OPENING METHOD OF HIGH-PRESSURE STRATUMS, SATURATED BY STRONG BRINES Russian patent published in 2009 - IPC E21B21/08 

FIELD: civil engineering.

SUBSTANCE: invention elates to deep well construction technology, particularly to opening methods of producing formations. Method includes drilling and fixation of borehole up to top of high-pressure stratum, opening by drilling of high-pressure stratums with usage of measures of anti-fountain blowout. According to invention before lowering of string, fixing borehole up to top of productive stratum, in the range of thief formation, located directly under regional waterproof stratum, by method of frac job it is formed thief zone. After it is implemented fixation of borehole by intermediate casing string, providing communication of formed thief zone through wellhead necking with reserve capacitive fleet and ground-based pumping equipment ensured by sub-lifting of cement grout for 80-100 m up to previous casing shoe. Hereupon it is implemented opening by drilling of target high-pressure stratum. In case of brine-appearance it is implemented withdrawal of natural brine by pumping by ground-based pumping equipment or ensured by itself power of producing high-pressure formation by hole annulus into beforehand formed thief zone.

EFFECT: it provides ability of controlled opening of high-pressure stratums with anomalous output and pressure, saturated by strong brines, with higher degree of protection against spontaneous discharges and formation fluid flowing.

1 ex, 1 dwg