Abstract
In the present study, fracture tests by hydraulic pressure were performed on corroded and/or artificially flawed colsed-cylindorical-vessels as well as similar new vessels. The results were analized and evaluated by fracture mechanics. Critical pressure for plastic collapse of all the vessels were predicted reasonablly by an equation which assumed a thin thickness with strain hardening material. The results revealed the condition for leak before burst (LBB). Fatigue life of corroded and/or flawed vessels were predicted based on the above results for fatigue crack growth and final plastic collapse evaluated by fracture mechanics. The prediction suggested that corrosion thinning upto half thickness of vessels could be allowed with carefull attention
