Drill Bit and Cutter Element Having Chisel Crest With Protruding Pilot Portion
AssigneeSmith International, Inc.
InventorsScott D. McDonough, Amardeep Singh
Life of this patent
Estimating the term…
Abstract
A rolling cone drill bit includes a cutter element having a cutting portion with a chisel crest and a pilot portion extending beyond the chisel crest. The pilot portion includes a cutting surface that may be generally conical, or form a second chisel crest. The cutting tip of the pilot portion is supported by buttress portions which emerge from and extend beyond the flanks of the chisel crest to provide additional strength and support for the material of the pilot portion that extends beyond the height of the chisel crest.
Claims21
-45. (canceled)
A cutter element for a drill bit comprising:
- a base portion;
- a cutting portion extending from the base portion and comprising a cutting surface;
- wherein the cutting surface includes a first elongate chisel crest with flanking surfaces meeting in an elongate and a peaked ridge defining a crest height, and a pilot portion intersecting the chisel crest and extending above the crest height;
- wherein pilot portion comprises a second elongate chisel crest.
A drill bit for cutting a borehole having a borehole sidewall, corner and bottom, the drill bit comprising:
- a bit body including a bit axis;
- a rolling cone cutter mounted on the bit body and adapted for rotation about a cone axis;
- a cutter element having a base portion secured in the rolling cone cutter and a cutting portion extending therefrom;
- wherein the cutting portion comprising a first chisel crest with flanking surfaces tapering to form an elongate and peaked ridge defining a first crest height, and a pilot portion intersecting the first chisel crest and extending beyond the first crest height,
- wherein the pilot portion comprises a second chisel crest.
Dependencies are inferred from the claim text.