MECHANICAL BEHAVIOR OF DRILLSTRINGS IN CURVED BOREHOLES WITH LOCAL GEOMETRICAL IMPERFECTIONS

摘要

The problem of elastic bending of drillstrings in deep curved boreholes with geometrically imperfect axial lines is stated based on the theory of curved flexible bars. The dependence of the force resisting the motion of the drillstring on the amplitude, spacing, and location of geometric imperfections is analyzed numerically. The numerical results are discussed