METHOD AND DEVICE FOR WELL FLUSHING Russian patent published in 2010 - IPC E21B37/00 

FIELD: oil and gas production.

SUBSTANCE: method includes lowering tail drilling or lifting pipes in string with device, its installation in specified interval of well. Prior to operation start, pressure is supplied into cavity of lifting or drilling pipe, and device is put into working position. Liquid supply is switched to circular space of well, and, while moving device down by connection making of lifting or drilling pipe, mechanical deposits are washed through water jet unit or are drilled by bottomhole motor. Carry-over of action products to surface is done via device and lifting or drilling pipe above it. On completion of operation, by supplying liquid in cavity of lifting or drilling pipe, device is changed into transport position, then lifted to surface. Device, comprising drain and radial channels, consists of movable hollow stem, reciprocal motion of which is maintained by spring, ball valve, mechanism of switchover to working and transport positions, sealing element, flow separator with inlet and outlet channels.

EFFECT: time of works performance and operational costs are reduced, production of carbohydrates is increased.

2 cl, 3 dwg