METHOD FOR DRILLING VERTICAL WELL BY REACTIVE TURBINE DRILL Russian patent published in 1995 - IPC

FIELD: drilling equipment. SUBSTANCE: when suspended drill rotates in crooked well, it is acted upon by gravity force pressing its body to well lower wall. Drill bit cuts lower wall and drills out bench in it. Then, axial feed from below upward is effected. Such drilling is performed over the crooked well section, and well axis displaces to vertical. This procedure is repeated several times to ensure vertical position of well. After each cutting, axis of crooked well moves to vertical through value equalling the difference between radii of well and drill body. EFFECT: higher efficiency. 1 dwg