Analysis of Fatigue Life of Thick-Wall Cylinder with Inner Surface Crack Subjected to High Pressure

Based on the basic formulation of K_I and using Schmitt-Keim coefficient and considering the effects of the pressure medium,the K_I of two thick-wall simulated tubes with initial cracks had been calcu-lated and the calculative results were agreed with the tests.The Paris equation was used as the model of crack growth rate and its coefficients were given in this paper.The fatigue lives of the thick-wall simulated tubes were calculated and the relative curves of fatigue life with pressure were obtained.For generality,the formulations for conservative calculations of the fatigue life of thick-wall tube with inner surface crack were pro-posed and can be used to estimate the fatigue life of thick-wall tube.