Patent ID: 8267203

Claim:
An erosion-resistant extension for an earth-boring rotary drill bit, the erosion-resistant extension comprising: a generally tubular body having a shape defining a fluid passageway extending through the generally tubular body, the generally tubular body comprising: an outer surface; an inner surface having a recess; a first end configured for attachment to a bit body of an earth-boring rotary drill bit; and an opposite, second end configured for attachment to a shank; and a generally tubular sleeve at least partially disposed within the fluid passageway, the generally tubular sleeve comprising: an erosion-resistant material lining the generally tubular body within the fluid passageway, the erosion-resistant material exhibiting an erosion resistance greater than an erosion resistance exhibited by a material of the generally tubular body; and at least one protrusion extending circumferentially at least partially around a longitudinal axis of the generally tubular sleeve on an exterior surface of the generally tubular sleeve, the recess being configured to receive the at least one protrusion therein when the generally tubular sleeve is at last partially disposed within the fluid passageway, wherein the at least one protrusion has a planar surface transverse to the longitudinal axis of the generally tubular sleeve, the planar surface being flush with an end surface of the second end of the generally tubular body.