FIELD: mining.
SUBSTANCE: group of inventions relates to systems and methods for drilling with casing string. Invention discloses system and circulation rate control method of underground drilling fluid and pressure using wall passage through underground formations for drilling mud injection to locate device and for extension of passage through underground formations. System comprises casing containing at least one device for passage of drilling fluid and casing string containing first casing string and at least one additional casing string of larger diameter, wherein first column of casing pipes includes channel passing longitudinally through proximal area of passage through underground formations and forms internal passage through the channel, at least one additional column of casing pipes of larger diameter extending longitudinally through proximal area of passage through underground formations and extends in axial direction downwards from the external protective casing string, coating proximal area, thus forming first circular passage between its wall and surrounding wall of underground passage. First column of casing pipes passes at least partially inside first end and second end of at least one additional casing string of larger diameter to make intermediate of inner passage, at least one additional circular passage or combinations thereof, wherein at least one device for passage of drilling mud connects first casing string with at least one additional casing string of larger diameter and contains at least one radial passage passing between internal passage, intermediate internal passage, at least one additional annular passage, first annular passage or combinations thereof so that drilling mud, passing in at least one passage, is diverted through at least one radial passage to other passage in order to use, to control speed and pressure circulation underground drilling mud for placement of device or for extension of passage through underground formations.
EFFECT: technical result is higher efficiency of device due to selective control of speeds of circulating fluids or fluids flow.
27 cl, 166 dwg
