Modeling of the Turbine Rotor Journal Restoration on Horizontal Balancing Machines

Abstract

During the normal operational life of a turbine, its rotor journal seating surfaces are wearing and therefore, repair operations, including turning and grinding of such surfaces and next rotor balancing on the balancing machines, are carried out. Traditional turbine rotors machining is provided by fixing them through the centers and demands the corresponding large size machine tools and the strategy «machine tool to rotor» is often used. To minimize mobilization and transportation cost, the problem of the turbine rotor restoration by using centerless grinding technique on the lightweight horizontal balancing machines is resolved. A computer simulation model of such grinding with workpieces located on their machining surfaces is presented. To validate the approaches, a proposed computer simulation was carried out. Theoretical and computational investigations demonstrate that the deviation from the roundness of a workpiece may be reduced from the initial value of half a millimeter to a final value of 10 micrometers by using a special location of cutting tools.