Finite element model calculations of primary circuit components containing cracks

Finite element calculations for full-scale experiments on a pressurizer branch pipe model are described. The homogeneous weld on the branch pipe, connecting austenitic materials of pipes 500 and 200 mm i.d. with a crack was tested in the experiment. The weld was modelled by a layer of quadratic pentahedra for which the material properties of the base material were entered. The crack was modelled by non-connection of the networks of the two corresponding volumes. The calculations were performed by using the SYSTUS code and the results were compared with those obtained with the BERSAFE code. The results provided by the two codes are identical in many respects. Comparison of the SYSTUS results with experimentally observed data gave evidence that good results can also be achieved with a relatively coarse network. (J.B.). 1 tab., 8 figs., 2 refs