Study on dynamic simulation research of single drill pipe based on finite element method

For making the drilling status of drill-strings more clearly, the single drill pipe in vertical wells is taken as the research object, the dynamic model of single drill pipes in drilling process is established based on the finite element method (FEM). The simulation analysis is carried on for force vibration development of drill pipe considerating the coupling of static force, transverse and torsional vibration. The state of underground drill pipe could be reflected, and provide theoretical basis for the study of MWD control. Analysis of results shows that the stress concentration is prevalent in the threaded and joints department on active-duty drill pipe and the design should be improved. The drilling pressure and speed are important parameters in development process of forced vibration. The dominating participation forms of drill pipe vibration are transverse in shallow wells, and other forms of frequent vibration will be inspired alternately with drilling embed to take combined action, drilling parameters should be adjusted to avoid working on the natural frequencies.