Simulation on Stress Distribution of Drill Pipe’s Surface Initial Crack

Abstract

Abstract: In drilling process, drill pipes’ out surface always have lots of pits and scratches due to the corrosive and erosion of mud or wear of well wall in work environment. Through establishing drill pipe’s working model and constitutive equations with Finite Element Analysis Software, the paper have simulated stress distribution on drill pipe body under two different condition that without mechanical damage and with initial crack. Analysis results show that the maximum stress increases with the increasing of initial crack depth, and the maximum stress position turns to crack circumferential root from the crack radial root with the increasing of initial crack’s depth. The analysis result is completely consistent with the actual morphology of crack propagation, as a result, the simulation analysis provides a effective new methods and reference for remaining life assessment and failure analysis of drill pipe.