CONTROLLED SHUTOFF VALVE Russian patent published in 2017 - IPC E21B34/06 E21B21/10 F16K15/02 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to downhole valve devices, namely, controlled valves which are used for shutting off a flow of well product in case of disturbance of set operation mode, and for shutting off the well bore when performing overhaul or temporary stopping of production. The proposed shutoff valve controlled by changes of pressure drop above and under it comprises a body with a sleeve gate including through and blind branch pipes provided with through holes on side walls, a check valve opened from the bottom by pressure at upper open end of the blind branch pipe, and a multi-stroke cam mechanism, one link of which is a pin fastened to the through branch pipe, and the second one is conjugated with the blind branch pipe of the cylindrical cam which is made in the form of sequence of communicating slots closed over cam circumference with alternating vertical and inclined sections (j-slot mechanism). The configuration of cam slots defines the series of pressures and pressure drops above the valve required to open it. Due to this sequence is unknown by authorised persons, the proposed cutoff valve prevents unauthorised withdrawal of formation fluid from the well. The cam can be a part of the blind pipe side surface or a separate part. A piston with a scraper can be connected to the cam from the bottom.

EFFECT: increased efficiency of controlled shutoff valve.

5 cl, 10 dwg