WELL BORE REAMER Russian patent published in 2007 - IPC E02F5/18 E21B7/28 

FIELD: drilling equipment, particularly machines for digging horizontal wells in the soil, namely reamers thereof.

SUBSTANCE: well bore reamer comprises body with working cavity for drilling mud containing, cutting members and drilling mud supply nozzle, which delivers drilling mud to well bore reaming zone. Above components are installed on the body. Reamer also has central drilling mud supply channel and line switch. Line switch comprises shell body, piston with channels for drilling mud forcing in reverse direction arranged in the shell body, valve carried by the piston and adapted to close channels thereof, lid with axial channel and retaining rings for piston travel limiting. Drilling mud supply channels, which deliver drilling mud to working cavity, are made in shell body. Piston is installed on shell body and may slide to open and close shell body orifices.

EFFECT: increased efficiency of well drilling due to decreased drilling mud consumption.

2 dwg