BY-PASS DEVICE FOR WELL FLUSHING Russian patent published in 2022 - IPC E21B21/10 E21B34/10 

FIELD: oil production.

SUBSTANCE: invention relates to oil production, namely to bypass devices for flushing a well, intended for use in conjunction with a set of tools for cutting a window in a casing string and sidetracking with a hydraulic anchor. The bypass device for flushing the well contains a hollow body with a threaded protrusion in its lower part, an internal thread in the upper part and upper radial holes and a lower hole with mounted nozzles. A protrusion is made in the lower part of the central channel of the housing. The housing contains a piston containing the middle, upper and lower sections. The middle section of the piston is made with the possibility of connection with the body of the device by means of a shear screw, in each of the upper and lower sections of the piston there is a longitudinal channel and an annular space. An expansion is made in the internal cavity of the body. The piston is made with the possibility of linear movement between the position in which the central channel of the device body is blocked by connecting the middle section of the piston to the device body, the upper radial openings of the body communicate with the longitudinal channel and the annular space of the upper section of the piston, to a position with a stop against the protrusion of the lower part of the central channel , in which the central channel of the device body is open, the upper radial holes are blocked by the upper section of the piston. In both of these positions, the lower bore communicates with the expansion, the longitudinal channel and the annulus of the lower portion of the piston.

EFFECT: prevention of premature activation of the hydraulic anchor from the action of excessive annular or in-line pressure during descent into the well, the possibility of backwashing through the device without affecting the pressure drop on the anchor.

2 cl, 2 dwg