Design and Maintenance of Nuclear Safety Systems for Life Extension (DaMSSLE)

对于核电等基础设施密集型行业来说，延长老化资产的使用寿命往往比启动新的建设计划更具成本效益。对于新建造、新设计的反应堆，方法是在整个设计和开发阶段规划一个较长的运行寿命。对基础设施老化过程进行安全和经济有效的管理，需要一个强大的初始系统设计，并实施一个集中的维护制度，在整个运行过程中动态调整以满足不断变化的系统需求。控制风险的第三种选择是，在发生无法控制的事故时，通过制定宽限期。在此期间，恢复关键系统功能的可能性很大。安全关键系统、设计和维护方案将侧重于防止不受控制的危险事件。宽限期的产生将提供一个使反应堆安全的机会，即使在事故序列已经进展的情况下。通过上述三个特点，该项目将研究最具成本效益的方式，为反应堆提供安全可靠的延长寿命。目前老化的核反应堆和处于设计阶段的核反应堆都将被考虑在内。对于设计固定的电流电抗器，将通过维护的有效利用来控制系统状态。维护将在运行寿命的各个阶段有所不同，以应对工厂遇到的不同老化过程。在这种情况下，维护将包括：维修，测试/检查，反应性维修，由于使用，老化或状况而进行的预防性更换以及更新。对于新的反应堆设计，可以考虑全范围的防御选择，期望将运行寿命延长到比当前设计寿命规范更长。通过将建模方法嵌入到决策支持框架中，将考虑不同的风险防御方案，以产生具有成本效益的选择，从而实现安全可靠的工厂性能。所产生的方法将通过应用于反应堆系统来证明。

For infrastructure intensive industries such as nuclear power generation it is frequently more cost effective to extend the operational life of aging assets rather than enter a new build programme. For new build, new design reactors the approach would be to plan for a long operating life throughout the design and development stages.Safe and cost effective management of the infrastructure's aging process requires a robust initial system design together with the implementation of a focussed maintenance regime which dynamically adjusts to address the changing system needs throughout their operation. A third option to control risk is through the generation of a grace period in the event of an uncontrolled accident initiation. During this period there would be a high chance of restoring the critical system functionality.The safety critical systems, design and maintenance options would focus on preventing an uncontrolled hazardous event. The generation of a grace period would provide an opportunity to make the reactor safe even when the accident sequence had progressed.Through the three features described the project will investigate the most cost-effective way to produce safe and reliable life extension for the reactors. Both current aging nuclear reactors and also those in the design phase would be considered. For current reactors where the design is fixed, the system state will be controlled through the effective use of maintenance. The maintenance will vary throughout phases in the operational life-time to respond to the different aging processes encountered on the plant. In this context maintenance will include: servicing, testing/inspection, reactive repairs, preventive replacement due to use, age or condition and also renewal. For new reactor designs the full range of defence options can be considered with the expectation of increasing the operating life for longer than the current design life specification.By embedding the modelling methodology into a decision support framework the different risk defence options will be considered to produce cost effective selections for safe and reliable plant performance.The methodology produced will be demonstrated by application to reactor systems.