An Overview Of Plant Life Management And Life Extension Plan For CANDU? 6

摘要

While commercial versions of CANDU reactors were put into service more than 28 years ago, the first series ofrnCANDU 6 plants (which entered service in the early 1980's) have now reached beyond the middle point of their 30 yearrndesign life. Over the past five years, AECL has been working with CANDU reactor owners to develop and implement arncomprehensive and integrated CANDU Plant Life Management (PLiM) program that will see these plants successfully andrnreliably through to design life and beyond. This program is being applied in three phases planning (assessments andrnrecommendations), life attainment implementation, and extended operation.rnIn-depth life assessments of critical systems, structures, and components (CSSCs) are being carried out. Systematicrnapplications of reliability centred analysis techniques are performed to optimize the performance and effectiveness of systemrnsurveillance, inspection, and maintenance in order to achieve overall reliability enhancements for the plant. Thesernassessments are supported by design, procurement, construction, commissioning, regulatory and operations feedback, as wellrnas an R&D support program focusing on plant aging mechanisms, surveillance methodologies, mitigation methods, andrnimproved inspection technologies.rnConsiderable progress has been made in the development and implementation of the PLiM program. A significantrnportion of the in-depth assessments of critical structures and components and the maintenance optimization studies of therncritical systems required for safe and economic operation of the plant have been completed. Implementation of the optimizedrninspection and maintenance program recommendations that result from these assessments has now begun.rnRecently, two CANDU 6 utilities have initiated the detailed planning of a program for extended operation of thernplant. In performing the phase 1 PLiM assessments, AECL also performed a separate evaluation of extended operation. Thisrntogether with the results of the phase 1 and phase 2 PLiM work will be one of the primary inputs for determining the workrnnecessary for extended operation, and for planning a maintenance program to achieve the utility's targets for safety, reliabilityrnand production capacity during its extended life.rnThe necessary refurbishment required for extended operation will be implemented in a special outage. There is alsornan opportunity to take advantage of the shutdown to perform regular maintenance work; however it is important to ensure thatrnthis work is not unnecessarily deferred to this outage, and adversely influence its schedule or cost.rnAECL is also applying the lessons from the PLiM program to the new CANDU products, to assure future customersrnof safe and reliable operation to longer design lifetimes. Comprehensive life management strategies and plans have beenrndeveloped for these new CANDU products.rnIn this paper an overview and update of the PLiM program, with some recent results and the plant extendedrnoperation activities are provided.