DRILL STRING CIRCULATION VALVE Russian patent published in 2025 - IPC E21B21/10 

FIELD: mining.

SUBSTANCE: invention relates to oil and gas industry. Device comprises a tubular body, an inlet adapter with a central channel, a spool-type bushing with two transverse bypass holes and a central channel, inside which a seat is placed. Bushing is attached to the shank, made with a central channel, and is installed inside the housing with possibility of sliding and contains a spring pressing the spool bushing to the end of the input sub, and two circulation ports with transverse holes fixed in the housing. Circulation ports are closed by the bushing in the inactive mode, in which the fluid is pumped through the drill string and are open with possibility of communication with inner space of drill string when circulation valve is in active mode. Deformable activating ball is lowered from the surface down the drill string. Two steel locking balls, each smaller than the deformable activating ball, are lowered one after another from the surface down the drill string to block the fluid flow through the circulation ports. Inside the outlet adapter there is a device for gripping balls passing through the seat with the fluid medium flow. Device comprises a deformable locking ball of a smaller size than each of the two steel locking balls, and bushing transverse bypass holes comprise a stop cavity with a spherical profile on the outer surface of the bushing, located on the seat side, made with the possibility of fixing the valve with a deformable locking ball in the cavity in the bushing bypass hole in one of the circulation ports and blocking the fluid flow through the said circulation port, leaving the second circulation port open.

EFFECT: increased service life and reliability, provided multiple switching of flow of drilling mud, including mudding materials, from inner space of drill string to annular space, bypassing elements of assembly of drill string downstream, providing fixation of valve.

3 cl, 9 dwg