# US 12,215,549 B2 · Drill bit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,215,549 B2 - Document ID: US12215549B2 - Status: Granted - Kind: B2 - Application number: 18/049,472 - Filed: 2022-10-25 - Published: 2023-06-08 - Granted: 2025-02-04 - Earliest claimed: 2018-11-12 - Assignees: Ulterra Drilling Technologies, L.P. - Applicants: Ulterra Drilling Technologies, L.P. - Inventors: Jorge Arthur Silveus, III; Alfred Harold Skinner; Benjamin Chrest - Web page: https://patentgrep.com/patent/US12215549B2 ## CPC - E21B 10/43: characterised by the arrangement of teeth or other cutting elements - E21B 10/5673: {having a non planar or non circular cutting face} - E21B 10/55: with preformed cutting elements - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract A drill bit including a body having a face and a plurality of blades disposed on the face of the body. Each of the plurality of blades may have a row of cutters disposed thereon, and the rows of cutters may collectively define a cutting profile of the drill bit. At least some of the cutters along the cutting profile may have alternating positive back rake angles. The difference between a majority of back rake angles on adjacent cutters along the cutting profile may be less than 20°. ## Claims ### Claim 1 A drill bit, comprising: a body having a face and a central bit axis; and a plurality of blades disposed on the face of the body, each of the plurality of blades having a row of cutters disposed thereon, the rows of cutters collectively defining a cutting profile of the drill bit, wherein: wherein a nose region and a cone region of the face, at least six radially adjacent cutters of the cutters along the cutting profile having alternating positive back rake angles; at least some adjacent cutters of the cutters along the cutting profile have non-alternating back rake angles; and the difference between a majority of back rake angles on adjacent cutters along the cutting profile is less than 20°. ### Claim 2 (depends on 1) The drill bit of claim 1, wherein adjacent cutters of the at least some of the cutters along the cutting profile having alternating positive back rake angles are disposed on different blades. ### Claim 3 (depends on 1) The drill bit of claim 1, wherein at least some cutters of the row of cutters disposed on one blade of the plurality of blades have alternating positive back rake angles. ### Claim 4 (depends on 1) The drill bit of claim 1, wherein the at least some of the cutters along the cutting profile having alternating positive back rake angles include a first plurality of cutters and a second plurality of cutters, wherein each of the first plurality of cutters has a positive back rake angle within a first range, wherein each of the second plurality of cutters has a positive back rake angle within a second range different from the first range. ### Claim 5 (depends on 4) The drill bit of claim 4, wherein the difference of the average of the first range and the average of the second range is from 5 to 20°. ### Claim 6 (depends on 4) The drill bit of claim 4, wherein at least some of the first plurality of cutters is disposed on a first blade of the plurality of blades, and wherein at least some of the second plurality of cutters is disposed on a second blade of the plurality of blades. ### Claim 7 (depends on 6) The drill bit of claim 6, wherein the first blade and the second blade are adjacent to each other. ### Claim 8 (depends on 4) The drill bit of claim 4, wherein the plurality of blades includes a first set of blades and a second set of blades, wherein at least some of the cutters disposed on the first set of blades have back rake angles within the first range, wherein at least some of the cutters disposed on the second set of blades have back rake angles within the second range, and wherein the first set of blades and the second set of blades are arranged in an alternating manner. ### Claim 9 (depends on 4) The drill bit of claim 4, wherein the first plurality of cutters includes a first set of at least two adjacent cutters along the cutting profile, and wherein the second plurality of cutters includes a second set of at least two adjacent cutters along the cutting profile. ### Claim 10 (depends on 9) The drill bit of claim 9, wherein the first set and the second set are arranged in a consecutive manner along the cutting profile. ### Claim 11 (depends on 1) The drill bit of claim 1, wherein the difference between the back rake angles on two adjacent cutters is greater than the difference between the back rake angles on another two adjacent cutters that are disposed radially further outward. ### Claim 12 (depends on 1) The drill bit of claim 1, wherein the face comprises a shoulder section disposed radially outward from the cone and nose regions, wherein at least some of the cutters within the shoulder section have alternating positive back rake angles. ### Claim 13 (depends on 1) The drill bit of claim 1, wherein at least some of the cutters having alternating positive back rake angles also have alternating side rake angles. ### Claim 14 (depends on 1) The drill bit of claim 1, wherein the rows of cutters are rows of primary cutters, and wherein each of the plurality of blades further includes a row of back-up cutters. ### Claim 15 (depends on 1) The drill bit of claim 1, wherein the rows of cutters are rows of back-up cutters, and wherein each of the plurality of blades further includes a row of primary cutters. ### Claim 16 (depends on 1) The drill bit of claim 1, wherein at least one of the blades comprises an inner region and an outer region rotationally offset from the inner region, and wherein at least some of the cutters having alternating positive back rake angles are disposed on at least one of the inner region, the outer region, or combinations thereof. ### Claim 17 (depends on 1) The drill bit of claim 1, wherein the rows of cutters further comprise cutters that do not have alternating positive back rake angles along the cutting profile. ### Claim 18 (depends on 1) The drill bit of claim 1, wherein the at least some adjacent cutters of the cutters along the cutting profile having non-alternating back rake angles are radially outward of the at least six radially adjacent cutters. ### Claim 19 A method of using a drill bit, comprising: drilling a borehole with a drill bit, wherein the drill bit comprises: a body having a face and a central bit axis; and a plurality of blades disposed on the face of the body, each of the plurality of blades having a row of cutters disposed thereon, the rows of cutters collectively defining a cutting profile of the drill bit, wherein: wherein a nose region and a cone region of the face, at least six radially adjacent cutters of the cutters along the cutting profile have alternating positive back rake angles; at least some adjacent cutters of the cutters along the cutting profile have non-alternating back rake angles; and the difference between a majority of back rake angles on adjacent cutters along the cutting profile is less than 20°.