HEAD DRILLING STRING DRIVE Russian patent published in 2006 - IPC E21B3/00 E21B19/00 

FIELD: mining, particularly head drives for deviating well drilling.

SUBSTANCE: head drive comprises swivel, rotary unit with planetary reduction gear, electric motor with hollow shaft, suspension system for block-and-tackle unit and pipe string. The swivel and rotary unit mechanisms are built in block-and-tackle unit body. The block-and-tackle unit has two sets of pulleys with two-directional pulling ability.

EFFECT: reduced metal consumption, reduced height and possibility to drill deviating wells due to creation of pulling force in both drilling string movement directions, possibility of forcedly pipe string driving in wells, possibility to drill deviating and horizontal wells at low depths due to increased axial force, possibility to flush well at any time regardless of upper drilling string end location.

2 dwg