Reactor internals through-hole grapple
US4919881A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 5, 1988 |
| Grant date | Apr 24, 1990 |
| Priority date | — |
| Expiry date | Jul 5, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E30/30
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A remotely operated device which attaches to an existing internals lifting rig to safely lift and transport nuclear reactor internals structures. The device includes a grapple assembly uniquely formed to maximize the effective bearing surface of an annular shoulder disposed on the grapple assembly to engage the internal structure. The annular shoulder comprises a first outer diameter, the annular shoulder defining a second outer diameter disposed thereabove. The grapple assembly comprises a plurality of fingers circumferentially disposed about an actuator rod which has a diameter essentially equal to a first inner diameter of the grapple assembly. The lower end of the grapple assembly has a second inner diameter smaller than the first and axially adjacent to the annular shoulder. In order to maximize the bearing surface, the fingers of the grapple assembly are formed such that the first inner and outer diameters are machined with respect to a first axis, whereas the second inner and outer diameters are formed with respect to a second axis parallel to the first. These machining axes are offset from each other by a distance which is equal to the desired amount of radial expansion of …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.