JPS5815757B2 - Automatic decontamination equipment for stainless steel pits at nuclear power plants - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic decontamination device for stainless steel pits in nuclear power plants.

Decontamination work for stainless steel pits has traditionally been done manually.

When it is done manually, it is done using scaffolding or on a gondola.

In the case of gondolas, they were extremely unstable due to the reaction forces of decontamination work, and therefore required a very long construction period.

Another drawback was that sufficient decontamination could not be carried out because it involved dangerous work.

In consideration of the tendency of upward movement, the present invention allows the decontamination device to be moved while adsorbing it to the wall surface using a vacuum effect to receive its own weight and the reaction force of the decontamination brush, making it possible to decontaminate the entire wall surface with a uniform force. The present invention aims to provide an automatic decontamination device that is easy to use, and embodiments thereof will be described below with reference to the attached drawings.

FIG. 1 shows a worker M using an automatic decontamination device A according to the present invention.
The pit wall 1 is being decontaminated by remote control.

The decontamination device A runs on a stainless steel wall 1 in any direction using four wheels 2, 2a.

3 is a winch suspended by a crane (not shown) that winds and unwinds rope 4 in synchronization with decontamination equipment A, which is a nuclear power plant whose mission is to reduce the length of radiation exposure as much as possible. The safety of decontamination equipment at power plants is ensured.

The decontamination device A is equipped with a suction device 5 of a special structure, which will be described later, and is configured to travel while adsorbing the wall surface 1 by vacuum action.

Reference numeral 6 denotes a suction pipe leading to the adsorption device 5, which in turn communicates with the blower 8.

7 is a tower containing a demister and a filter, and 9 is a siren chi.

A plunger pump 10 supplies pressurized water to a cleaning rotating brush 23 provided in the decontamination apparatus A through a water supply pipe 10'.

The cleaning rotary brush sprays water onto the wall surface 1 when it rotates, and the water is covered with a hood to prevent it from scattering around and is discharged through a drain pipe 11.

Reference numeral 12 denotes a hand-held operation panel, which is operated by worker M as an auxiliary operation panel 12a.
remotely controlled via.

13 is a main control panel, which communicates with the auxiliary operation panel 12.

Referring to FIGS. 2 and 3, 42 is a frame of the decontamination apparatus A.

The wheels 2 on the lower side of the figure are drive wheels attached to an axle 14 supported by a machine frame 42, and include a sprocket 15 and a chain 16.
, are driven by a guard moke 18 via a sprocket 17.

On the other hand, the wheel 2a on the upper side of the figure can change direction freely via a lever 20 and a steering rod 21 by a power cylinder 19.

Note that the right wheel 2a is operated by the connecting rod 22 at the same time as the left wheel.

Reference numeral 23 denotes a rotating brush for cleaning, which is supplied with water through a water supply pipe 10' and sprays water onto the wall surface 1 to clean it.

The cleaning rotating brush 23 is driven by a motor 24 → belt 25 → pulley 26.

Reference numeral 27 denotes a hood for the cleaning rotating brush 23, which prevents the sprayed water from scattering and communicates with the drain pipe 11 at the lower center.

The cleaning rotating brush 23 can be moved toward and away from the wall surface by a power cylinder 28 → sliding mechanisms 29, 30, and 31.

In this way, the rotating brush 23 can be moved toward and away from the link mechanism and the power cylinder 28, so when adhering the decontamination device to the wall surface prior to cleaning, keep the rotating brush away from the wall surface to ensure that the decontamination device is firmly attached to the wall surface. After attracting the dyeing device, gradually press the rotating brush against the wall surface.

By doing this, it can be firmly adsorbed to the wall surface without being interfered with by the rotating brush.

Since it is firmly adsorbed in this manner, a powerful drive device is required to move this decontamination device, but the drive wheels 2 allow it to be moved freely.

Reference numeral 32 denotes a power cylinder, which allows the draining sweeper 33 to be swung.

As shown in FIGS. 4 and 5, the suction device 5 attaches a suction leaf 34 made of an elastic material such as urethane to a disk 35.
It has a suction cup fixed to its periphery.

For example, 36 suction leaves 34 are arranged around the disk 35, and the suction leaves are placed on the sides of each other so that a vacuum can be created in the space surrounded by the suction leaves 34, the disk 35, and the stainless steel wall 1. are close together.

The suction leaf 34 has a mounting hole 37 in the mounting portion 36 as shown in FIG. 4, has a wide peripheral edge, that is, a trapezoidal planar shape, and has an angular shape in vertical section as shown in FIG. .

38 is a reinforcing rib, and 39 is a positioning rib provided on the mounting portion 36.

The contact edge 40 of the suction leaf 34 is thick and has a convex circular cross section in order to contact the wall surface 1 and easily maintain airtightness.

Reference numeral 41 (FIG. 2) is a constant-pressure Fukamochida automatic valve, which maintains the degree of vacuum in the space surrounded by the suction leaf 34 at an appropriate value.

Decontamination equipment A with the above configuration does not require building scaffolding or riding an unstable gondola as in the past.
As shown in Fig. 1, the system can be operated remotely by a single worker from a position outside the pit that is safe from radiation exposure, making it extremely safe and speedy.

In particular, since the decontamination device A runs while being vacuum-adsorbed against the wall surface, the cleaning brush can perform decontamination with uniform pressure.

Since the traveling device of the decontamination equipment can change direction, even if there are obstacles on the wall, it can be easily avoided and the equipment can travel in any direction.

The suction device is composed of a large number of elastic suction leaves, each of which has an F-shaped cross section, and the cross-sectional shape of the edge that contacts the wall is thick and has a convex arc shape. Vacuum leakage will never be a problem even if there are irregularities on the wall surface, and the suction leaf partially bends and buffers even the slightest irregularity on the wall surface, so decontamination work can be carried out smoothly.

In addition, since the traveling device is mounted on the machine frame, even if a strong vacuum acts on the suction device, there will be no effect on the tubes, and the mission is to minimize radiation exposure at nuclear power plants.Decontamination of nuclear power plants This makes it possible to operate the equipment safely and efficiently.

[Brief explanation of the drawing]

FIG. 1 shows a pit wall surface being decontaminated using the decontamination apparatus according to the present invention. Figure 2 is a front view of the decontamination equipment; Figure 3 is a left side view of Figure 2;
FIG. 4 is a plan view of the suction leaf. FIG. 5 is a cross-sectional view taken along the line ■-■ in FIG. In the figure, A: Automatic decontamination equipment, 1: Wall surface (of the pit), 2: Drive wheel, 3: Winch, 4:
... Rope, 5... Adsorption device, 6... Suction pipe,
7... Tower (with built-in demister and filter), 8...
Blower, 9... siren chi, 10... plunger pump, 10'... water supply pipe, 11... drain pipe,
12... Hand operation panel, 12a... Auxiliary operation panel, 13
...Main control panel, 14...Axle, 15...Sprocket, 16...Chain, 17...Sprocket,
1B... Guard motor, 19... Power cylinder, 20... Lever, 21... Steering rod,
22... Connecting rod, 23... Rotating brush (for cleaning),
24... Motor, 25... Belt, 26... Pulley, 27... Hood, 28... Power cylinder,
29. 30, 31... Link mechanism, 32... Power cylinder, 33... Draining sweeper 134... Adsorption leaf, 35... Disc, 36... Mounting part, 37...
...Mounting hole, 3B...Reinforcement rib, 39...Rib for preventing slippage, 40...Edge (of suction leaf), 41...
・Automatic valve, 42... Machine frame.

Claims (1)

[Claims] 1 At the periphery of the disk, elastic suction leaves having a trapezoidal planar shape, an F-shaped longitudinal section, and a thick, convex arc-shaped cross-sectional shape at the edge contacting the wall surface are placed on both sides. Using a crane, etc., the machine frame is equipped with a suction device consisting of a plurality of suction plates fixed so that their edges are closely spaced, a suction pipe and a blower that evacuate the space surrounded by the disk, suction leaf, and surface to be decontaminated. A water spray injection device is mounted on the suspended machine frame, a rotating brush that can be moved in and out using a power cylinder equipped with a drain sweeper and a hood that connects to the drain pipe, and a traveling device equipped with drive wheels are remotely controlled. An automatic decontamination device for stainless steel pits in nuclear power plants, which is characterized by the following features: