FINITE ELEMENT MODELING AND EXPERIMENTAL STUDY OF RESIDUAL STRESSES IN REPAIR BUTT WELD OF ST-37 PLATES

Welding is one of the most important assembling methods which are widely applied in different applications. In service conditions, some of the weld joints which meet defects must be repaired. The residual stresses impress the operation and efficiency of the repair weldment. In this study, the temperature and the residual stress fields were investigated by both the finite element simulation and the experimental measurement due to repair butt weld of the two thin St 37 plates. The welding process was simulated using the three-dimensional finite element and the Goldak double-ellipsoid heat source models. The temperature distribution and the residual stresses were computed both in the initial and repair welds. The element birth and death technique was used to simulate the filler metal deposition into the weld pool. The experimental measurements were performed to verify the numerical results in the both initial and repair welds. The residual stresses were measured using the hole drilling method. The experimental results revealed that the finite element simulations obtained in the present work were capable of predicting the residual stresses in the initial and repair welds. Also, the effect of the repair length variation on both magnitudes and distribution of the transverse and longitudinal residual stresses were shown.