FIELD: instrument engineering.
SUBSTANCE: invention relates to the field of a cutting tool, in particular to annular drill bits for deep drilling with mechanical attachment of polyhedral throwaway plates and cutting inserts for their equipment. Drill comprises a body, cutting inserts and fastening elements. Cutting inserts are mounted in pairs, one of their bases arranged in the housing grooves and are fixed tangentially on its annular surface at the cutting end of the drill bit, with the placement of adjacent longitudinal cutting edges of the paired cutting inserts, if it is related to the front plate, the placement is on the drill outer diameter, and if it is related to the back plate, the placement is on the inner diameter of the drill, with overlapping of the overall mean diameter between their other adjacent longitudinal cutting edges, paired outer longitudinal cutting edges, installed on the outer and inner diameters of the drill. Design features of the drill are presented and variants of polyhedral cutting inserts for the drill are disclosed.
EFFECT: durability of drills is increased, the laboriousness of the drilling process for small-diameter holes is reduced.
28 cl, 17 dwg
