Influence of crack shapes on crack propagation life of sucker rods in the corrosive environments
LENG Jiancheng
YUE Jianghong
ZHANG Xin
XU Hongwei
Abstract：[Objective]To clarify the influence of different initial crack shapes on the fatigue life of sucker rods,crack propagation simulation and residual useful life(RUL)prediction were conducted on sucker rods in corrosive environments using FRANC3D fracture mechanics software.[Methods]Firstly,the simulation accuracy of the M-integral method for calculating stress intensity factors was verified by comparing with the Newman-Raju solution.Secondly,a finite element model of in-service sucker rods was established based on Ansys WorkBench software and simulation analysis was conducted.The maximum von Mises stress was found at the intersection of the cutting groove and the shoulder.Finally,the secondary development of FRANC3D software was carried out based on the Python interface,and crack propagation simulations were conducted respectively on semi-elliptical and long-shallow surface cracks in non-corrosive and corrosive environments.[Results]The results show that both types of cracks propagate rapidly from the middle to both ends initially.When the crack extends to a certain depth,the front edge of the crack gradually becomes elliptical,reducing its impact on the subsequent crack propagation rate.The RUL under corrosive conditions is reduced by 28.95%and 28.32%,respectively,compared to non-corrosive conditions.This study provides reference for predicting the residual life of in-service sucker rods.
Keywords：Fracture mechanicsCrack propagationCrack shapeResidual useful lifeSucker rod
Publication Date：2026-01-31
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：7( 56-62 )