The use of electron beam (EB) welded fabrication for submarine hull valves is an exciting development offering the possibility of low defect, high integrity hull valve design at reduced cost compared with traditional cast valves. Introduction of this technology at the primary watertight boundary requires a very measured approach to ensure that overall survivability of the submarine is maintained. Therefore, the new thinking being stimulated by the possibility of EB fabricated valves must address how these new valve designs will be shock qualified to ensure they are safe and fit for service. If the simple line is taken that each EB welded valve design will require shock testing, then the likely large variation in designs will lead to the situation that every new hull valve variant will require a bespoke in-fluid shock test. Clearly, given the cost of underwater shock testing, this could negate many of the through-life cost savings EB welded valves may offer. In many areas of shock design for submarines, advanced finite element methods are already routinely used where either shock testing is cost prohibitive or technically impractical. These methods provide a potential route whereby valves can be qualified numerically, provided sufficient validation information exists and it is shown that numerical methods can adequately predict the failure modes of a valve under shock. Recent research topics that aim to develop a numerically robust valve modelling methodology are discussed. Some of the key modelling issues such as internal/external fluid modelling, stud fastener integrity and validation are presented.
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