DOWNHOLE FILTER Russian patent published in 2020 - IPC E21B43/08 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil and gas industry, particularly, to oil and gas filtration. Downhole filter comprises nipples, a coupling and at least one filter unit comprising a filter element with stringers laid parallel to the axis of the downhole filter between the limit rings, and coils of profiled wire wound on them. Each filtering unit comprises an inner core fitted on it by an external cylinder coaxially with preliminary tightening with radial holes and stringers made integral with the external cylinder. Connection of internal pipe and external cylinder is made through cross-pieces installed inside limiting rings.

EFFECT: higher bending strength while maintaining torsional strength and providing efficient cleaning.

7 cl, 1 tbl, 23 dwg