Fitness-for-Service Assessment for Steam Generator Tube Fretting at Darlington Nuclear Generating Station

Abstract

Ontario Power Generation (OPG) has developed and implemented a systematic managed process for steam generators at all of its facilities. One of the key requirements of this managed process is to have in place long range Steam Generator Life Cycle Management (SG LCM) plans for each of its reactor units. The primary goal of these plans is to maximize the value of the nuclear facility through safe and reliable steam generator operation over the expected life of the units. These SG LCM plans integrate and schedule all steam generator actions such as inspection, operation, maintenance, repairs, modifications, assessments, performance monitoring, research and development, and feedback. This paper provides an overview of how structural and leak-rate testing, being conducted by OPG, is being used to support fitness-for-service assessments for fretting degradation in the U-bend region of the recirculating steam generators at the Darlington Nuclear Generating Station.