БУРОВОЕ ШАРОШЕЧНОЕ ДОЛОТО

摘要

FIELD: rock cutting tools, particularly roller drill bits. ^ SUBSTANCE: drill bit comprises legs with connection thread, cutters with axial channel and inserts located between the legs. Longitudinal grooves are formed on outer insert surfaces. The grooves are connected with axial cutter channel by radial channels. Peripheral cutter parts are provided with rock-cutting members brought into contact with well walls and defining longitudinal slot widths. Longitudinal slots have variable thickness along slot height and widen in top-bottom direction. ^ EFFECT: increased operational reliability due to improved face cleaning of mud. ^ 3 dwg