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，延长老化资产的运营寿命往往比进入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较长的运行寿命。基础设施老化过程的安全和成本效益管理需要稳健的初始系统设计，以及实施集中的维护制度，该制度可以动态调整，以满足整个运行过程中不断变化的系统需求。控制风险的第三种选择是在发生失控事故时设立宽限期。在此期间，恢复关键系统功能的可能性很高。安全关键系统、设计和维护选项将侧重于防止发生无法控制的危险事件。宽限期的产生将提供一个机会，使反应堆安全，即使在事故序列已经进展。通过描述的三个特征，该项目将调查最具成本效益的方式，为反应堆生产安全和可靠的寿命延长。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。对于设计固定的当前反应堆，系统状态将通过有效使用维护来控制。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，维修将包括：维修、测试/检查、反应性维修、因使用、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，可以考虑全面的防御方案，期望延长运行寿命，使之比目前的设计寿命规范更长。通过将建模方法嵌入决策支持框架，将考虑不同的风险防御方案，以产生安全可靠的核电站性能的成本效益选择。所产生的方法将通过对反应堆系统的应用进行验证。

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.