摘要 |
FIELD: drilling, particularly deflecting the direction of boreholes. ^ SUBSTANCE: device comprises fastening member connected with drilling string and movable between retracted position, in which fastening member is retracted from well wall, and extended position, in which fastening member projects to well wall to secure drilling string on well wall. Device also has triggering member to move the fastening member between above extended and retracted positions under the pressure of drilling mud present in gap between drilling string and well wall. ^ EFFECT: provision of sufficient axial load applied to drilling bit due to drilling string fastening inside well. ^ 11 cl, 3 dwg |