~ It is constructed by assembling as shown in Fig. 5. That is, in the shielding structure 4 of the present embodiment, the side pillars 11 and the front pillars 12 are erected on the floor surface at predetermined intervals, and the side pillars 11 and the front pillars 12 are provided.
Between the upper end portions of the horizontal connecting members 13 and 14 and the vertical connecting member 1
5, a frame is formed by connecting vertically and horizontally, and a side wall panel 16, a front wall panel 17, and a ceiling panel 1 are attached to the frame.
It is constructed by attaching 8 respectively.

The dimensions of the shielding structure 4 may be set appropriately. In this embodiment, the overall width W shown in FIG. 1 is about 2 meters, the length L is about 10 meters, and the height is about 10 meters. The size is about 2.5 meters, and the side support 11
The installation interval is about 1 meter. In this case, the side wall panel 16 and the front wall panel 17 are each about 1 meter wide and about 2.5 meters high, and the ceiling panel 18 is about 1 meter wide and about 2 meters long. In addition, the height of the side support 11 and the front support 12 is about 2.5 meters, the length of the horizontal connecting members 13 and 14 is about 2 meters, and the vertical connecting member 15
Is about 1 meter long. Further, the side wall panel 16
The thickness of the front wall panel 17 is preferably about 20 mm, and the thickness of the ceiling panel 18 is preferably about 30 mm.

Each of the above-mentioned members is mainly formed of a metal material such as stainless steel, and a lead plate for shielding radiation is incorporated in each of them, and each of them is formed. By overlapping the lead plates of the members with each other and assembling the members so that no gap is formed between them, the shielding structure 4 can completely shield the radiation without gaps.

Each member will be described below.
First, a side wall panel 16 for forming both side wall surfaces of the shielding structure 4, and a front wall panel 1 for forming a front wall surface.
7. The ceiling panel 18 for forming the ceiling surface is formed in a rectangular flat plate shape as shown in FIG. 2, although the ceiling panel 18 has different outer dimensions and thicknesses. Side wall panel 16
For example, the cross-sectional shape of the lead plate 2 is as shown in FIG.
The stainless steel plate 22 is attached to the outer periphery of the No. 1 in a form of covering it and welded. in this case,
It is preferable that the lead plate 21 has a thickness of about 10 mm and the stainless plate 22 has a thickness of about 5 mm to 10 mm. Further, a large number of pins 23 for attaching a heat insulating material (not shown) are attached to these inner surfaces at predetermined intervals. Further, as shown in FIG. 2, each of these panels 16, 17 and 18 is formed with a screw hole 24 for attaching an eye bolt (not shown) used when hoisting them by a crane.

The front wall panel 17 for forming the front wall surface of the shielding structure 4 is divided into two because of the beam line 3 penetrating therethrough as shown in FIG. The front wall panel 17 is formed with semicircular cutouts 25 at the penetrating positions of the beam lines 3. The gap between the abutting surfaces of the two front wall panels 17 is closed by the two closing plates 31. As shown in FIG. 3, the closing plate 31 includes a lead plate 32 and a stainless plate 3 as in the above panels 16, 17, and 18.
It is formed by being covered with 3 and is attached so as to straddle both front wall panels 17 and 17 by the angle member 34 previously attached to both front wall panels 17 to thereby form a gap between them. The blockage prevents radiation from leaking from this part.

Next, the side pillars 11 for supporting the side wall panel 16 are, as shown in FIG.
It has a bracket 42 attached to its upper portion and a base 43 attached to its lower portion. The body portion 41 is formed by covering a lead plate 44 having a thickness of 10 mm with a stainless steel plate 45 having a thickness of 5 mm, and the body portion 4
Grooves 46 into which the side edge portions of the side wall panels 16 are fitted are formed on both sides of 1 from the upper end to the lower end over the entire length. The brackets 42 are used to fasten the end portions of the one horizontal connecting member 13 and the two vertical connecting members 15, respectively, and are provided in the front and rear direction and the width direction inner side of the shielding structure 4 to be constructed. Bolt holes 47 are formed to face the direction and fasten the horizontal connecting members 13 and the vertical connecting members 15. The bracket 42 is provided at a position slightly lower than the upper end of the column 11, the horizontal connecting member 13 and the vertical connecting member 15 are fastened to the bracket 42, and when the ceiling panel 18 is placed thereon, the ceiling Panel 1
8 and the upper end surface of the pillar 11 are substantially aligned with each other, so that the four corners of the ceiling panel 18 have four pillars 11 each.
It engages with the upper end of the and is prevented from being displaced or dropped. Also, the base 43 is the support 1
It is for fixing 1 to the floor surface with anchor bolts to make it self-supporting.

The struts 11 thus formed are used by being erected on the floor surface at a predetermined interval (in this embodiment, about 1 meter interval as described above) corresponding to the width dimension of the side wall panel 16. To be Then, as shown in FIG. 3, the side wall panel 16 is inserted between the adjacent columns 11 by inserting the side edge portions of the side wall panels 16 into the groove portions 46 of the columns 11.
The side wall panel 16 can be installed on these columns 1
The side wall surface of the shielding structure 4 is formed by being supported by the first and the first structures. In this case, as shown in FIG.
The lead plate 44 incorporated in 1 overlaps with the respective lead plates 21 incorporated in both side wall panels 16 supported by the column 11 in a side view, and therefore, the lead plates 21, 44 are , 21 prevent radiation from leaking at this portion.

Further, the front support column 12 has the shielding structure 4
The front wall panel 17 and the side wall panel 16 are supported in a state of being orthogonal to each other by being used at the foremost part of the main body 51 and the bracket 52, as shown in FIG. , Base 53. Body 51
The groove portions 54, 54 into which the front wall panel 17 and the side wall panel 16 are fitted are formed so as to be orthogonal to each other.
Lead plate 55 having an angled cross-sectional shape so as to close the gap between the front wall panel 17 and the side wall panel 16.
Is covered and incorporated in the stainless plate 56. Further, one horizontal connecting member 1 is provided at the upper end of the front support column 12.
Since the 4 and the vertical connecting member 15 are connected in an orthogonal state, the bracket 52 is provided in two directions of the rear side and the width direction inner side. In addition, at the upper end portion of the front support column 12, a part of the lead plate 55 is cut off as shown in FIG. 8 in order to connect the horizontal connecting members 14.

Further, although the horizontal connecting members 13 and 14 and the vertical connecting member 15 have different width dimensions and length dimensions, in each case, the lead plate 61 is covered with the stainless plate 62 as shown in FIGS. 9 and 10. It has a formed rectangular cross section, and bolt holes 63 for fastening to the brackets 42 and 52 of the side support 11 and the front support 12 are formed at both ends thereof. These horizontal connecting materials 1
As shown in FIG. 4, the vertical connecting members 3 and 14 connect the upper ends of the side pillars 11 and the front pillars 12 to each other to form a frame serving as a skeleton of the shielding structure 4. It is a thing. Then, as shown in FIG. 5, the outer peripheral edge portion of the ceiling panel 18 is supported by the horizontal connecting members 13 and 14 and the vertical connecting member 15, and the ceiling panel 1
The ceiling surface of the shielding structure 4 is constituted by 8.

In this case, the horizontal connecting member 13 has two ends on both sides thereof.
The outer peripheral portions of the two ceiling panels 18, 18 are to be placed, and therefore the two ceiling panels 18, 18 are placed.
Since the outer peripheral edge portion of and the horizontal connecting member 13 are overlapped with each other in a plan view, the gap formed between the two ceiling panels 18, 18 is closed by the horizontal connecting member 13, and the radiation of this portion is blocked. Leakage is prevented. Also, the vertical connecting member 15
Supports the end portion of the ceiling panel 18 in the longitudinal direction and closes the gap between the ceiling panel 18 and the side wall panel 16, so that the radiation of radiation in this portion is prevented by the vertical connecting member 13. It has become. Further, the horizontal connecting member 14 connecting the two front support columns 12 and 12 supports only the frontmost ceiling panel 18, and the width dimension thereof is about half that of the other horizontal connecting members 13. The horizontal connecting member 14 closes the gap between the ceiling panel 18 and the front wall panel 17 to prevent the leakage of radiation in this portion.

As described above, in the above-mentioned shield structure 4, the columns 11 and 12 are erected on the floor, and the upper end portions thereof are vertically and horizontally connected by the horizontal connecting members 13 and 14 and the vertical connecting member 15. Is constructed by attaching a side wall panel 16, a front wall panel 17, and a ceiling panel 18 to the frame, and the assembling work can be easily performed by using a simple crane. Further, it is easy to dismantle the shielding structure 4 constructed in this way and to remodel it as necessary.

Then, in the above-mentioned shield structure 4,
Lead plate 2 over almost the entire surface of each panel 16, 17, 18
1 is installed, so those panels 16, 17,
Even if 18 is relatively thin, it can effectively shield radiation, and each panel 16, 17,
A gap that is inevitably formed between 18 is inevitable. The closing plate 31, the columns 11, 12, the connecting members 13, 1
Lead plates 32, 44, which are respectively incorporated in 4, 15,
It is completely covered by 55 and 61 without any gap, and therefore, excellent shielding performance can be ensured in which radiation does not leak from anywhere.

When a door is provided in the shielding structure of the above embodiment, one of the side wall panels 16 is connected to the side support 11 by a hinge 71 so as to be openable and closable as shown in FIG. By processing the groove portions 46 of the two side pillars 11 on both sides so that the side wall panel 16 can be opened and closed, the side wall panel 16 is left as it is.
Can be used as

When ventilation or cooling of the inside of the shielding structure 4 is performed, a device 81 such as a ventilation fan or an air conditioner is attached to one of the side wall panels as shown in FIGS. 12 and 13. The side wall panel 82 for that purpose may be prepared in advance. In this case, an opening 83 for attaching the devices 81 is formed in the side wall panel 82. However, since radiation leaks to the outside through the opening 83 as it is, the air flow as shown in FIG. A partition plate 84 is provided inside the opening 83 in such a form that it can bypass and circulate, but can block radiation. Of course, the side wall panel 82 and the partition plate 84
In the same manner as the general side wall panel 16, a lead plate is covered with a stainless plate.

Further, in addition to installing the shielding structure 4 around the beam line 3 as described above, as shown by a chain line in FIG. It is more preferable to separately install another shielding structure 91 that directly surrounds and to doubly shield with both shielding structures 4 and 91. In this case, even as the inner shielding structure 91 that directly shields the optical device 5, it is possible to adopt the basically same structure as the shielding structure 4 of the above embodiment only by reducing the size of each part. Of course.

[0029]

As described above, the shield structure of the present invention is constructed by assembling standardized members such as columns, connecting members, wall panels and ceiling panels. Therefore, compared to the conventional case of stacking lead blocks, it is of course possible to install, dismantle, or remodel this shielding structure more easily. Since the lead plates for closing the gaps between the panels are also incorporated in each of the columns and the connecting members, there is no gap anywhere, and the excellent shielding performance can be secured.

[Brief description of drawings]

FIG. 1 is a plan view showing a state in which a shield structure according to an embodiment of the present invention is installed on a beam line of a large particle accelerator.

FIG. 2 is an exploded perspective view showing an assembled state of the shielding structure.

FIG. 3 is a partial plan sectional view showing an assembled state of the shielding structure.

FIG. 4 is a partial plan view showing an assembled state of the shielding structure.

FIG. 5 is a partial plan view showing an assembled state of the shielding structure.

FIG. 6 is a perspective view showing a wall panel in the shielding structure.

FIG. 7 is a perspective view showing a side strut of the shielding structure.

FIG. 8 is a perspective view showing a front support column of the shielding structure.

FIG. 9 is a perspective view showing a lateral connecting member in the shielding structure.

FIG. 10 is a perspective view showing a vertical connecting member in the same shielding structure.

FIG. 11 is a partial plan cross-sectional view showing an example of a case where a door is provided in the same shielding structure.

FIG. 12 is a partial plan cross-sectional view showing an example in which a device for ventilation or cooling is installed in the shielding structure.

FIG. 13 is a side sectional view of the same.

[Explanation of symbols]

 4 Shielding Structure 5 Optical Equipment (Radiation Source) 11 Side Support (Support) 12 Front Support (Support) 13, 14 Horizontal Connecting Material (Connecting Material) 15 Vertical Connecting Material (Connecting Material) 16 Side Wall Panel (Wall Panel) ) 17 front wall panel (wall panel) 18 ceiling panel 21,44,55,61 lead plate 91 shielding structure.

Claims (1)

[Claims] 1. A radiation shielding structure which is installed around a radiation source so as to surround the radiation source, wherein columns are erected at a predetermined interval on a floor surface, and the columns are arranged between upper ends of adjacent columns. A lead plate capable of radiation shielding is attached to each of the wall panel and the ceiling panel, and a wall panel is attached between the columns of the frame, and a ceiling panel is attached between the connection members. , And lead plates that can close the gaps between the wall panels are incorporated in the columns, and the connecting members are provided between the ceiling panels and between the wall panels and the ceiling panels. A radiation shielding structure, characterized in that a lead plate capable of closing a gap therebetween is incorporated.