大容量钴源运输容器屏蔽研究

大容量钴源运输容器为运输工业用钴源而设计的专用设备。由于内容物放射性活度水平很高、衰变热很大,仅有少数国家具有设计能力,在国内的研制尚属首次。在对钴源运输容器的屏蔽设计研制过程中,突破之前的屏蔽设计技术束缚,采用MCAM程序与MCNP程序模拟计算钴源运输容器外的剂量率水平,并在设计过程中及时发现容器存在的设计缺陷,从而进行了设计改进,保证了容器满足国家标准要求的各项设计措施。目前这些设计措施已通过相关的试验验证。结果表明:针对大容量60 Co运输容器的关键技术制定的设计措施合理有效,充分保证了容器在经受国家标准中规定的正常运输条件和运输中事故条件下各项试验后容器屏蔽性能的完整性,确保钴源运输的安全。

Research on Shielding of High-capacity Cobalt Source Transport Cask

High-capacity cobalt source transport casks are used to transport ⁶⁰Co industrial irradiators. The radioactive contents have special features of high-activity and high residual heat, so only a few countries have design capacity. This is the first design project for the self-reliant design of high-capacity cobalt source transport casks. This paper was devoted to key technology in shielding design of these casks. The MCAM code and MCNP code were used for the calculation of the dose rate level outside the cask and the design -improvement was applied in the cask to meet the requirements in national standard. A series of test proved the casks have ability to transport high-activity sealed sources safely. Calculation results in design are in well concordance with survey results. It demonstrates the rationality and reliability of the methods used in this shielding design. The patent for the design of high-capacity cobalt source transport casks was obtained. Through the design for cobalt source transport casks, a good foundation is laid for the self-reliant design of spent fuel transport cask.