Ultrasonic probes for inspection of reactor pressure vessel bottom head and weld buildup thereon
US5460045A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 9, 1993 |
| Grant date | Oct 24, 1995 |
| Priority date | — |
| Expiry date | Aug 9, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E30/30
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An improved method for repair of incore-instrumentation-housing and related defects in a nuclear reactor system involves three stages, each with ultrasonically assisted inspections. In the first stage, a defective incore housing is removed and the exposed area and aperture at the former location of the incore housing is ultrasonically inspected using an ultrasonic probe with a tiltable disk-shaped head that self-conforms to the local contour of the reactor vessel bottom. In the second stage, a weld buildup is formed. The reactor is then sealed and the weld buildup is machined to define an aperture therethrough. The weld buildup is then ultrasonically inspected with a second probe with a centering member that is stationary as the probe body is moved vertically relative to it. In the third stage, a J-prep is formed. A new incore housing is inserted through the weld buildup aperture. The new incore housing is welded at the J-prep. The J-weld is ultrasonically inspected using a third ultrasonic probe. The new incore housing is then connected to the incore guide tube with shrink couplings, and reactor activity can be restored.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.