PROCEDURE FOR ABANDONMENT OF WELL WITH MULTITUDE OF INTERVALS OF LEAKAGE OF PRODUCTION STRING Russian patent published in 2011 - IPC E21B33/13 

FIELD: gas and oil production.

SUBSTANCE: invention refers to abandonment of operational, exploratory and prospecting holes with multitude of intervals with production string leakage in out-of-the way places in zone of permafrost rock (PFR). At implementation of the procedure the well is killed, a production tree is disassembled to a case of a pipe head whereon there is installed blowout preventer equipment (BPE). The production string is extracted from a hole. Washing pipes are lowered to bottomhole. Cement grout in volume sufficient for filling borehole of well is pumped. Simultaneously washing pipes are lifted along borehole of the well to the wellhead and are extracted from the well. Upon completion of a period of waiting for cement hardening the BPE is dismantled, a transfer reel and central gate are mounted in its place, internal cavities of string and pipe heads and also of a central gate are filled with cement grout; all side branches and an upper flange of the central gate are sealed with blind flanges and a bench mark is set.

EFFECT: raised reliability and ecological safety of gas-oil well abandonment at minimal capital expenditures.

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