WELL REAMER Russian patent published in 1996 - IPC

FIELD: mining industry and construction; well drilling. SUBSTANCE: well reamer includes body with axial channel and means for connection with drill pipe string, pins secured to body and carrying roller cutters on their ends on bearings, stabilizer and wearing ring. Reamer has lubricator in each pin for lubricating roller cutter bearings. Lubricator is made in form of reservoir formed by hollow in pin body and filled with lubricant and spring-loaded piston accommodated in pin hollow. Reservoir hollow is communicated by radial channel with lubricating hollow of roller cutter bearing having nipple for lubricant supply, and through axial channel with hollow formed by pin and face surface and internal end surface of roller cutter. Pin body has additional channel whose hollow is communicated with lubricating hollow of the bearing in point diametrically opposite to the first channel and by means of additional axial channel and check valve accommodated in it, with hollow formed by pin end face and internal end surface of roller cutter. EFFECT: higher efficiency. 4 cl, 4 dwg