FIELD: process engineering.
SUBSTANCE: set of invention relates to drill bits for hard rocks. Drill bit comprises the head with radial base surface. At least one bearing shaft extends from said head and comprises the bearing seat surface. The taper fitted to make the bearing spin on the shaft includes the radially extending location surface. The first circular groove is made in said radially extending location surface. The second circular groove is made in said radially extending location surface of drill bit head. The first circular groove is aligned with at least the portion of the second circular groove. The protector ring features the sizes and shape for it to be tightly fitted in said first and second groove between the taper and drill bit.
EFFECT: higher reliability of protection against the ingress of abrasive particles.
33 cl, 12 dwg
