Steam generator shell parting method and apparatus

摘要

A method and apparatus for effecting within a nuclear power plant horizontal separation of the vertically-extending cylindrical wall of the shell of a steam generator by an accurate cutting technique that generates a weld accommodating profile in preparation for subsequent rejoining. This is attained by progressive installation of horizontal hinged-section tension band assemblies around the shell, adding vertical anchor members clamped to the bands at circumferential intervals therearound, hanging and locking track support brackets onto the anchor members, assembly of a multiple-section rigidized circular track onto the support brackets and around the shell, vertically and radially adjusting and locking the track in place, roller mounting a carriage-supported milling machine assembly on the track, and taking a series of tapered milling cuts in the shell wall while the milling machine assembly is moved along the track by use of gear teeth thereon.