FLUSHING UNIT OF DRILL BIT Russian patent published in 1994 - IPC

FIELD: drilling of holes. SUBSTANCE: drilling bit has body 1 with claws 2 and pins, roller bits 3, lengthened branch pipe 5. Drilling bit is provided with ball-and-socket joint in the form of pivot 4 with annular groove in the shape of part of sphere fastened in body for gripping of upper end of branch pipe 5. Annular protrusion is located in upper end of branch pipe 5. Supplementary packing 8 are uniformly attached over outer surface of lower end of branch pipe at acute angle to its axis. EFFECT: improved drilling capabilities. 1 dwg