WELLBORE CONSOLIDATING TOOL FOR ROTARY DRILLING APPLICATIONS

摘要

A subpart (430) of a drill string (211) is described having an outer circumferential surface which is contoured and adapted to engage the wall of the borehole with a small angle of attack while exerting during rotary drilling operations an compacting pressure on mud cake and/or cuttings prese nt in the annulus between the drill string and the borehole.