CASING STRING CEMENTING METHOD Russian patent published in 2020 - IPC E21B33/14 

FIELD: soil or rock drilling; mining.

SUBSTANCE: invention relates to construction of oil and gas wells, namely to cementing of casing strings. In compliance with this method, casing string is cemented in different geological conditions. That is ensured by pumping of grouting mortar inside casing string and its pumping into annular space of the well. Cementing is provided at increased consumption of grouting mortar limited by hydraulic fracturing pressure of the formation. At the same time pumping of grouting mortar inside the casing string is performed at the rate exceeding the critical flow rate at which vacuum occurs in the jet of the grouting mortar. To this end, a throttle with a nozzle of specified cross-section is installed above the shoe of the casing string. By means of this throttle required hydrodynamic pressure is created at the specified flow rate of grouting mortar, aimed at reduction of value of hydrostatic pressure of plugging solution column in casing string.

EFFECT: technical result is improvement of quality of cementing of casing strings.

1 cl, 2 tbl, 2 dwg