WELL CLEANING AND FLUSHING DEVICE Russian patent published in 2006 - IPC E21B37/00 E21B21/00 

FIELD: well operation and repair, particularly to clean well of mud, sand and sludge deposits.

SUBSTANCE: well cleaning and flushing device comprises body with radial orifices and packer located above the orifices. Hollow rod is arranged in the body so that the rod is concentric to the body. The rod has perforated orifices and may perform limited downward movement. The body is rigidly connected with liner provided with check valve arranged from liner bottom. The check valve is made as a plate sealing liner interior. The plate may rotate upwards about its edge by means of hinge and is provided with opening-closing force regulator made as additional load. The liner is provided with partition having throttle channel located over check valve. The packer is formed as self-sealing collar to permit liquid flow in bottom-top direction. The body is provided with extensions formed on upper edge thereof and with cylindrical extension arranged below radial windows. The cylindrical extension is formed on inner surface. The body is fixed relatively hollow rod by shear members. The perforated rod orifices are grouped in two rows, namely in upper and lower ones. In initial position lower perforated orifices of the rod are closed with the cylindrical extension, upper orifices are closed with bush fixed relatively hollow rod by thread. The bush has depressions formed on lower edge thereof and adapted to cooperate with body extensions when lower perforated orifices are opened. The hollow rod is provided with sealing member arranged on rod outside between upper and lower perforated orifices above the body. The sealing member isolates body interior during lower perforated orifices opening. The hollow rod is connected with flow string from top thereof. The liner may cooperate with sludge and sand deposits present in well bore and with well bottom.

EFFECT: provision of controllable speed of sludge and sand deposits in pipe string and possibility of well flushing in single trip.

2 dwg