JPS63118458A - Scaffold apparatus for pressure control chamber of nuclear reactor - Google Patents

Abstract

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

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to a scaffolding device for a pressure suppression chamber of a nuclear reactor, and more specifically, it is used when carrying out construction work in a pressure suppression chamber surrounded by a torus shell. Relating to scaffolding equipment.

``Prior Art'' There is a pressure suppression chamber in a boiling water reactor having a structure shown in FIG. Is this pressure suppression chamber 2 the reactor containment capacity? 541 is formed in a torus shell 1 connected via a plurality of vent pipes 3, pool water W is stored inside, and steam is spouted out in the event of an accident inside the reactor containment vessel 41. In this case, the steam is guided into the pool water W via the vent pipe 3 and condensed, thereby suppressing the pressure increase in the reactor containment vessel 41. Further, in this pressure suppression chamber 2, construction works such as removal of deposits adhering to the inner bottom surface, painting of the inner surface, remodeling, etc., may be performed.

Conventionally, scaffolding devices used when carrying out construction work inside the pressure suppression chamber 2 have been constructed by placing a scaffolding frame assembled from steel pipes or the like on the inner bottom of the torus shell 1, and then moving around the pressure suppression chamber 2. A plurality of scaffolding frames are arranged at mutual intervals in the direction, and scaffolding boards are laid between each scaffolding frame.

"Problems to be Solved by the Invention" However, with such a scaffolding device, skill is required to assemble the scaffolding frame on the circular arc surface at the inner bottom of the torus shell l, and it is difficult to assemble the scaffolding device. Even if construction is carried out on top of that, the torus shell l
There is a portion where the scaffolding device is placed on the inner bottom where it is virtually impossible to carry out construction work. Therefore, pressure suppression chamber 2
After carrying out most of the construction work and removing the scaffolding device from the pressure suppression chamber 2, it is necessary to repair the area left by the scaffolding device. In this case, the inner bottom part of the torus shell l is a part that is buried by the pool water W as shown in FIG. 8, and it is not preferable that a part be re-repaired in a separate process.

The present invention effectively solves the above-mentioned problems, and aims to provide a scaffolding device that facilitates assembly in a pressure suppression chamber and enables high-quality work to be carried out, particularly in the pool hydraulic joint. .

"Means for Solving the Problems" The present invention has a scaffold frame body in which a plurality of scaffold frames are arranged at mutual intervals in the circumferential direction of a pressure suppression chamber and scaffold boards are placed between them, and the scaffold The frame body is formed into a gate shape with vertical frames arranged at both ends of the horizontal frame, and the horizontal frame has a clamp fixed to the rail on the upper wall of the torus shell and a mounting section placed on the vent header. and the vertical frame has a length that separates it from the inner bottom surface of the torus shell when it is suspended from the horizontal frame placed on the vent header. This is a characteristic feature.

"Operation" The scaffolding device of the present invention fixes the clamp to the rail with the mounting part of the horizontal frame in the scaffolding frame placed on the vent header, so that part of the strength is borne by the rigid bent header. At the same time, a vertical frame is suspended from both ends of the horizontal frame. Then, a plurality of scaffold frames fixed in this manner are arranged at mutual intervals in the circumferential direction of the pressure suppression chamber, and a scaffold board is disposed between the frames, thereby assembling the pressure suppression chamber.

In addition, in this assembled state, the lower end of the vertical frame is separated from the inner bottom surface of the torus shell,
Therefore, there is no need for local re-repair on the lower inner surface of the torus shell, which becomes a part submerged in pool water.

"Embodiment" Hereinafter, one embodiment of the scaffolding device for a pressure suppression chamber of a nuclear reactor according to the present invention will be described based on FIGS. 1 to 7.

In FIGS. 1 and 2, reference numeral 1 indicates a torus shell in which a pressure suppression chamber 2 is formed, and 3 indicates a plurality of vents provided in a state where the reactor containment vessel (the path shown) and the torus shell 1 are connected. A vent header 4 is provided along the circumferential direction of the pressure suppression chamber 2 with the tips of the vent pipes 3 connected to each other, and a plurality of vent headers 5 are provided at intervals in the circumferential direction of the vent header 4. If the tip is wet with pool water (
A downcomer (6) is buried in the pressure suppression chamber 2 and is suspended from the upper wall of the torus shell l.
The vent header 4 and the rail 6 are spaced apart from each other in the horizontal direction, and the vent header 4 is A plurality of supports (paths shown in the figure) are provided between the torus shell l and the torus shell l has a rigid structure.

Reference numeral 7 indicates a scaffolding device according to the present invention.

This scaffolding device 7 is connected to the vent header 4 as described later.
It is composed of a plurality of scaffolding frames 8 arranged at mutual intervals in the circumferential direction of the pressure suppression chamber 2 while being supported by a rail 6 and a scaffolding plate 9 extending between each scaffolding frame 8. There is.

The scaffold frame 8 is assembled from steel pipes, etc., and as shown in FIG. 1, it is composed of a horizontal frame 10 and vertical frames 11 arranged at both ends thereof, and has a portal shape as a whole. It is something that exists.

The horizontal frame 1O has two rods 1 made by connecting steel pipes.
2A-12B are integrally connected in parallel to each other by a connecting pipe 13, etc., and these rods 12A-12B are used in a vertically lined state as shown in FIG. , a clamp 14 that is locked to the rail 6 is provided. As shown in FIGS. 3 and 4, this clamp 14 includes both rods 12A-12B.
A mounting pipe 15 is slidably inserted into the upper rod 12A of the mounting pipe 15, and a connecting piece 1 is attached to a support piece 16 integral with the upper side of the mounting pipe 15 via a hinge 17 so as to be vertically rotatable.
8 is provided, a support plate 19 is engaged with the connecting piece 18, and a pair of angled holding members 20 for fixing the rail 6 are removably attached to the support plate 19 with bolts 21. It is said that the configuration is as follows. That is, the stop plate 22 is fixed to the connecting piece 18 in a perpendicular state, and the supporting plate 19 is provided with a hole 23 into which the connecting piece 18 is inserted. By connecting the end portion to the support piece 16 with a bolt, the hinge 17 that rotatably supports the connection piece 18 is formed, and the support plate 19 is prevented from being removed by the stop plate 23. It looks like this. The presser members 2o are attached to the upper surface of the support plate 19 so as to face each other through the holes 23, and a plurality of claws 24 protruding from the opposing surface of the presser members 2o are attached to the upper surface of the support plate 19. The lower end of the rail 6 is held between the stop plate 23 and the stop plate 23, as shown by the chain line in FIG.

On the other hand, a mounting portion 25 that is placed on the upper surface of the vent header 4 is formed in the center portion of the horizontal frame IO in the length direction. As shown in FIGS. 5 and 6, the mounting section 25 includes a vertical plate 26 that extends downwardly from the lower side of the lower rod 12B, and supports both sides of the vertical plate 26 so that it can swing. A reinforcing plate 27 that serves as a stop is integrally fixed to the vertical plate 26, and a backing plate 28, which is curved to a slightly larger curvature than the outer diameter of the vent header 4, is placed at the lower end of the vertical plate 26, with its concave surface facing downward. It has a fixed configuration.

Note that the horizontal frame 10 having such a configuration has torus shells at both ends when the mounting portion 25 is placed on the upper surface of the vent header 4! It is formed in a length that is spaced apart from the inner surface.

Two hanging tools 29 are attached to both ends of the lower rod 12B of the horizontal frame IO so as to be movable in the length direction, and the vertical frame 11 is connected to the hanging tools 29 in a suspended state. There is.

The vertical frame 11 consists of two rods 30 made by connecting steel pipes.
A and 30B are fixed in parallel to each other by a connecting member 31, and the upper end of each rod 30A and 30B is attached to the hanging tool 29 of the horizontal frame IO with a bolt 32, as shown in FIG.
As shown in FIG.
It is formed to be smaller than the distance between it and the inner bottom surface. In addition, the outer rod 30A of this vertical frame 11 has
A plurality of clamp fittings 3 are spaced apart from each other in the length direction.
3 is attached, and an auxiliary arm 34 is pin-coupled to each clamp fitting 33 so as to be vertically rotatable. Each of these auxiliary arms 34 has its distal end and outer rod 30
A is held in a horizontal state by a chain 35 that connects the torus shell 1, and in the horizontal state, the tip is formed in such a length that it is separated from the inner surface of the torus shell 1, and the tip has a A handrail 36 is provided.

As shown in FIG. 1, both vertical frames 11 are disposed outside the downcomer 5, and in FIGS. 1 and 2, reference numeral 37 indicates a scaffolding frame. 8 and between both vertical frames 1 in each scaffolding frame 8, and fixes them as one body.

When assembling the scaffold device 7 configured in this manner in the pressure suppression chamber 2, the scaffold frame 8 is suitably divided and transported into the pressure suppression chamber 2, and the mounting portion 25 of the horizontal frame 10 is first vented. While placed on the top surface of the header 4, the clamp 14 at the end thereof is attached to the rail 6. In this case, by sliding the mounting pipe 15 of the clamp 14, the mounting portion 25 and the clamp 14 are connected to the vent header 4 and the rail 6.
Horizontal alignment can be performed with Next, each rod 3 of the vertical frame 11 is attached to the hanging tool 29 of the horizontal frame 10.
The auxiliary arm 34 is held horizontally by suspending the rods 0A and 30B.In this case as well, by moving the hanging tool 29 appropriately, the hanging tool 29 and each rod 30A and 30B are held horizontally.
It is possible to perform alignment with 0B and adjustment of hanging positions of the rods 30A and 30B relative to the downcomer 5 and the like.

Further, in the vicinity of the installation position of the clamp 14, the clamp 14 and the hanging tool 29 may overlap in the vertical direction;
Since they are separately provided on both rods J2A and 12B of 0, mutual interference between them can be prevented.

While assembling the scaffolding frames 8 in this way, a plurality of scaffolding frames 8 are arranged at mutual intervals in the circumferential direction of the pressure suppression chamber 2, and the scaffolding frames 8 are arranged between each other and between both vertical frames 10 of each scaffolding frame 8. The connecting rod 37 is stretched across and fixed integrally to connect the horizontal frame lO1 connecting member 31 and the auxiliary arm 3.
By laying scaffolding boards 9 between the four etc., the scaffolding device 7
is configured.

In the assembled state, the scaffold frame 8 is placed on the vent header 4 which is arranged in a rigid structure in the pressure suppression chamber 2, and some of the strength is imparted to the vent header 4. In addition, by being supported by the vent header 4 and the rail 6 at three locations spaced apart in the horizontal direction, vibration in the rotational direction about the mounting portion 25 is prevented. In addition, as shown in FIG. 1, both ends of the horizontal frame 10, the tips of each auxiliary arm 34, and the lower end of the vertical frame 11 are spaced apart from the inner surface of the torus shell l, so that they are disposed on the scaffold frame 8. Work such as painting can be uniformly performed on the entire inner surface of the torus shell 1 from the scaffold board 9 provided, and there is no need for local repair of the inner surface of the torus shell 1. In this case, the rail 6 and the upper surface of the vent header 4, on which the scaffolding frame 8 is supported, will need to be locally repaired, but these parts will not be submerged in the pool water as shown in Figure 8. Yes, there is little impact from re-repair. In other words, by using this scaffolding device 7, high-quality work can be carried out, especially in the pool hydraulics and parts.

Note that the detailed structure of each component in the scaffolding device of the present invention is not limited to the one embodiment described above, and the design can be changed as appropriate.

"Effects of the Invention" As explained above, according to the scaffolding device for a pressure suppression chamber of a nuclear reactor according to the present invention, the following effects can be achieved.

(1) Since the clamp is fixed to the rail with the mounting part of the horizontal frame placed on the vent header of the pressure suppression chamber, part of the overall strength is borne by the rigid vent header, and By supporting the vent header and the rail at three points spaced apart in the horizontal direction, swinging around the mounting part can be prevented, and a strong scaffold can be constructed.

(11) Since the vertical frame suspended from the horizontal frame is spaced apart from the inner bottom surface of the torus shell, work such as painting can be uniformly applied to the entire inner surface of the torus shell, making it especially possible for pool hydraulics. This allows the department to carry out high-quality construction work.

(iii) Since the vertical frame is suspended from both ends of the horizontal frame supported by the vent header and the rail, the assembly work is easier than with conventional scaffolding devices that are assembled on the arcuate surface of the torus shell. It can be easily done.

[Brief explanation of the drawing]

FIG. 1 is a front view showing a state in which a scaffolding device according to an embodiment of the present invention is arranged in a pressure suppression chamber, and FIG. 2 is a plan view showing a state in which a scaffolding frame is arranged in the scaffolding device of FIG. Fig. 3 is an enlarged view of the part indicated by the chain line ■ in Fig. 1, Fig. 4 is an arrow view taken along the IV-■ line in Fig. 3, and Fig. 5 is an enlarged view of the part indicated by the chain line ■ in Fig. 1. Figure 6 is a view taken along the line ■-■ in Figure 5, Figure 7 is an enlarged sectional view of the part indicated by the chain line ■ in Figure 1, and Figure 8 is pressure suppression in a boiling water reactor. It is a front sectional view showing a chamber. 1... Torus shell, 2... Pressure suppression chamber, 3... Vent pipe, 4... Vent header, 5... Downcomer, 6... Rail, 7... Scaffolding device, 8... Scaffolding frame, 9... Scaffolding board, 10... Horizontal frame,
11... Vertical frame, 12A-12B...
Rod, 13... Connecting pipe, 14... Clamp, 15... Mounting pipe, 16... Support piece, 17... Hinge, 18... Connection piece, 19... Support plate, 20... Holding member, 21... Bolt, 22... Stopping plate, 23 ...hole, 24 ... claw, 25.
...Mounting section, 26...Vertical plate, 27...
... Reinforcement plate, 28 ... Backing plate, 29 ...
・・Hanging tool, 30A・30B・・・Rod, 31
......Connecting member, 32...Bolt, 33
... Clamp fitting, 34 ... Auxiliary arm, 35 ... Chain, 36 ... Handrail, 37 ... Connection rod. Applicant Ishikawajima Harima Heavy Industries Co., Ltd. Toshiba Corporation Figure 1

Claims (1)

[Claims] This is a scaffolding device used when carrying out construction work in the pressure suppression chamber inside the torus shell of a nuclear reactor, in which multiple scaffolding boards are arranged at mutual intervals in the circumferential direction of the pressure suppression chamber and scaffolding boards are placed between them. The scaffold frame is formed into a gate shape with vertical frames arranged at both ends of the horizontal frame, and a clamp fixed to the rail on the upper wall of the torus shell is attached to the horizontal frame. , a mounting part placed on a vent header along the circumferential direction of the pressure suppression chamber is provided spaced apart in the horizontal direction, and the vertical frame is suspended from the horizontal frame placed on the vent header. 1. A scaffolding device for a pressure suppression chamber of a nuclear reactor, characterized in that the scaffolding device has a length that separates from the inner bottom surface of a torus shell when the scaffolding device is turned off.