METHOD FOR CEMENTING OIL AND GAS WELLS AND DEVICE FOR REALIZATION OF SAID METHOD Russian patent published in 2007 - IPC E21B33/14 E21B28/00 

FIELD: oil and gas extractive industry.

SUBSTANCE: in accordance to method, well is prepared, casing string is lowered into it, drill mud is removed from annular space by means of replacing it with buffer liquid with following replacement of buffer liquid by forcing cementing solution into tubular hollow and its following forcing into annular space of well with pressurization of circular space between casing string and walls of well borehole. Casing string is subjected to vibration effect with frequency equal to or divisible by resonance frequency of casing string at stages of removal of drill mud from annular space and its replacement with buffer liquid, filling of well borehole with cementing solution with its following forcing into annular space and during stiffening stage of cementing solution. For accelerated growth of durability and for fast restoration of structural connections in cementing solution at last stage intensiveness of vibration effect is decreased. Device contains vibration excitation device built on above-ground section of casing string, frequency transformer for powering the vibration excitation device and basic frequency generator for controlling aforementioned frequency transformer. Vibration excitation device consist of two unbalance electromechanical vibrators, made with parallel shafts with possible opposite rotation, mounted on above-ground section of casing string immediately below cementing head by means of vertically positioned supporting plates enveloping the casing pipe.

EFFECT: increased cementing quality.

2 cl, 2 dwg