JPH0573000B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a method and apparatus for dismantling a concrete wall of a nuclear reactor.

(Problem) To dismantle and remove a nuclear reactor, the concrete heat-shielding reactor wall contaminated with radioactivity must be cut away while completely protecting human bodies and the atmosphere. Therefore, it is necessary to accurately cut the concrete heat-shielding furnace wall according to a predetermined procedure, and to mechanically grasp and transport the cut furnace wall. Moreover, unless the cutting work, carrying out work, and accompanying carrying out and replenishment of equipment are carried out efficiently, it will take an unnecessarily long working period and incur enormous costs.

(Object and outline of the invention) The present invention has been devised in view of the above points, and
The present invention provides a demolition method and apparatus for safely and mechanically cutting, grasping and transporting concrete heat shielding walls of a nuclear reactor.

That is, in the nuclear reactor dismantling method of the present invention, a table is raised and lowered via a main shaft suspended inside the reactor cavity, and this table has vertical,
A horizontal stocker exchange device and a gripping and conveying device are provided, and a peeling device peels the block-shaped furnace wall from the furnace wall and waits at a predetermined position, the gripping and conveying device grips and conveys it, and at the same time, the empty space consumed by the cutting operation is removed. This is a construction method in which a burning burst stocker and a new burning burst stocker are replaced using vertical and horizontal stocker exchange equipment, and the above construction procedure is repeated to perform sequential cutting work.The suitable demolition equipment used to carry out this demolition method is A main shaft is suspended in the cavity via an elevator at the top of the gantry, and a table is provided so that it can be raised and lowered via this main shaft, and a gripping and conveying device, a horizontal stocker changing device, and a vertical stocker changing device are installed on the underside of the table. In addition, a vertical cutting device and a horizontal cutting device are fixed to the lower part of the main shaft, and a peeling device is further provided on the upper surface of an outrigger provided at the lower end of the main shaft.

With the above method and equipment, nuclear reactor dismantling work can be carried out safely and efficiently.

(Example) Hereinafter, the nuclear reactor dismantling method and apparatus of the present invention will be specifically explained based on the drawings.

FIG. 1 is a schematic side cross-sectional view illustrating a nuclear reactor dismantling system. This disassembly system includes an enclosure built on top of the reactor 1 for radiation shielding, a gantry frame 10 provided within the enclosure, an elevator 11 disposed above the gantry frame 10, and a The main shaft M is suspended in the cavity 12 of the nuclear reactor via the main shaft M. Gantry frame 10,
The elevator 11 and the main shaft M constitute the main support and drive section in the demolition system of the present invention. The gantry frame 10 is a U-shaped frame member that closes the cavity 12 from above. In addition, the elevator is connected to the gantry frame 10.
The main shaft M is fixedly installed on the upper surface of the main shaft M, and the main shaft M itself is raised and lowered by an elevating cylinder and rotated in the horizontal direction by a swivel table. Moreover, the main shaft M is fixed at a predetermined position in a locked state. Further, at the lower part of the gantry frame 10, a closing floor plate (not shown) is provided which can be opened and closed by a hydraulic cylinder or the like.

FIG. 2 is a schematic side view showing the fixed state of the vertical and horizontal cutting devices 2 and 3 and the peeling device 4, and FIG.
FIG. 3 is a plan view taken along line A-A in the figure.

A vertical cutting device 2 and a horizontal cutting device 3 are each fixed to the lower part of the main shaft M, and both the cutting devices 2 and 3 are offset from the axis of the main shaft M and are out of phase by approximately 180°. Fixed. Furthermore, both of them are formed to be able to pivot in the horizontal direction. In order to cut the furnace wall W into circular slices, the transverse cutting device 3 has a structure in which it can be moved up and down within a predetermined stroke using a main shaft M as a guide by an elevating motor (not shown). Furthermore, the vertical and horizontal cutting devices 2 and 3 can be expanded and contracted in the horizontal direction by respective booms 21 and 31, and also have elevation cylinders 22 and 23.
The angle can be adjusted in the vertical direction. On the other hand, an outrigger O is installed at the lower end of the main shaft M to prevent the main shaft M from swinging during cutting work or when carrying out the cutting block. Furthermore, a peeling device 4 is provided on the upper surface of the outrigger O as shown in FIG. As shown in the schematic side view of FIG. 4, the peeling device 4 includes a base 41, a boom 42,
It is formed by an arm 43 and a hand portion 44 provided at the tip of the arm 43.

That is, the boom 42 and the arm 43 are extended and advanced by the drive cylinder, and the hand portion 44 is moved toward the furnace wall W.
get closer to And the cut-out block-shaped furnace wall
The WB (hereinafter referred to as the cutting block) is connected to the hand section 44.
, and the boom 42 and arm 43 are driven to move the hand section 44 backward. At this time, when the hand section 44 is swung, the predetermined cutting block WB is easily peeled off from the furnace wall W. Further, as shown in FIG. 5 (a plan view taken along the line B-B in FIG. 2), this peeling device 4 is structured so that it always holds the cutting block at a fixed position relative to the main shaft M and waits. .

FIG. 6 is a schematic side view illustrating each device for gripping and transporting a cutting block and exchanging the burning burst stockers of the longitudinal and transverse cutting devices. A table T is provided on the main shaft M so as to be movable up and down. This table T is constructed by suspending a wire r between a winch W and a sheave block b provided on the lower surface of the elevator 11 and a sheave block b fixed to a rotating device or a lifting device on the upper surface of the table T, and is driven by the winch W. The main shaft M is used as a guide to move up and down. Furthermore, a gripping and conveying device 5, a vertical stocker changing device 6, and a horizontal stocker changing device 7 are provided on the lower surface of the table T, respectively.

7a, b, and c are schematic side views of the carry-out gripping and conveying device 5, the vertical stocker changing device 6, and the horizontal stocker changing device 7.

The gripping/unloading device 5 detects the position of the cutting block using a limit switch or the like, and grips the cutting block using a link motion of the hand portion 51. Further, vertical movement is performed by a slide cylinder 52, and horizontal movement is performed by an elevation cylinder 53. The vertical stocker replacement device 6 lifts up the empty burning burst stocker consumed by the vertical cutting device 2 and attaches a new burning burst stocker to the cutting device 2. Therefore, the hand section 61, the slide cylinder 62 that moves in the vertical direction, and the elevation cylinder 6 that moves in the horizontal direction.
3, and a rotating device m is provided on the upper part so that it can rotate around an axis.

On the other hand, the horizontal stocker replacement device 7 also removes the empty burning burst stocker consumed by the horizontal cutting device 3, and suspends and attaches a new burning burst stocker. It consists of a hand part 71 that suspends each burning burst stocker, a hoist device 72 that moves the hand part 71 in the vertical direction, and a rotation motor 73 that moves the hand part 71 in the horizontal direction.

The construction of dismantling a nuclear reactor wall using the dismantling apparatus having the above configuration will be described below.

First, the main shaft M is placed in a predetermined position within the cavity using the elevator 11. If the reactor type has a substantially perfect circular flat cross section, the reactor wall can be uniformly cut even when the main shaft M is installed at the center of the reactor diameter and fixed to the gantry 10.

In this state, the outriggers O are extended and installed between the furnace walls W to support the main shaft M. Next, the support drive parts of the vertical and horizontal cutting devices 2 and 3 are operated from the central operator's cab or the like. That is, vertically,
The current positions of the transverse cutting devices 2 and 3 are read, and the cutting location is specified based on the cutting order analyzed in advance. First, at the first cutting location, the burning bar of the transverse cutting device 3 is ignited to perforate the furnace wall W in a horizontal ring shape. The vertical cutting device 2 performs back and side holes on the horizontal ring-shaped portion. Next, the peeling device 4 is rotated toward the cutting location, and the cutting block WB is grasped by the hand portion 44 using a mamming motion driven by each cylinder, and is peeled from the furnace wall W. Then, while holding the cutting block WB, it is moved to a predetermined position from the main shaft M and placed on standby. When the above-mentioned cutting operation and peeling are completed and the standby state is reached, the table T is lowered via the main shaft M. Cutting block with the gripping and conveying device 5 installed on the underside of the table T waiting
Detects and grasps the WB. Almost simultaneously, the vertical and horizontal stocker exchange devices 6 and 7 grasp the empty burning burst stockers of the vertical and horizontal cutting devices 2 and 3 that have been consumed in the cutting operation, and then the table T is raised. The table T rises to a predetermined position and drops the cutting block WB into the block container fed out from the loading/unloading lock device 13. When a predetermined amount of cutting blocks WB, WB, etc. are dropped into the container, the lid is closed and the container is transported outside. On the other hand, the stocker changing devices 6 and 7 open the empty burning burst stocker,
Grab the new Burning Burst Tsuka. Then, the table T is lowered, and new burning burst stockers are attached to the vertical and horizontal cutting devices 2 and 3, respectively, by its rotation and horizontal movement. The cutting operation is carried out by gripping and transporting the cutting block described above and exchanging the burning bar.

In other words, since the table T that moves up and down along the main shaft M is provided with a gripping and conveying device and a vertical and horizontal stocker changing device, cutting blocks can be
It becomes possible to carry out the work of transporting the WB and the work of replacing the stocker almost at the same time.

When a certain amount of the furnace wall is cut during the cutting operation, slag falls and accumulates at the bottom of the furnace, so this slag is collected by a recovery device, lifted by a slag bucket, and transported to the outside of the gantry via a loading/unloading lock device. to be carried out.

(Effects of the Invention) As described above, the nuclear reactor dismantling method and the device of the present invention are particularly suitable for cases where the planar cross section of the reactor type is approximately a perfect circle and is not very large in diameter, and is suitable for horizontally moving the main shaft. The cutting operation, the gripping and conveyance of the cutting block, and the replacement of the empty burning burst stocker and the new burning burst stocker are performed mechanically.

As a result, cutting work and removal of cutting blocks can be carried out while completely protecting the human body and the atmosphere from radioactive contamination, and replenishment and removal of equipment can be carried out continuously and smoothly, greatly shortening construction time. Ru. This can also significantly reduce overall disassembly and removal costs.

[Brief explanation of the drawing]

Figure 1 is a side cross-sectional schematic diagram illustrating the demolition system, Figure 2 is a vertical cross-sectional view illustrating the demolition system;
3 is a schematic side view showing the cutting device and the peeling device; FIG. 3 is a plan view taken along line A-A in FIG. 2; FIG. 4 is a schematic side view of the peeling device; FIG. 5 is a side view schematically showing the peeling device in FIG. A plan view taken along line B-B, and FIG. 6 is a schematic side view illustrating each device provided on the underside of the table.
7a, b, and c are schematic diagrams of the gripping and conveying device, the vertical stocker changing device, and the horizontal stocker changing device. 1... Nuclear reactor, 10... Gantry, 12...
Cavity, 13... Loading/unloading lock device, T...
Table, 2... Vertical cutting device, 3... Horizontal cutting device, 5... Grasping and conveying device, 6... Vertical stocker changing device, 7... Horizontal stocker changing device, 4... Peeling device, M... Main shaft , W... Furnace wall, WB...
... Cutting block, O... Outrigger.

Claims (1)

[Claims] 1. A gantry is provided in the reactor, and a table is raised and lowered from an elevator at the top of the gantry via a main shaft suspended in the cavity, and a vertical and horizontal cutting device provided at the bottom of the main shaft is used to raise and lower the table. In a demolition method in which the furnace wall is cut into blocks, the burning burst stocker is replaced by a vertical and horizontal stocker exchange device installed on the underside of the table, and the block-shaped furnace wall is carried out by a gripping and conveying device, the cut blocks are The shaped furnace wall is peeled off from the furnace wall and gripped by a gripping and conveying device, and the empty burning burst stocker of the vertical and horizontal cutting device consumed by the above cutting is gripped by a stocker changing device and the table is raised to a predetermined position. Then, the block-shaped furnace wall and the empty burning burst stocker are carried out to the outside through the carry-in/out lock device, and the table is set in a predetermined position while the new burning burst stocker carried into the cavity is held by the vertical and horizontal stocker exchange devices. A nuclear reactor dismantling method in which the reactor is lowered to a new position, the new burning bar is attached to a vertical and horizontal cutting device, and the reactor wall is cut by injection combustion of the burning bar. 2. A gantry is provided in the upper part of the reactor, a main shaft is suspended in the cavity via an elevator above the gantry, a table is provided so as to be movable up and down via the main shaft, and the lower surface of the table is equipped with a gripping and conveying device and a horizontal stocker. Nuclear reactor dismantling characterized in that a replacement device and a vertical stocker replacement device are provided, a vertical cutting device and a horizontal cutting device are fixed to the lower part of the main shaft, and a stripping device is provided on the upper surface of the outrigger provided at the lower end of the main shaft. Device. 3. The nuclear reactor dismantling apparatus according to claim 2, wherein the main shaft is suspended approximately at the center of the cavity of the reactor. 4. The nuclear reactor disassembly apparatus according to claim 2, wherein both the vertical cutting device and the horizontal cutting device are fixed at positions offset from the central axis of the main shaft.