EARTH BORE DEEP-WATER DRILL RIG Russian patent published in 2012 - IPC E21B7/124 

FIELD: mining.

SUBSTANCE: invention relates to geological survey and production of minerals, particularly, to deep-water drilling. Proposed rill rig comprises structural tank filled with water and communicated with atmosphere to support drill rod with drill crown bit, feed drive including hydraulic control valve and drive of rotation composed of spinner hydraulic motor with inlet communicated with ambient medium via spinner hydraulic motor hydraulic control valve, electrically driven hydraulic pump communicated with pickup of water level in said tank, and throttles. Feed drive is composed of feed reduction gearbox, feed hydraulic motor, feed hydraulic motor hydraulic control valve, toothed rack and pressure gear. Controlled throttles are arranged in parallel and in series with feed hydraulic motor. Spinner hydraulic motor outlet is communicated via its control valve, throttle arranged in series with feed hydraulic motor and its control valve, with aforesaid tank while, via throttle arranged parallel with feed hydraulic motor inlet.

EFFECT: drilling depth independent of hydraulic motor parameters, reduced water flow rate, distributed pressure difference between feed and spinner hydraulic motors.