Patent · US Expired

Repair of incore housings using ultrasonic examinations

US5272734A · kind A · utility

8Cited by
4References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 9, 1992
Grant dateDec 21, 1993
Priority date
Expiry dateApr 9, 2012

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.