Limit moment of local wall thinning in pipe under bending

In engineering practice, pipe containing local wall thinning may be subject ed to bending load. The existence of local wall thinning on pipe surface im pairs the load-carrying capacity of pipe. In order to maintain the integrit y of the pipe containing local wall thinning, it is very important to devel op a method to evaluate such a pipe with local wall thinning under bending. In this paper, the limit moment of local wall thinning pipe under pure ben ding is computed employing 3D elastic-plastic finite element analysis. The results show that the limit moment of pipe is affected not only by the widt h of defect but also by the longitudinal length of defect. When the longitu dinal length of defect overpasses some critical value, the results from net -section collapse criterion (NSC) are in very reasonable agreement with the results from finite element analysis. Therefore, the NSC formula can conse rvatively be used to assess the limit load-carrying capability of local wal l thinning pipe under bending. (C) 1999 Elsevier Science Ltd. All rights re served.