DEVICE FOR SIMULTANEOUS DRILLING AND FIXING OF WELL TROUBLE ZONES Russian patent published in 2024 - IPC E21B7/20 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil and gas industry, namely to drilling of oil and gas wells with simultaneous isolation of caving and landslide zones during drilling of expandable pipes with a string. Device for simultaneous drilling and fixation of well trouble zones includes a removable expandable bit, expandable casing pipes are lowered with possibility of disconnection from the drill string on a landing sub equipped with a bore with a cone for narrowing of the cylindrical end of the upper casing pipe and keys. Expanding bit is connected to the body of the connecting unit by means of an expandable bit adapter, and the connecting unit holder is rigidly connected to the lower end of the casing pipes with the possibility of disconnection and removal of the connecting unit body from its holder at axial downward movement of the plunger with a groove, into which the connecting unit dies move radially to the centre. Expandable tubes are cylindrical. Keys of the setting sub are made in the form of movable dies installed with the possibility of movement and fixation in the transport position when the setting sub is disconnected from the casing expandable pipes. Anchor is installed above the connecting unit, which consists of an expandable branch pipe with a shrunk section with sealing elements on the outer surface, and inside the expandable branch pipe there is an expanding cone with a seat for a ball, which is equipped from below with an extraction device equipped with retaining rings for grooves of the connecting unit body. Expanding cone inside above the seat is equipped with grooves for retaining rings of the additional extraction device. Diameter of the expansion cone and the diameter of the connecting unit body are 1-5% less than the inner diameter of the casing expandable pipes.

EFFECT: providing reliability in operation, excluding emergency situations related to the use of shaped pipes – sludging with scale, availability of narrowed transition sections, excluding re-drilling of the well shaft at premature blockage of rock.

1 cl, 4 dwg