METHOD OF CORK DESTRUCTION IN WELL Russian patent published in 2020 - IPC E21B37/00 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil and gas industry, namely, to plugs destruction during repair of oil and injection wells. Proposed method comprises lowering of tubing string to tubing string to roof of sand plug, injection of flushing fluid to the well, destruction and flushing out of sand plug, removal of flushing pipe string from well. Before lowering, the flushing pipe string is equipped from below with a destructive tool made with possibility of rotation and destruction of the plug. Wellhead is used to communicate with annular space between the tubing string and the flushing pipe string for injecting flushing fluid during back flushing of the well or its spill in washing the plug substance during direct flushing. Cross-sectional area of the flushing pipe column at back flushing and / or annular space during back flushing is selected proceeding from the rate of upward flow of flushing liquid, which must be higher than the rate of sedimentation of the substance of which the plug consists. For direct flushing dimensions of annular space are selected not less than critical for deposition on walls of substance, of which plug consists. Direct and back flushing of the well can alternate depending on efficiency of plug substance washing-out.

EFFECT: enlarging functional capabilities due to cleaning of the well from the plug with large thickness and / or pressed, excluding the possibility of contamination with the flushing fluid washed out space between the production string and the flushing pipe string, increased efficiency of well cleaning, if necessary, by reverse movement of flushing fluid.

3 cl