JPS6324480Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cleaning tool for peeling off deposits on the bottom of a shielded tank in nuclear reactor equipment that is difficult to access.

Conventionally, brushes and cutters with wheels or brushes and cutters attached to a rotating shaft equipped with a frame have been used for cleaning deep tank bottoms. However, with the former, it is difficult to position the tip of the brush or cutter.
The latter requires large-scale equipment, and is often adaptable depending on the site.

The present invention utilizes the flexibility of the chain to provide a cleaning tool that can clean the tank bottom of nuclear reactor equipment without accurate positioning of the tip of the chain.Examples will be described below.

1 is a waste storage tank for nuclear reactor equipment that is deep and shielded from above so that it cannot be seen visually. 2 is a cleaning tool according to the present invention. The cleaning tool 2 has a flexible shaft 4 that is concentrically and rotatably provided in a grip handle 3 that projects outside the top wall of the waste storage tank 1, and a rotary plate 5 is attached to the lower end of the flexible shaft 4. ing. A plurality of chains 6 are attached to the lower surface of the rotating plate 5, and are made of a material such as metal, plastic, or nylon mixed with an abrasive material. The flexible shaft 4 is supported by a bearing 7 within the gripping handle 3, and is driven via the flexible shaft 4 by a motor 8 provided outside the tank. Although the grip handle 3 is not shown, it goes without saying that an auxiliary support device is required. Note that 9 is a cover for the rotary plate provided at the lower end of the grip handle 3, and when it comes close to a wall surface, this comes into contact first and can prevent the rotary plate from directly hitting the wall surface.

Now, when trying to clean the deep bottom of a nuclear reactor facility, the top is covered with a lead lid, so you can't see from the top at all. Therefore, when the grip handle 3 is supported by an appropriate support device and the rotating plate 5 is rotated by the motor 8, the chain 6 is rotated. The chain 6 opens like an umbrella depending on the rotation speed, and at this time, the lower end of the chain comes into contact with the bottom of the tank, making it possible to remove deposits attached to the bottom of the tank.

In this case, since the chain is flexible, cleaning can be done safely without damaging the bottom of the tank even if the distance between the chain and the bottom of the tank is not so strict.

Furthermore, since a cover is provided at the lower end of the gripping handle to cover the rotary plate, it is possible to prevent the rotary plate from being damaged by hitting the side wall.

When the number of revolutions of the rotary plate is increased, the chain becomes stiffer, and when the number of revolutions of the rotary plate is decreased, it becomes softer and looser, so it can be adjusted according to the density of the sediment at the bottom of the tank.

By changing not only the number of rotations but also the material of the chain, it is possible to adapt to a wide range of properties such as the nature of deposits and the degree of cleaning finish.

[Brief explanation of the drawing]

The figure is a sectional view of cleaning according to the present invention. In the diagram; 1...tank, 2...cleaning tool, 3...
Gripping handle, 4... Flexible shaft, 5... Rotating plate, 6...
Chain, 7...Bearing, 8...Motor, 9...Cover.

Claims (1)

[Claims for Utility Model Registration] 1. A rotary plate 5 having a plurality of chains 6 attached to its lower surface;
A gripping handle 3 is supported by an appropriate support device so that its top protrudes outside the tank, and has a cover 9 for a rotary plate 5 at its lower end; a flexible shaft 4 rotatably supported within the gripping handle 3; A tank bottom cleaning tool for nuclear reactor equipment comprising a flexible shaft 4 and a motor 8 that can be driven outside the tank. 2. A tank bottom cleaning tool for nuclear reactor equipment as set forth in claim 1 of the utility model registration claim, characterized in that the chain is made of metal. 3. A tank bottom cleaning tool for nuclear reactor equipment as set forth in claim 1 of the utility model registration claim, characterized in that the chain is made of plastic. 4. The tank bottom cleaning tool for nuclear reactor equipment according to claim 1, wherein the chain material is a mixture of abrasive material and nylon.