Reliability Design And Light Weight Research On The LPG Tanker

This article discussed the domestic and overseas research situation of automobile reliability and lightweight, and analyzed the research theory、methods and achievements on reliability and lightweight at home and abroad. Then combining with the actual project, this paper elaborated the meaning of research on reliability and lightweight for the LPG tanker, and then the specific content and research goals were proposed.Firstly, the paper introduced the main theories involves in this paper, which were fatigue reliability theory、lightweight theory and the theory of fluid and structure interaction (FSI). Combined with the requirements of the enterprise, the general plan to do the research and design of reliability and lightweight for the LPG tanker was introduced.Secondly, after introducing the LPG tanker’s structure, the FEM model of the whole LPG tanker was build, then gained the strength and stiffness information of the tanker. Combind with enterprises’requirement and FEM result, the paper studied the lightweight for the tanker and frame by using high strength steel instead of the normal steel and using size optimization respectively. Then the stress and stiffness of the lightweighted LPG tanker was checked. On the condition that the strength don’t go down, the tanker weight reduced33.3%, and the frame weight reduced8.7%, light weight achievement is obvious.Thirdly, based on the enterprise’s need, fatigue test of the high strength steel welding specimens was done, and got the S-N curve and fatigue limit of the specimens. Then calculated the fatigue life of the original structure, and analyzed the reliability of the new structure with the test data, obtained the fatigue life and fatigue reliability index. Fatigue analysis results showed that the new structure meet design requirements of reliability.Finally, researched and designed the baffle based on the theory of FSI, after analyzed the original structure of baffles, gained the curve of the original structure’s biggest stress and deformation change, and the sloshing condition of LPG. For the shortcoming of the original structure, the paper provided a typical improvement plan, which is successful plan after checking.The results of this study not only solved the lightweight design practical problem of the typical LPG tanker for enterprise, but also can provided a fresh idea and some design analysis data for similar vehicles design and product enterprises, and on the whole, it has good reference value.