Integrated finite element simulation and experiment verification of the large-sized straight welded pipe processing with JCOE technology

摘要

The integrated and continuous finite element simulations ot the JCOE forming technology (progressive forming process of 'J' forming, 'C forming and 'O' forming, reducing gap, welding and mechanical expanding) for large-sized straight welded pipe are implemented based on the MARC software. The simulation results of the JCO continuous model and simplified as ellipse model are compared with the production results, which indicates that the section contour and sticking state between the expander die and inner wall of the tube for continuous model are more close to the production results. The area in the suspended zone is in the tensile bending deformation state and the residual stress in the suspended zone is mainly concentrated in the outer layer. Taking the relative expander die radius (the ratio of expander die radius and the inner radius of finished welded pipe) and expanding ratio as variables, the expanding process of the JCO continuous model is simulated. The results indicate that, when the relative expander die radius is 1.05, the deformation of the pipe is uniform and the larger of the expanding ratio, the lower the residual stress when the expanding ratio is in the range 0.8-1.7.