FIELD: oil and gas industry.
SUBSTANCE: tool comprises of a housing adapted to attach to a drill string and defining a fluid flow channel, a sleeve disposed rotatably around the tool housing and containing one or more gripping members on its outer portion which are adapted to grip the borehole wall, a drive shaft extending through the tool housing and comprising a central gear, at least one drive gear attached rotatably to the sleeve and designed to engage the internal sleeve portion and the central gear, a pump mechanism attached to the drive shaft to receive power transmitted by the rotation of the drive shaft. The pump is designed to increase the pressure of the fluid within the flow channel.
EFFECT: satisfactory borehole cleaning.
20 cl, 7 dwg
