Introduction  Sealing of reactor pressure vessel is one of the key factors in the safe operation of nuclear power plants, and therefore it has significant importance in engineering to conduct the in-depth study of its contacting systems. Based on the application characteristics of finite element analysis, we have developed independently a software ATLAS, where a lot of innovation optimizations have been done in terms of pre-sorted file caching and 3D rendering technologies that allows CAE engineers working in highly interactive and visual environments.

  Method  In this paper we used ATLAS to create a pressure vessel model, and then simulated numerically the contacting and the sealing of pressure vessel, and finally obtained the mechanical characteristics and stress distribution, and evaluated the strength and fatigue analysis of its critical section.

  Results  The results show that ATLAS can accurately import and mesh models, apply a variety of conditions, quickly complete finite element analy ele sis of contact problems. The accuracy of the results can be guaranteed, according to the methods, the designed flange meets the requirements of structural strength and durability.

  Conclusion  As a rapid finite element analysis system for large-scale structures, ATLAS provides tools for structural sealing analysis and strength checking for reactor pressure vessel and it has good application prospects.