Two autogenously edge welded beams made from SA508 ferritic steel were investigated with the purpose of validating residual stress modelling tools which are relevant for integrity assessment of structural power plant components. The two specimens were welded with two different torch travel speeds. The residual strain and phase distributions were non-destructively determined by high-energy synchrotron X-ray diffraction. Good agreement between numerical and experimental data was found for the specimen welded at fast speed. Furthermore, the texture changes in the specimen welded at slow speed were analysed by the same experimental technique.