METHOD OF DRILLING THE DIRECTIONAL AND HORIZONTAL PROSPECTING OR PRODUCING WELL FROM OIL AND GAS Russian patent published in 2000 - IPC

FIELD: drilling of directional and horizontal wells. SUBSTANCE: essence of invention consists in that on sections of trajectory of formation and stage casing of directional and horizontal wellbores, created and maintained in wellbore are conditions of partial or full weightlessness of pipe string by regulation of reduced density of pipe string components and holding drill hydrosphere circulating in well. EFFECT: higher efficiency of drilling of directional and horizontal branches from main wellbore. 2 cl, 7 dwg