Production process of aluminum alloy tank of SPB LNG carrier

New type of LNG carrier with independent aluminum tanks of prismatic shape, SPB system (Self-supporting Prismatic Tank Type-B System), was developed in Ishikawajima-Harima Heavy Industries, Co., Ltd. (IHI). This system is specialized by the accurate estimation and guarantee of fatigue strength of aluminum tanks, hence, the stress concentration around welding bead has to be controlled under the allowable value. Though many reports have been made already, especially for design and analytic technologies, and also welding technologies to accomplish this system, practical application concerning the production process has not been reported yet in detail. This paper introduces the technology development on production process for the aluminum LNG tank.