DEVICE FOR CLEANING WALLS OF PRODUCTION STRING AND BOTTOM HOLE Russian patent published in 2012 - IPC E21B27/00 E21B37/02 

FIELD: oil and gas industry.

SUBSTANCE: device includes in-series connected tubing string, hydraulic sludge pump, non-return valve, wing with a valve in the form of a gate valve, rubbish accumulating containers and brushers-scratches, gravity filter, lower and upper cross-flow filter, and movable sealing device for inter-tube space. Inner cavities of accumulating container of hydraulic sludge pump and tubing string are hydraulically connected to the tube which is located inside gravity filter, lower and upper cross-flow filter, which are made in the form of perforated tubes. Fine-meshed screen is installed on external surface of gravity filter. Movable sealing device for inter-tube space, which overlaps perforation holes of lower filter, is arranged on external surface of lower cross-flow filter with possibility of being moved in longitudinal direction. Ratio of coarse rubbish container volume to fine rubbish container volume is 1:(4-6), and lower and upper filters have holes with diameter of 8 to 10 mm.

EFFECT: increasing cleaning efficiency and enlarging technological capabilities of the device.

1 dwg