PROCEDURE FOR ABANDONMENT OF WELL WITH MULTITUDE OF INTERVALS OF PRODUCTION STRING LEAKAGE IN ZONE OF PERMAFROST ROCK 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 preventor equipment (BPE). A lift string is extracted from the well. Wash pipes are lowered to bottomhole. Cement solution at volume, sufficient for filling annular and tube space of the well, is pumped and pressed into annular space till emergence at a wellhead. Upon completion of a period of waiting for cement hardening (CHW) the BPE is dismantled, cemented in the well wash pipes string is cut off at a level of an upper flange of a tube head case, a transfer reel and central gate are mounted, internal cavities of string, of 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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