PACKING WELL KILLING IN THE CASE OF ABNORMALLY LOW RESERVOIR PRESSURE Russian patent published in 2008 - IPC E21B43/12 

FIELD: oil and gas production, particularly killing of gas and gas condensate packing wells provided with packer, circulation valve and other downhole equipment included in production tubing before well overhaul, for instance killing of wells exposing thick production reservoir or several reservoirs simultaneously in the case of abnormally low reservoir pressure or reservoir permeability.

SUBSTANCE: method involves lowering flexible pipe to lower perforation orifices; performing initial injection of killing liquid via the flexible pipe into tubing space of well, wherein killing liquid volume is equal to production tubing volume; simultaneously discharging gas to flare line through newly created annular space between production tubing and flexible pipe lowered in the production tubing; serially injecting blocking solution and killing liquid through flexible pipe, wherein the blocking solution amount provides total perforation interval filling and killing liquid volume is equal to sum of flexible pipe volume and blocking solution volume; forcing blocking solution into bottomhole reservoir zone with simultaneously flexible pipe lifting within perforation interval and with keeping of backpressure in annular space; removing flexible pipe from well; opening circulation valve, for instance with the use of cable equipment and filling casing-formation annulus with killing liquid arranged over packer; executing technological time-delay; discharging gas accumulated during technological time-delay from tubing space and casing-formation annulus; equalizing killing liquid density in tubing space and casing-formation annulus by providing of circulation through opened circulation valve.

EFFECT: increased reliability of gas and gas condensate packing well killing.