Generally for the piping, you have to consider the pipe elasticity being changed by the ambient tempature or the imperative temperature difference. Vibration that would ineviably be generated upon starting the machine shall also be considered. The body of the ship can be bent horizontally or vertically by surges. The elastic convex type expansion joint would be the most appropriated one to tolerate pipes shirinkage, expansion, impact, earth quake and twisted misalignment.