BOSS DESIGN OF ALUMINUM LINER FOR FILAMENT-WOUND COMPOSITE PRESSURE VESSEL CONSIDERING WEIGHT REDUCTION

摘要

Filament-wound composite pressure vessels are widely used in aerospace field because of the excellent specific strength of composite materials. Since the recent trend is that composite material takes exclusive responsibility of internal pressure loading, the elongation of liner should be high as much as possible in order to accommodate the deformation of composite material and to maintain air tightness. However, the better the elongation is, the lower the thread strength of boss fitting becomes. In the current study, design for improving the strength of boss with high elongation has been carried out. The determined configuration is a boss that has the separable flange with tap, and the flange is fastened to boss by several tension bolts. The size and quantity of fastening bolt were determined throughout theoretical calculation. After that the feasibility of the design was investigated by finite element analysis and pressure loading test after winding composite. It showed a reasonable result and considerable weight reduction compared with the existing design.