1. Field of the Invention
This invention relates to retubing a nuclear steam generator and more particularly to retubing a nuclear steam generator, while it is vertically oriented in a containment vessel.
2. Description of the Prior Art
Two allowed applications entitled, "Methods for Retubing a Steam Generator" were filed by the assignee of this invention on Feb. 2, 1977 and Sept. 19, 1977, and were given the respective Ser. Nos. 765,030 now U.S. Pat. No. 4,135,701 granted Jan. 23, 1979, and 834,855. These applications describe early conceptual methods of retubing. The method described hereinafter is a refinement of these earlier methods and has the advantage of being a method, which was tested on an actual steam generator disposed in a simulated containment vessel. The steps have been refined and set in a particular order to complete retubing and upgrading a steam generator in a time frame of 62 to 77 days without exposing personnel to excessive levels of radiation.