Hot-tube spinning process for manufacturing ultra-high pressure vessels (Type-I): process planning and implementation

This study investigates the advanced fabrication of Type-I ultra-high pressure vessels via the hot-tube spinning process, unveiling previously undocumented deformation mechanisms critical to the creation of seamless vessels with significant wall thicknesses, exemplified by a 64 mm gauge. In compliance with the criteria of ASME SEC VIII Div. 1 and Div. 3, the research calculates the minimal wall thickness required for these vessels to endure a hydrogen pressure of 99 MPa. Finite element analysis is employed to analyze stress distributions, thus enhancing the understanding of the vessels’ structural integrity. Simulations executed with Forge NxT software reveal distinct material behaviors, including build-up phenomena and the non-uniform curvature of the dome section. These findings are validated by experimental trials, indicating a strong alignment with the theoretical models. The objective of the research is to integrate simulation and real-world production, facilitating comprehensive investigations into how manufacturing parameters influence vessel formation and the occurrence of defects. Discrepancies in wall thickness between simulated and actual test results are confined within a 10% margin of error, verifying the operational safety of the vessels at the critical pressure limit.