METHOD FOR WELL WITH REMOTE BOTTOM CONSTRUCTION Russian patent published in 2008 - IPC E21B7/04 

FIELD: well drilling, particularly to drill inclined, near-horizontal and horizontal wells having bottoms spaced tens of kilometers therefrom and located under water conservation zone, river or shelf water.

SUBSTANCE: method involves forming prospect-hole spaced admissible distance from shore line; installing curvilinear part of horizontal conductor in design azimuth in prospect-hole; drilling horizontal well bore from prospect-hole by trench or thenchless method so that the horizontal well bore is located near ground surface and/or water area bottom; pulling through or laying welded large-diameter pipe strings into horizontal well bore to provide horizontal conductor, wherein the pipe string terminates in end curved downwards through zenith angle and used as additional pipeline for produced liquid and/or gaseous hydrocarbon transportation. Well is drilled from under horizontal conductor bottom with the use of drilling string assembly. Drilling string is installed in horizontal conductor and includes initial drilling string section, central one and terminal one. Initial and central drilling string sections are rigidly connected with each other and include central pipe coaxial relatively inner pipe. Central section additionally has outer pipe. End section comprises inner pipe and mud pipe telescopically connected with outer pipe of central section. Hole annuity defined by mud pipe of end section and horizontal conductor, outer pipe of central section and horizontal conductor and central pipe of initial section and horizontal conductor, is filled with liquid having predetermined density. Hole annuity between central and outer pipes of central sections is filled with air or gas. Drilling string assembly is prepared at well head from drilling rig in the following order: rock-cutting tool, bottomhole drive, telemetering system, end, central and initial drilling string assembly sections.

EFFECT: possibility to create horizontal well bore of maximal possible length in rock having any strength, including unstable and liable to keyseating and caving one due to minimized load necessary to overcome drilling string movement resistance force.

5 dwg