Abstract: To solve the problems encountered in the design of the piping system at elevated temperature, the present paper demonstrates a methodology of structural analysis and safety evaluation procedures for high temperature piping. A bridge between piping analysis software and ASME-NH is established. Firstly, the detailed analytical solutions of stress components for piping components (straight pipe and bent pipe or elbow) under multiple loading combinations are proposed. Then, the analytical predictions of the stresses are compared with the solutions given by finite element analysis (FEA). The results show that the proposed analytical results agree with FEA results very well. And finally, the piping structural analysis and integrity assessment procedures are given by coupling the pipe line model and the newly proposed analytical solutions. And thus a method to implement the piping design criteria of ASME-NH-3600 for the analysis of nuclear class 1 piping components is provided.