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

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil and gas industry and is intended for retention of mechanical impurities during filtration of formation fluids. Proposed device comprises hollow case with outer surface accommodating row of lengthwise slots with perforated holes. In the longitudinal grooves there are stringers in the form of spiral spring turns. On the external surface of the stringers there is a filtration shell in the form of spiral spring turns. On the filtering shell, at the place of perforated holes, reflecting rings are installed to cover direct filtration of the formation fluid. On the reflecting rings there are gates in the form of a cylinder with a row of longitudinal plates on the ends. Protective casing is made as composite in the form of paired thin-walled cylinders with lobes at ends and bands. Thin-wall cylinders in the middle part of the assembly are installed with possibility of end contact with bands and with formation of petals of annular gaps on the surface of the gates.

EFFECT: increased filtration area, possibility of filter alignment.

1 cl, 7 dwg