Patent ID: 8622696

Claim:
A method for locking together first and second axially adjacent rotor sections of a steam turbine, including a first rotor section having a threaded boss that axially extends from and is concentric with an axis of rotation of the first rotor section and a second rotor section having a tapped cavity that is configured to screwingly receive the threaded boss, wherein the threaded boss and tapped cavity comprise components of a primary join, the method comprising: a) forming a first locking cavity, non-concentrically with the axis of rotation of the first rotor section, the first locking cavity being provided for receiving a locking member therethrough, the first locking cavity being formed through one of the rotor sections to a rotor section surface that at least partially contacts a rotor section surface of the other rotor section when the primary join is formed; b) forming the primary join by joining, either before or after a) the threaded boss and tapped cavity, together; c) forming a second locking cavity from the first locking cavity, after a) and b), that partially extends into the other rotor section so as to terminate in the other rotor section; and d) inserting a locking member, after step c), into the first locking cavity such that the locking member is located partially in both the first locking cavity and second locking cavity to form a locking system to maintain the primary joining system, and wherein b) includes forming and disassembling the primary join at least two times before the final join is made.