Reliability of the piping systems of a modern submarine

It is a common knowledge that safety is of importance for every sailing vessel but becomes unquestionable for a submarine for obvious reasons. Prerequisite for the safety of a submarine is that all its structural parts “working” on the diving pressure when the submarine is underneath, can withstand successfully the exercised enormous pressure and consequently the developed high stresses imposed on them. Piping of the submarine is one major part under diving pressure. The best way to assure these prerequisites, is to inspect piping frequently and using destructive and non destructive methods to get the necessary level of assurance or confirmation of safety. This is not always an easy task particularly in a submarine where the space is very “crowdy” and the major part of the piping is practically inaccessible. Therefore, a more rational way has to be established, a way that would allow verifying the condition of inaccessible parts by making certain that piping retains the necessary reliability that allows the submarine to be further safely used. This is the scope of the present study namely by using a “rational approach” to assess accurately and objectively the reliability of the piping. Having achieved that, one can proceed further and determine the probability of a certain deterioration for a specific time frame and/or the time frame in which you anticipate the deterioration of a piping to exceed a predetermined “threshold”. Last but not least, in the development of this study the accuracy of the mathematical models used have been compared to actual measurements (data) taken in a later stage. Very much to our satisfaction all these comparisons turned to be very close in a surprisingly matching way. This coincidence holds promise for further and more extensive applicability of the models used.