Title:
SHIELDED ACCESS DOOR OF MANHOLE
Document Type and Number:
Japanese Patent JP3042661
Kind Code:
B2
Abstract:
PURPOSE: To provide a lightweight shielded access door allowing easy lifting up of a manhole door and other operations by a maintenance worker.
CONSTITUTION: This shielded access door includes a bracket 210 connected to a flange 152 of a manhole and a plurality of oscillating arms 270 having a first end portion 280 pivotally mounted on the bracket 210. A first shield plate 340 is connected to a second end portion 320 of the arm 270 and is disposed adjacent to the manhole in parallel. The first shield plate 340 and the manhole define a gap 460. The first shield plate 340 has a ventilation hole 350 for ventilating the manhole and discharges air-borne radioactive particles 355. A second shield plate 360 mounted on the first shield plate 340 is coaxially aligned with the ventilation hole of the first shield plate 340 and is separately disposed from the first shield plate 340 for preventing the beam of radiation from exiting through the ventilation hole. The first shield plate 340 is formed of lightweight connectable segments.
Inventors:
David Michael Evans
Ricky El Tucker
John Oh Isso
Ricky El Tucker
John Oh Isso
Application Number:
JP22469493A
Publication Date:
May 15, 2000
Filing Date:
September 09, 1993
Export Citation:
Assignee:
WESTINGHOUSE ELECTRIC CORPORATION
International Classes:
F16J13/20; F22B1/16; F22B37/22; G21C17/003; G21D1/00; G21F3/00; G21F7/005; (IPC1-7): G21C17/003; F16J13/20; F22B1/16; G21D1/00; G21F3/00
Domestic Patent References:
| JP3186798A | ||||
| JP28563A | ||||
| JP63253297A | ||||
| JP6293572A | ||||
| JP5810290A | ||||
| JP2280096A |
Attorney, Agent or Firm:
Soga Doteru (6 people outside)
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