HYDRODYNAMIC FILTER WITH IMPULSE FLUSHING Russian patent published in 2010 - IPC E21B43/08 E21B34/06 

FIELD: process engineering.

SUBSTANCE: invention relates to mining, particularly to oil-and-gas industry and can be used for filtration of downhole fluid from mechanical impurities. Proposed filter consists of impulse flushing appliance with two perforated tubes with regularly arranged orifices. Tubular filtration elements are arranged nearby said tube orifices. Second tube is located below the first one. Impulse flushing appliance represents a stepped sleeve with one end furnished with threaded section divided by ledge for tubes to rests upon and jointing their threaded ends and the other end representing a barrel that communicates tube inner spaces at pressure difference. Said barrel has openings made on its wall and valve arranged at its end face. Sleeve outer surface has a guide for outer barrel that represents a circular groove accommodating a thrust-damper. Outer barrel is fitted concentric with aforesaid barrel to move there along and has openings on the wall nearby opening lower edge and retainer on its lower end face. Note here that plug is fitted on lower tube end that represents a container-collector.

EFFECT: higher reliability of filter operation.

7 cl, 5 dwg