Finite Element Analysis of Dynamic Fracture Behaviour of Drill Pipe Under Various Impact Loads
Keywords:drill pipe, three-dimensional crack, dynamic fracture, finite element analysis, impact loading
In this paper, finite element analysis is conducted to study dynamic responses of a defected drill pipe (DP) under impact loading encountered in working conditions. Longitudinal impact loading such as tensile, eccentric compressive and torsional impact loading and transverse collision loading are considered. A finite element model is firstly developed and validated, and then employed to evaluate the effects of various impact loading on dynamic responses of the defected DP. It is found that the inertial effect due to tensile impact is the most prominent among all the longitudinal impact loadings. In addition, the effect of the transverse collision between the DP and the borehole wall on the driving force of the crack is evaluated. It is concluded that the dynamic effects of the various impact loading frequently exerting on the DP should be taken into consideration for life prediction of DPs.