DOWNHOLE FILTER WITH FLUSHING WITHOUT SURFACING Russian patent published in 2014 - IPC E21B43/08 

FIELD: oil-and-gas industry.

SUBSTANCE: proposed device tail pipe fitted at pump inlet to extend through packer, mid pipe plugged from above to make with tail pipe a concentric chamber plugged from below, accumulating pipe of solid particles, cylindrical filtration element arranged between tail pipe and accumulating pipe. Concentric chamber has radial channels arranged directly above and below the packer. Horizontal perforated girths are arranged between radial channels in mid pipe, mid pipe being furnished with through holes. Spring loaded top and bottom valves rigidly connected by rod are arranged on both sides of said horizontal girths. Leaky piston is arranged above top valve spring, piston diameter being equal to top valve diameter. Elasticity of top spring exceeds that of bottom spring.

EFFECT: expanded performances.

7 dwg