Finite element analysis of thin and thick walled tubular tee joints

In this paper a finite element procedure and the associated computer programs for the analysis of thin and thick walled tubular tee joints under a variety of mechanical and thermal loads are described. The analyses were intended particularly for ASA B16.9 standard tees, used in nuclear power plant piping systems. However, the resulting programs are applicable for a much wider range of tee joint geometries. In order to perform an effective analysis of tee joints by the finite element method, several problems are investigated, including: (1) characteristics of different types of relevant finite elements; (2) procedure for automated generation of finite element data; and (3) the computational efficiency of the computer programs used in the analysis. Descriptions of three computer programs are presented for: (1) stress analysis under arbitrary mechanical load, (2) transient heat flow analysis, and (3) thermal stress analysis for temperature distributions determined from heat flow analysis. Results of typical analyses applicable to both thin as well as thick walled tees are presented. (Auth.)