An innovative corrugated rolling process for manufacturing submersible pressure shells with corrugated stiffening structures

As critical structural components in large-scale deep-sea equipment such as submarines and submersibles, cylindrical pressure shells require advanced manufacturing solutions to address the limitations of conventional methods characterized by prolonged production cycles and elevated costs. This study proposes an innovative corrugated rolling process (CRP) for high-performance, efficient fabrication of corrugated pressure shells. The theoretical foundations and critical parameters governing stable CRP operations were systematically established. Through comprehensive finite element simulations, systematic investigations were conducted on material flow patterns during corrugation formation, revealing three distinct processing stages classified into clamping, local forming, and global forming. Analytical results revealed that clamping-induced indentations progressively dissipated during subsequent forming stages. Distinct deformation zones within the billet were identified, consisting of active and passive deformation zones characterized by differential thickness reduction rates that synergistically ensured complete corrugation development. Given the complexity of metal flow in CRP, indicators such as corrugation saturation, uniformity of corrugation height, rib back depression rate, average spread and fishtail coefficient were defined to quantitatively assess the forming quality of corrugated pressure shells. The process rationality and technical feasibility of CRP were verified by the corrugated rolling test. This research establishes a theoretical foundation and provides practical technical guidance for manufacturing load-bearing structural components in large-scale deep-sea applications.