WELL COMPLETION METHOD IN CONDITIONS OF ABNORMALLY HIGH FORMATION PRESSURE Russian patent published in 2024 - IPC E21B33/14 E21B43/10 

FIELD: mining.

SUBSTANCE: invention relates to a method of well completion in conditions of abnormally high formation pressure (AHFP). Method includes drilling of well with deepening of bottomhole in repression mode. Method also involves stopping drilling and casing the well with a casing string lowered to the bottom. It also includes cementing the annular space of the casing string from its shoe to the required mark. Also, the method involves opening of the productive formation with AHFP from the cemented casing string by perforation channels. Completion of the well is carried out with reduced effect of AHFP of the productive formation. Deepening of the well bottom is stopped above the productive formation in the rocks overlying it. Interval of overlying rocks from the productive formation to the bottomhole is taken based on the possibility of screening the well from the effect of the productive formation. Then a casing string is lowered into the well to the bottom, the shoe of which is installed in the rocks overlapping the productive formation, and in this position the annular space is cemented. Further, channels are drilled from the cemented casing through the interval of overlapping rocks in differential pressure mode and they are used to drilling-in the productive formation. Shoe of the lowered casing string is equipped with holes with magnetic marks positioning them and drilled plugs.

EFFECT: reduction of negative effect of AHFP of productive formation on completion of well, reduction of accident rate of operations, colmatation of formations, improvement of quality of well casing and efficiency of well production as a whole.

1 cl, 3 dwg