CIRCULATING WELL SUB Russian patent published in 2023 - IPC E21B21/10 

FIELD: oil and gas industry.

SUBSTANCE: device contains a housing with radial holes, a tubular-shaped coupling with radial holes, a tubular-shaped sliding coupling with radial holes and a seat configured to move in the coupling. The inner surface of the housing has a threaded coupling and includes an upper annular projection, the first lower annular projection facing the upper end of the housing and located at a distance in the axial direction from the upper annular projection, the second lower annular projection, the radial holes of the housing are located between the upper annular and the first lower annular the housing protrusions are inclined and include detachably connected hydraulic monitor nozzles. The coupling includes an upper and a lower end and a passage hole between them, a threaded coupling on the outer surface for connection with the threaded coupling on the inner surface of the body, the outer surface of the coupling has an annular groove. The inner surface of the coupling includes a multitude of keys spaced around the circumference. The circumferential upper radial holes are located towards the upper end of the sliding sleeve but below the upper seat. The sliding sleeve includes an upper annular projection, a multitude of circumferentially arranged axial projections, an intermediate annular projection, and a lower annular projection, a spring bias element located around the outer surface of the sliding sleeve. Grooves are made on the outer surface of the lower end of the sliding coupling; the lower radial holes of the sliding coupling are located around the circumference and are made between its inner and outer surfaces and are located above the upper annular projection of the sliding coupling.

EFFECT: activation and deactivation of the sub is simplified with the ability to perform an unlimited number of such operations and to provide flushing both as a separate operation and directly during the drilling process.

1 cl, 9 dwg