基于裂纹失效路径的压力容器剩余寿命预测新方法

裂纹的扩展行为研究是压力容器剩余寿命预测的关键与基础。针对目前难以准确预测压力容器表面裂纹剩余寿命的状况,通过建立压力容器表面裂纹的受力模型,利用有限元方法分别计算出裂纹表面点与最深点处的应力强度因子,得到裂纹深度a与长度c的变化之比,运用压力容器仿真系统进行路径仿真与失效速率仿真,得到裂纹在安全区域的临界拐点及临界值aN。实例计算结果表明,表面裂纹的失效路径能够直观准确的表示裂纹的扩展规律,进行有效的剩余寿命预测。

New Method of Residual Life Prediction for Pressure Vessel Surface Crack Defects Based on the Crack Failure Path

Crack propagation is the key and foundation of pressure vessel residual life prediction. It is difficult to accurately predict the status of the pressure vessel surface crack residual life. In order to solve this problem ,By establish the stress of pressure vessel surface crack mode and respectively using the finite element method to calculate the crack stress intensity factor of the surface points and the deepest point, In the end we are simulated on the propagation of the pressure vessel surface crack. Experimental results show that crack law failure paths can accurately reflect the propagation of the crack.