JPS60129696A - Radiation shielding structure of nuclear turbine facility - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a radiation shielding structure for nuclear turbine equipment.

[Technical background of the invention]

Generally, in the turbine equipment of a boiling water nuclear power plant, a high pressure turbine, a low pressure turbine, a generator, and a moisture separator are provided on the floor of the turbine building. The area around the moisture separator is shielded to prevent deterioration of the working environment due to radiation from the moisture separator.

FIG. 1 shows a conventional radiation shielding structure of this type.

In the figure, the symbol l is the reed on the turbine installation floor of the turbine building.
High-pressure turbine turbine, three low-pressure turbines 3 and generator ψ
are provided by connecting rotating shafts (not shown) in series,
There is. Further, moisture separators j are provided adjacent to both sides of the low pressure turbines 3.30 to remove moisture from steam extracted from the high pressure turbines and guide it to each low pressure turbine 3.13.

In order to shield this moisture separator j, a shielding wall B having a U-shaped cross section is provided between the ceiling of the turbine building (not shown) and the turbine installation floor l so as to surround the moisture separator j from the outside. , each shielding wall 6, between the open end faces of B, and between the low pressure turbine 3 and the high pressure turbine! A movable shielding wall 7.7 is provided between the generator 1 and the generator l.

In this way, conventionally, the shielding wall t and the movable shielding wall 7 separate the i-minute separators j, ! And surrounding the outer circumference of the low pressure turbine 3.3, the moisture separator! A region A with a high radioactivity level is divided into a region B parallel to the rotational axis of the turbine with a low radioactivity level.
and an axial end C.

[Problems with background technology]

The movable shielding wall 7 is a turbine! Since it is placed above the rotating shaft of the generator and generator, it is movable because it needs to be moved when the turbine is disassembled for periodic inspections, etc. It is made of steel plate and is supported from the turbine building. The structure is said to be

Because of this structure, it is not necessary to disassemble and reassemble the movable shielding wall 7 during periodic inspections.Furthermore, the movable shielding wall 7 is thick and heavy for the purpose of radiation shielding. Disassembly and reassembly work is a large undertaking, increases the number of man-hours required for periodic inspections, and forces an extension of the construction period.

Furthermore, since the radioactivity level is also high around the low pressure turbine 3, there is an inconvenience that the working environment for periodic inspection of the low pressure turbine 30 portion is poor.

Furthermore, there is also the disadvantage that a large-scale support structure is required to support the movable shielding wall 7, which is a heavy structure, from the turbine building.

[Purpose of the invention]

The present invention has been made in view of these points, and it eliminates the need to disassemble the shielding wall, which is a heavy structure, during periodic inspections of turbines, etc. (This invention can shorten the process and improve the working environment.) Another object of the present invention is to provide a radiation shielding structure for nuclear turbine equipment that is simple in structure and easy to manufacture.

[Summary of the invention]

The radiation shielding structure for the atomic cutter/equipment of the present invention is characterized in that only the moisture separator is surrounded entirely by a shielding wall that is a part of the turbine building.

(3) [Embodiments of the Invention] Examples of the present invention will be explained below with reference to Figures 2 to 6. Figure 2 shows the concept of the present invention, and the same parts as the figures A code is attached.

In the present invention, instead of the conventional movable shielding wall 7, the open end of a shielding wall B having a U-shaped cross section is hermetically closed by a shielding wall r, and only the moisture separator j is shielded.・As a result, only the area around the moisture separator j has a high radioactivity level, and the radioactivity level is kept low in the other parts B parallel to the turbine and the axial part C. .

3 and 1 show an embodiment of the present invention, in which the low pressure turbine 3 is installed on a turbine foundation,
Steam extracted from the high pressure turbine is supplied from the moisture separator j through each supply pipe 10 and IO. After this steam leaves the low pressure turbine 3, it is condensed by the condenser//.

And, between the turbine installation floor l and the ceiling l, there is a space (G'
) A shielding wall 6 having a U-shaped cross section and a shielding wall r formed to straddle each supply pipe 105IO are fixedly installed.

In this example, a moisture separator! is completely shielded by the turbine installation floor t, the shielding walls 6, t, and the ceiling 12. Since the shielding wall ♂ does not need to be disassembled, it can be a normal wall structure forming a turbine building, and the structure is simple.

FIGS. 5 and 6 show other embodiments in which the structure of the shielding wall is changed.

That is, the lower end of the shielding wall r ends above the supply pipe IO of the moisture separator j to form a hanging wall, and the steel plate shield 13 shown in FIG. 6 is detachably attached to the lower end of the shielding wall r. It is composed of This shield /3 has U-shaped portions /3a, /, ?, which serve as passages for the respective supply pipes 10.
a, and is shaped to seal between the shielding wall t and the outer circumferential surface of the turbine installation floor l and the low-pressure turbine y3.

In this way, in this embodiment, only the moisture separator j can be shielded by extending a part of the shielding wall B, which is a part of the framework structure of the turbine building, as a shielding wall r. . This makes it possible to limit the cavity radioactivity coverage area only to the area around the moisture separator j, eliminating the need for a shielding wall that is a heavy structure and can be moved and disassembled, which was required in the past, and also eliminates the need for its support structure. , a shielding structure with a simple structure can be formed. It is not necessary to disassemble the shielding wall even during periodic inspections of the turbine, which makes the work easier and reduces the number of steps and the work period. In addition, since the radioactivity around turbine generator 3 is kept low,
The working environment for turbine λ, 3-cycle pigeon roll work, etc. is improved.

〔Effect of the invention〕

Since the radiation shielding structure for nuclear turbine equipment of the present invention is constructed and operates in this way, there is no need to disassemble the shielding wall, which is a heavy structure, during periodic inspections of turbines, etc., and the process can be shortened. It has advantages such as a good working environment and a simple structure.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing a radiation shielding structure for a conventional nuclear turbine equipment, FIGS. 2 to 6 show an embodiment of the radiation shielding structure for a nuclear turbine equipment of the present invention, and FIG. 3 is a cross-sectional view of the low-pressure turbine section of one embodiment; FIG. V is a sectional view taken along the line IV-1V of FIG. 3; FIG. A cross-sectional view showing
Figure 5 is a perspective view of the shield. L...Turbine installation floor, K...High pressure turbine, 3.
...Low pressure turbine, Otsu, ♂...Shielding wall, tl...Ceiling. Applicant's agent Kiyoshi Inomata

Claims (1)

[Scope of Claims] Nuclear turbine equipment is provided with a moisture separator adjacent to the turbine on the turbine installation floor, and radiation shielding is provided by surrounding only the moisture separator with a shielding wall that is a part of the turbine building. A radiation shielding structure for nuclear power turbine equipment O2, characterized by A radiation shielding structure for nuclear turbine equipment according to claim 1, characterized in that the radiation shielding structure is sealed with a removably attached shielding body.