METHOD OF DRILLING WELLS IN CONTINENTAL ICE Russian patent published in 2023 - IPC E21B7/18 

FIELD: oil and gas.

SUBSTANCE: invention relates to drilling wells in the continental ice of Antarctica using a combined method using a high-pressure liquid jet and cutting elements of a rotating hydraulic jet head with cleaning of the entire wellbore from slurry with a non-freezing flushing liquid. A method for drilling wells in continental ice includes installing a casing string in firn, filling the casing string with dimethylpolysiloxane liquid, running in a high-pressure hydraulic pump with a rotating cutting hydrojet head into the well, installing it at a distance of 3 to 10 mm from the bottom and cleaning the dimethylpolysiloxane liquid from sludge using slurry pump and separator. The operating pressure of the dimethylpolysiloxane fluid is created using a drilling pump on the surface in the range from 5 MPa to 20 MPa, which is transmitted through flexible continuous pipes with a built-in electric cable to the drilling rig, in which it is increased to a value from 35 MPa to 50 MPa by a high-pressure hydraulic pump with an electric drive. A high-pressure flow of working fluid is directed into a hydraulic jet head with built-in steel cutting elements, which is rotated by a hydraulic downhole motor, and at the same time the drill string is lowered to the bottom using flexible continuous pipes. The ice at the bottom of the well is destroyed with the formation of a cylindrical shape of the well under the combined influence of high-speed jets of working fluid and mechanical cutting of ice. The reaction torque from the operation of the drill at the bottom of the well is reduced by multidirectional rotation of the high-pressure hydraulic pump with electric drive and the downhole hydraulic motor. The flow of working fluid emerging from the drill string is used to transport cuttings from the bottom to the wellhead.

EFFECT: improved efficiency of the process of drilling deep wells in continental ice.

1 cl, 3 dwg