WELL CLEANING DEVICE Russian patent published in 2006 - IPC E21B37/00 

FIELD: oil and gas industry, particularly to develop wells contaminated with sand.

SUBSTANCE: device comprises hollow two-sectional body. The first body section is made as hydraulic cylinder with inlet channel and suction valve arranged downstream of the inlet channel in the first section. The first section also comprises hollow piston with pressure valve installed inside the first section and hollow piston part. Hollow rod is fixedly secured to hollow piston and may slide in axial direction relatively outlet part of the first section within piston stroke length. The second section has outlet liquid circulation channels and comprises the second part of hollow rod arranged in the second section. Above part is fixedly connected to inlet part of the second section so that the part and inner surface of the inlet part formed in the second section define annular cavity for mud accumulation. Outlet part of the section body section may be connected with means, which lowers device in well.

EFFECT: increased speed of well cleaning due to reduced time losses.

12 cl, 1 dwg