Abstract
A lifecycle management program, for turbine balance of plant of light water reactor units which had been operated for more than 20 years but still having a long intended residual life time, was proposed and implemented from the view point of system and equipment supplier. Here would be introduced the program executed for several utilities. The program consists of unit surveillance analyzing both operation and inspection data, degradation assessment for the equipment and prospecting for the future by planning the proper measures for the issues based on both technology and economy. The program is introduced exampling the generating power affected by main steam pressure reduction derived from the scale adhesion and degradation of equipment. Multidisciplinary optimum design for the replacement of the feedwater heaters, one of the items of the planning, is introduced. Additionally would be introduced the new concept maintenance support program, mainly applied to the units already replaced their principal machines and auxiliaries, configured with both the condition based maintenance system monitoring the trend of parameters of a component and the diagnosis of malfunctions ascertaining the equipment by analyzing and synthesizing operation parameters.
