WELL HORIZONTAL SHAFT DRAINAGE ZONE EXPANSION METHOD BY THE DISTANT SECTIONS ACID TREATMENT WITH THE SIDE CHANNELS DEVELOPMENT Russian patent published in 2019 - IPC E21B7/04 

FIELD: soil or rocks drilling.

SUBSTANCE: invention relates to the field of oil and gas wells offshoots drilling. Horizontal wellbore drainage zone expansion method with the formation distant parts acid treatment with the side channels creation includes the main horizontal and offshoots drilling, the offshoots acid treatment. Before the offshoots drilling at the horizontal well mouth with the open shaft from the bottom up, an arrangement is assembled: a MWD, one drill collar, DC, whipstock, lowering the arrangement on the tubing string, TBG, into the horizontal open shaft so that the whipstock was in the sidetracking interval. Orientation of the whipstock in the direction to the right relative to the wellbore main open horizontal shaft. At the wellhead from the bottom up assembling the arrangement: a milling cutter, a bottomhole motor, BHM, one DC, lowering the arrangement into the tubing string on the coiled tubing, CT. Drilling the kickoff to the right and the offshoot with a length of 10 m drilling at an angle of 2.5° relative to the wellbore open horizontal shaft with a load on the mill of up to 1.0 tons. Stopping the drilling process and raising the arrangement on the CT. Into the tubing string lowering the CT column with a BHM and a chisel at the end and continuing the offshoot drilling to the specified face. After the offshoot face reaching stopping the drilling process and raising the arrangement on the CT from the tubing string. Into the tubing string lowering the CT column with a spherical nozzle at the end to the offshoot drilled face depth and performing the offshoot bottomhole zone acidic treatment by the hydrochloric acid solution injection into the CT column with the CT column simultaneous displacement up to the offshoot kickoff interval. Depending on the offshoots number, repeated the above described technological operations, wherein the wellbore bottomhole offshoots processing pressure zone may be different for each offshoot.

EFFECT: enabling the borehole offshoots development in the right direction relative to the main open horizontal shaft, excluding the offshoot path deviation when drilling downwards, increase in the borehole offshoots acid treatment efficiency and quality.

1 cl, 6 dwg