METHOD FOR REDUCTION OF TORSION TORQUES OF DRILLING RIG AT STAGES OF PRELIMINARY WELL EXPANSION AND IN PROCESS OF WELL PREPARATION OF PIPELINE DRAGGING

摘要

FIELD: construction. ^ SUBSTANCE: method for reduction of drilling rig torsion torques at stages of preliminary well expansion in process of well preparation for pipeline dragging in it includes drilling pilot well and its expansion prior to pipeline dragging. At the same time expansion is carried out in stages by means of expanders pulling-through, and well cross section is shaped close to ellipse, with arrangement of its largest diametre in vertical plane, area of cut soil is reduced in single passing of expander in well by repeated pulling of expander in well without increasing expander diametre. ^ EFFECT: reduced energy intensity of process with reduction of torsion torque. ^ 4 dwg