Numerical analysis of thermal stresses in welded joint made of steels x20 and x22

Stress calculation of steam pipeline is presented, focused on the welded joint. Numerical calculation was peiformed using the finite element method to obtain stress distribution in the welded joint made while replacing the valve chamber. Dissimilar materials were used, namely steel 10CrMoV9-10 according to EN 10216-2 for the valve chamber, the rest of steam pipeline was steel X20, whereas the transition piece material was steel X22. Residual stresses were calculated, in addition to design stresses, indicating critical regions and necessity for post-weld heat treatment