Opening and closing device for access port that opens to working platform of reactor vessel

Patent metadata

Field	Value
Publication number	US-9601221-B2
Application number	US-201013263468-A
Country	US
Kind code	B2
Filing date	Jun 8, 2010
Priority date	Jul 10, 2009
Publication date	Mar 21, 2017
Grant date	Mar 21, 2017

Abstract

An opening and closing device that opens and closes an access port opened from a substantially cylindrical working platform disposed inside a reactor vessel and used to access a nozzle stub of the reactor vessel from the inside of the working platform, the opening and closing device includes: a cover that is slidable along an outer peripheral surface or an inner peripheral surface of the working platform from a closing position where the access port is closed to an opening position where the access port is opened; and moving device for sliding the cover.

First claim

The invention claimed is:

1. A substantially cylindrical working platform provided with an opening and closing device,
wherein the working platform is configured for arrangement inside a nuclear reactor vessel, and
wherein the working platform is useable to access a nozzle stub of the nuclear reactor vessel from the inside of the working platform,
wherein the working platform comprises a plurality of access ports spaced in a circumferential direction of the working platform,
wherein the opening and closing device is arranged to open and close the plurality of access ports,
wherein the opening and closing device comprises:
a single unitary cover,
wherein the cover is disposed in the circumferential direction,
wherein the cover is formed in an annular shape along the circumferential direction, and

a moving device operable to move the cover,
wherein the moving device is operable to cause the cover to slide along an outer peripheral surface of the working platform from a closing position where the plurality of access ports are closed to an opening position where the plurality of access ports are open, and

wherein the cover is slidably movable to simultaneously open the plurality of access ports,
wherein the cover is slidably movable to simultaneously close the plurality of access ports.

2. The opening and closing device according to claim 1 ,
wherein the cover is movable in the vertical direction.

3. The working platform according to claim 1 ,
wherein the cover is movable in the circumferential direction.

4. The working platform according to claim 1 ,
wherein the cover is provided in the outer peripheral surface of the working platform.

5. The working platform according to claim 1 , wherein
the opening and closing device further comprises a sealing unit, wherein
the sealing unit is provided between the cover and the working platform, and
the sealing unit seals a peripheral edge of the access port while the cover closes the access port.

6. The working platform according to claim 5 ,
wherein the sealing unit includes a sealing member that is provided in one of the cover and the working platform and advances toward the other thereof to come into close contact therewith.

7. The working platform according to claim 6 ,
wherein the sealing member is formed in a bag shape so as to be expanded by supplying a fluid thereinto to advance toward the other of the cover and the working platform and come into close contact therewith.

8. The working platform according to claim 6 ,
wherein the sealing member is a substantially plate-shaped member that advances from the cover toward the working platform to close the access port.

9. The working platform according to claim 8 ,
wherein the cover is provided in the outer peripheral surface of the working platform, and a passage is formed at a position of the cover facing the sealing member to communicate with the outer periphery.

10. The working platform according to claim 8 , further comprising an independent foamed body, wherein
the independent foamed body is provided in a surface of the sealing member facing the working platform, and
the independent foamed body surrounds the access port.

Assignees

• Sugiura Atsushi
• Hori Takumi
• Nishikawa Kenji
• Onishi Ken
• Shimonabe Noriaki
• Tsuzuki Satoshi
• Wakamoto Ikuo
• Mitsubishi Heavy Ind Ltd

Inventors

• Sugiura Atsushi
• Hori Takumi
• Nishikawa Kenji
• Onishi Ken
• Shimonabe Noriaki
• Tsuzuki Satoshi
• Wakamoto Ikuo

Classifications

• G21C19/02 Primary

  Details of handling arrangements · CPC title

• G21C19/207

  Assembling, maintenance or repair of reactor components (G21C3/334 takes precedence) · CPC title

• Y02E30/40

  Cross-Sectional Technologies · mapped topic

• G21C13/00

  Pressure vessels; Containment vessels; Containment in general (for chemical or physical processes B01J3/00; pressure vessels in general F16J12/00) · CPC title

• G21C13/0285

  for container apertures · CPC title