DEVICE FOR CUTTING OFF AND CONTROLLING FLOW IN A WELL WITH ONE OR SEVERAL FORMATIONS Russian patent published in 2007 - IPC E21B34/06 

FIELD: hydrocarbon extractive industry.

SUBSTANCE: device includes pumping or fountain or gas-lifting or forcing assembly lowered into well on pipes column, including one or several mounting chambers. Positioned in each chamber are one or several detachable valves having a body. Body has pass-through channels, lock and external seals. Inside the body, controlling tool is positioned interconnected through a rod with locking element of "latch-saddle" type. In accordance to invention for functioning of detachable valve as cutoff plate and controller by pressing and releasing of its controlling tool due to increase and then decrease of mouth annular or tubular pressure, body is equipped with free or spring-loaded check valve. Controlling tool of detachable valve is made in form of rod with holder. Rod or latch or piston or holder is spring-loaded by resilient element relatively to the body. Piston with holder are located inside the body with possible, during each increase of mouth annular or tubular pressure, constriction of resilient element and movement to one side of rod and latch and outlet of holder from one stable position of engagement with body, and during each decrease of mouth annular or tubular pressure, vice versa, partial or full reverse movement of rod and latch under force from resilient element and engagement while holder is in another stable engagement with body.

EFFECT: increased efficiency and reliability of device.

1 cl, 27 dwg