ABOUT THE NATURAL BOUNDARY CONDITIONS ON A BORE BIT FOR SOLUTION OF THE GENERAL STABILITY PROBLEM OF THE DRILL STRING

Abstract

The common task of stability of a drill column is considered. The axled forces, torque are taken into account, the losses of stress on a chisel, in a tube and external casing space are divided on length of gain from operation of inner and  expansion barrel flush fluid, slugged load from turnaround of arranging by a curl. The top end of arranging is accepted gimballing supported, and for lower (on a chisel), using variation production of the task, the natural boundary conditions are formulated. Influencing major factors on critical values of axled force and angular velocities turnaround of a curl for three standard arranging and also influencing of design features of the updated cone rock bit on critical values of thrust loads is rated.