Patents Examined by Dan Matz
  • Patent number: 6834092
    Abstract: The method facilitates sealing a control rod drive (CRD) housing to a stub tube in a reactor pressure vessel of a nuclear reactor, if any cracks develop proximate a heat affected zone of the stub tube at a CRD housing re-attachment weld. The method includes cutting the CRD housing to separate an upper portion of the CRD housing from a lower portion of the CRD housing. The lower portion remains in place and in substantial alignment with the upper portion of the CRD housing. A lower portion member, which may be the lower portion that was cut, is re-attached to the reactor vessel by a re-attachment weld at a location below potential differential leakage paths along the CRD housing. The heat affected zone (e.g., at the re-attachment weld) is covered with a corrosion resistant material to prevent future leaking, and to protect the weld from inter-granular stress corrosion cracking (IGSCC).
    Type: Grant
    Filed: July 15, 2002
    Date of Patent: December 21, 2004
    Assignee: General Electric Company
    Inventors: Eric R. Willis, Sampath Ranganath, Paul Van Diemen