WELL STRAINER Russian patent published in 2012 - IPC E21B43/08 

FIELD: oil and gas industry.

SUBSTANCE: well strainer includes frame, external and internal slot-type filter elements concentrically installed on tubular frame with formation of vertical channels, sludge pit connected to vertical channels, upper connection pipe connected to the pump suction. Slot-type filter elements consist of longitudinal prismatic bars and wound prismatic profile, which are connected to each other. At that, filter elements are arranged outside and inside tubular frame and supported on longitudinal bars, thus forming external and internal vertical channels between longitudinal bars and tubular frame and central cylindrical cavity in internal slot-type filter element. At that, external vertical channels are tightly covered from above and connected to sludge pit in lower part. Internal vertical channels are tightly covered from below and connected from above to upper connection pipe. Central cylindrical cavity is separated from upper connection pipe with a valve and connected to the sludge pit.

EFFECT: improving cleaning quality of formation fluid, increasing service life of strainer and reducing labour intensity for its manufacture.

4 cl, 2 dwg