The effects of welding residual stress (WRS) would be harmful to safety and intensity of pressure vessel. X-ray stress analyzer (XRSA) can be used to non-destructively quantitative analyze WRS. In this study, stress changes of constant stress beam in loading process were tested using strain gauge (SG), strain rosette (SR) and XRSA, and their test results were compared to analyze measurement errors of XRSA. It was found that the property of XRSA meets the experimental requirement. The machining stress in surface of welding test plate could be completely removed after 4 min electrolytic polishing under 1 A current and 100% NaCl electrolyte. The WRS of welding test plate was tested by XRSA after machining stress completely removed, and its distribution along vertical welding seam direction corresponded with theory calculation. Furthermore, XRSA as a non-destructive method will be more used to study WRS of pressure vessel, so these results can provide scientific basis for the studying.

Welding residual stress (WRS) has been paid more attention because it would be harmful to safety and intensity of spherical tank. X-ray stress analyzer (XRSA) can be used to non-destructively quantitative analyze WRS. In this study, the real values of Young’s module (E) and Poisson’s ratio (ν) of materials were used to quantitatively calculate. The initial θ0 of materials of welding seam, heat-affected zone and base metal (16MnDR) with zero-stress were detected to analyze influence of quantitative calculation. Moreover, ±5° ψ-oscillation was chosen to use in testing process by XRSA to decrease dispersion of testing data due to large grain size in welding seam and heat-affected zone. Furthermore, XRSA as a non-destructive method will be more used to study WRS of spherical tank, so these results can provide scientific basis for the studying.