FEM Stress Analysis of Tee Intersections With LTA

Abstract

In this work a three-dimensional finite element study is carried out of pressurized piping tee (tee) intersections, with local area wall thinning (LTA). Two types of stress analysis are carried out, dealing respectively with the determination of the stress concentration factor (SCF), and of the plastic collapse load. Stress values determined for vessels with uniform thickness are compared with previously published work. An evaluation is then made of the effect on the SCF values of varying the size and shape of the LTA around the intersection. This is followed by a parametric study in which the SCF and the collapse load are computed for intersections with different depths of wall thinning. Finally, comments are made on the fatigue of tees with LTA having cyclical loading superimposed on the constant pressure loading.

Junctions in shell structures: A review

“…It was found that the total stress value under the combined loads was not completely equal to the total value gotten by adding the two stress states under separate loads. Ahmad et al [179] carried out a 3D FE study on stress analysis in pressurized piping tee intersections. Then the stress concentration factor and the plastic collapse load were found for intersections with different depths of wall thinning.…”