DRILLING TECHNIQUE AND GEAR FOR REALIZATION OF TECHNIQUE Russian patent published in 2003 - IPC

FIELD: drilling of holes of various assignment with use of downhole hydraulic machines of percussion action-hydraulic hammers. SUBSTANCE: proposed technique includes transmission of axial loads on rock-breaking tool anchored on double drilling stem, formation of gas-and-fluid mixture, cleaning of face with it and transportation of cuttings. In case of employment of hydraulic hammers gas-and-fluid mixture is formed directly in face zone by way of separate supply of compressed air and liquid working substance over tubular and central conduits of double drilling stem and their mixing in face zone above rock-breaking tool. Gear for realization of technique has double drilling stem with tubular and central conduits, hydraulic hammer with working chamber housing valve and space for interaction of spring-loaded piston-bullet with anvil, rock-breaking tool, pump. Space for interaction of spring-loaded piston-bullet with anvil of hydraulic hammer communicates through radial holes in internal pipe with source of compressed air over one of conduits of double drilling stem, working chamber of hydraulic hammer communicates with pump over another conduit of double drilling stem. EFFECT: enhanced drilling efficiency. 2 cl, 2 dwg