目的 国内首批制造的乏燃料运输容器已到寿期，而此前国内没有对该类容器进行延寿审批的先例，为确保延寿的容器仍满足法规标准要求，给出了研究乏燃料运输容器延寿的评价方法和实例。方法 容器设计寿命延长评价分为针对该型号容器的评价和针对每台容器的评价，上述2方面均满足要求时，证明延寿的容器能保证安全。结果 经试验和评价，此批容器满足要求，容器寿命延长安全可行。另外，为本次容器延寿设计了力学试验，并对此进行理论分析，分析结果与试验结果相吻合。结论 提供了行之有效的对小型乏燃料运输容器进行延寿评价的方法，以本研究提供的方法为主线，加上对大型容器特有功能材料和重要结构的寿命评价，可为大型商用核电站乏燃料运输容器延寿评价提供重要参考。

The first batch of spent reactor fuel transport casks manufactured in China have reached their life span, and there is no precedent of life extension approval for this type of cask in China before. Therefore, in order to ensure that the containers with extended life still meet the requirements of laws and standards, the work aims to give the evaluation method and example of studying the life extension of spent reactor fuel transport casks. The evaluation of design life extension was divided into the evaluation for this type of cask and the evaluation for each cask. The evaluation results met the requirements in both aspects, which proved that the cask with extended life was safe and feasible. Through the test and evaluation, this batch of cask met the requirements, and the life extension of the cask was safe and feasible. In addition, a mechanical test was designed for the life extension of the cask, and the theoretical analysis was carried out, of which the results were consistent with the test results. An effective method is proposed to evaluate the life extension of small spent fuel transport cask. With the method provided in this study as the main line, together with the life evaluation of special functional materials and important structures of large casks, it can provide important reference for the life extension evaluation of spent fuel transport casks in large commercial nuclear power plants.