Dynamic properties of a drill-pipe string
The idea of a drill casing string as a two-mass model with the assumption that one mass is concentrated at the well head and the other one in its bottom area and the dynamic load increase as a parameter to control the drilling process is substantiated. Estimation of dynamic stability of a drill casing string, beforehand thought as unstable, is performed on the basis of transfer functions of the structural model. Theoretical provisions about dynamic behavior of a drill casing string in the process of a well’s deepening is experimentally confirmed.