In the present study, the JCO-E manufacturing process, and the structural performance of the fabricated pipe under external pressure has been numerically simulated in a unified approach using advanced finite element tools. The fabrication process has been simulated for a thick-walled line pipe of D/t lower than 20, which is candidate for deep water applications. The effects of forming parameters on the geometric and mechanical properties of the final line pipe have been assessed through an extensive parametric study, and suggestions have been made for optimizing the fabrication process. The finite element results have shown that there is an optimum expansion range corresponding to ultimate resistance of pipe against collapse (maximum collapse capacity) and minimum geometric imperfections of the final product.