WELL REAMER Russian patent published in 2006 - IPC E21B7/28 

FIELD: drilling equipment, particularly devices, which provide well bore reaming within predetermined interval.

SUBSTANCE: reamer comprises pilot drilling bit, body with central and radial channels and throttle, rock-cutting members with coupler movably installed on guiding means and rock-cutting member movably installed in guiding slots of the body. The reamer also has hollow piston installed on lower body part. The body is made as leading pipe with beveled side guiding means. The guiding slots are formed in side body guiding means beveled upwards. The coupler is provided with support orifice for rock-cutting member receiving, wherein the rock-cutting member is installed in the guiding slots.

EFFECT: extended range of reamed application and increased efficiency.

4 cl, 1 dwg