The proposed experiments aim to investigate residual stress genesis in a Ni alloy 600/82 multi-pass weldment simulating a repair weld and residual stresses redistribution after removing of the overflowed weld at the surface by grinding process. The grinding process was carried out on a sample produced with the same welding process and similar parameters. These types of weld repair and surface finishing are widely used in welded components in pressurized water reactors fission reactors (PWRs).The results obtained on specific specimens with the different diffraction techniques will also be compared with contour method and thermo-mechanical process computational models predicting RS to have a characterization of the multi-technique and multi-scale residual stresses.