Axis shift distortion is one type of distortion encountered during the circumferential welding of large, thin pipes. The result of this is the loss of coaxiality of the pipes. This type of distortion is caused by the time lag in the solidification of various segments of weld metal around the circumference. The development of shrinkage forces in the weld metal especially in the axial direction is nonuniform due to the time lag, and this causes axis shift for the pipes. The development of a mathematical model using the finite element method for prediction of axis shift distortion in thin pipes is described in this work. Thermal analysis and subsequent elastic-plastic stress analysis for the pipe are performed using four-noded, bilinear degenerated shell elements. In addition to axis shift distortion, axial and circumferential stress distributions in the pipe are also determined by the model. The model is validated by conducting partial welding on the circumference of a thin pipe and measuring the transient thermal history and root opening at the bottom. Details of thermal and elastic-plastic analyses, welding trials, thermal and displacement results and axial and circumferential stress results are presented in this paper.