WELL PLUGGING DEVICE Russian patent published in 1996 - IPC

FIELD: plugging of troubled intervals of well. SUBSTANCE: well plugging device has hollow body with container in its lower part. Container accommodates piston to divide the container hollow into above-piston and working spaces. The latter are filled with plugging material. Installed above container is signal gate and pulsator. Container has, at least, one discharge hole and jet chamber which is communicated with ambient space through discharge hole. Supply nozzle is installed in jet chamber. Intake nozzle is installed in the container upper part. Intake nozzle is communicated with above-piston space. Signal gate is installed in container for interaction with piston and communication of above-piston space with ambient space. Signal gate has flow area in its open position which is not less than flow area of inlet of intake nozzle. Flow area of discharge holes is taken from the relation f=Q-VF/R μ , where f is flow area of one discharge hole, sq. m; Q is working fluid volume flow rate supplied to pulsator cu.m/s; V is piston motion speed in container, m/s; F is working area of piston cross-section, sq.m; R is number of discharge holes; m is coefficient of fluid flow rate through discharge holes; Dp is preset pressure differential between jet chamber and ambient space, Pa; ρ is fluid density, kg/cu.m. EFFECT: higher reliability of well plugging device operation due to control of plugging process. 17 cl, 25 dwg