Matrix fixed cutter drill bits and methods for manufacturing same

摘要

A fixed cutter drill bit for drilling a borehole in earthen formations includes a blank assembly and a matrix crown fixably mounted to the blank assembly. The blank assembly includes an annular mandrel and a plurality of elongate studs fixably coupled to the mandrel. The mandrel has a first end distal the crown and a second end engaging the crown. In addition, the mandrel includes a plurality of bores extending axially from the second end. Each elongate stud has a first end disposed within one of the bores and a second end disposed in the crown distal the mandrel.

主权项

1. A fixed cutter drill bit for drilling a borehole in earthen formations, the bit having a central axis and a cutting direction of rotation, the bit comprising:
a blank assembly including an annular mandrel and a plurality of elongate studs fixably coupled to the mandrel; a matrix crown fixably mounted to the blank assembly; wherein the mandrel is coaxially aligned with the central axis and has a first end distal the crown and a second end engaging the crown; wherein the mandrel includes a plurality of bores extending axially from the second end; wherein each elongate stud has a first end disposed within one of the bores and a second end disposed in the crown distal the mandrel; and wherein at least one elongate stud has a different length than the other elongate studs of the plurality of elongate studs.