System for removing and installing a control rod drive
US4973443A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 26, 1988 |
| Grant date | Nov 27, 1990 |
| Priority date | — |
| Expiry date | Oct 26, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E30/30
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A system for removing and installing a control rod drive from a drive housing mounted in the vessel of a boiling water reactor. The system comprises a carriage supported by and movable along the service rails normally present in the undervessel cavity, and a cradle pivotally connected to the carriage and having a length substantially less than the length of a control rod drive. The pivot point between the cradle and the carriage is chosen such that the length of the carriage is subsumed within the length of the cradle when the cradle is pivoted into a horizontal position. The pivoting movement is accomplished by means of a hydraulic cylinder connected between one end of the carriage, and the upwardly-swinging end of the cradle. The cradle includes a lifting and lowering mechanism formed by the combination of a leadscrew drive and a hydraulic cylinder. The hydraulic cylinder is slidably connected to the cradle so that it is movable between a recess within the cradle when not in use to a position directly beneath and in tandem with the control rod drive when in use. The lifting and lowering mechanism can move a control rod drive from a position coterminous with the bottom end of the …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.