METHOD OF SHANK INSTALLATION IN WELL Russian patent published in 2020 - IPC E21B43/10 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil and gas industry, namely, to methods of installation and cementing shank tailings in borehole, including in side and horizontal shafts. Method comprises lowering a well string on a production pipe string with a detachable mechanism of the shank, installing it in the required interval, flushing the installation interval, cementing of shank, disconnection by means of withdrawal mechanism of process pipes with lifting before expectation hardening of cement, washing of barrel above shank and anticipation of hardening of cement. Preliminary determining the critical pressure above which the integrity of the exposed productive formation is disturbed, and the volume of the injected flushing liquid per unit time – the required injection rate, providing the rate of liquid lifting from the well, exceeding rate of precipitation of undissolved in liquid particles washed from well. After shank installation, well borehole is flushed with increasing pumping rate with pressure control not exceeding critical pressure until required rinsing fluid injection rate is achieved, at which liquid is pumped with volume making at least one volume of well from bottom of shank to wellhead. After the process pipes string disconnection, they are lifted before the flushing fluid circulation occurs during back flushing of the well, flushing fluid is pumped at the required injection rate till there is no incrustations of breakable cement in the pumped liquid.

EFFECT: enlarging functional capabilities due to operation in well with any zenith angle, flushing the well after installation of the shank without violating the integrity of the exposed formation by controlling injection of the flushing liquid by pressure and ensuring maximum removal of cement above shank by providing minimum possible distance between shank and process pipes with diverting mechanism during washing.

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