# US 12,180,788 B2 · Drill string with centralizer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,180,788 B2 - Document ID: US12180788B2 - Status: Granted - Kind: B2 - Application number: 17/393,212 - Filed: 2021-08-03 - Published: 2022-12-08 - Granted: 2024-12-31 - Earliest claimed: 2021-06-03 - Assignees: Halliburton Energy Services, Inc. - Applicants: Halliburton Energy Services, Inc. - Inventors: Alben D'Silva; Philip Park Hung Leung; Steven Graham Bell - Web page: https://patentgrep.com/patent/US12180788B2 ## CPC - E21B 17/1057: {Centralising devices with rollers or with a relatively rotating sleeve (E21B17/1014 takes precedence)} - E21B 17/1078: {Stabilisers or centralisers for casing, tubing or drill pipes (E21B17/1007 - E21B17/1064 take precedence)} - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract A drill string for drilling a borehole. The drill string may include a downhole motor operable to rotate the drill string and a centralizer assembly. The centralizer assembly may include an outer housing, a lower sub threadably engaged with the outer housing, and a centralizer. The centralizer may include a single eccentric blade, an internal shoulder positioned between the outer housing and the lower sub, and an alignment profile to align the centralizer in an azimuthal position relative to the drill string. The centralizer may be retainable in the aligned azimuthal position by the alignment profile and the internal shoulder being engaged by the outer housing and the lower sub. ## Claims ### Claim 1 A drill string for drilling a borehole, the drill string comprising: a downhole motor operable to rotate the drill string; and a centralizer assembly comprising: an outer housing; a lower sub threadably engaged with the outer housing; wherein at least one of the outer housing or the lower sub comprises a mating profile located on an axially oriented face; and a centralizer comprising: a single eccentric blade; an internal shoulder extending radially inward from and azimuthally around an inner circumference of the centralizer, wherein the internal shoulder is positioned between the outer housing and the lower sub; and at least one alignment profile located on at least one axially oriented face to align the centralizer in an azimuthal position relative to the drill string by engagement with the at least one mating profile, the centralizer being retainable in the aligned azimuthal position by the engagement of the at least one alignment profile and the at least one mating profile and the internal shoulder being engaged by the threaded engagement of the outer housing and the lower sub. ### Claim 2 (depends on 1) The drill string of claim 1, wherein the alignment profile and the mating profile each comprise teeth. ### Claim 3 (depends on 1) The drill string of claim 1, wherein either the alignment profile or the mating profile comprises splines and the other of either the alignment profile or the mating profile comprises grooves. ### Claim 4 (depends on 1) The drill string of claim 1, wherein the alignment profile is shaped to engage with rollers to allow rotation in a first direction and prevent rotation in a second direction opposite the first direction. ### Claim 5 (depends on 1) The drill string of claim 1, further comprising a bearing assembly, wherein the centralizer assembly is either coupled to the bearing assembly or the centralizer assembly is a subassembly of the bearing assembly. ### Claim 6 (depends on 5) The drill string of claim 5, further comprising a drill bit, wherein the centralizer is positioned on the drill string between the bearing assembly and the drill bit. ### Claim 7 A method for drilling a borehole with a drill string, the method comprising: positioning a centralizer of a centralizer assembly such that an internal shoulder of the centralizer extending radially inward from and azimuthally around an inner circumference of the centralizer is between an outer housing of the centralizer assembly and a lower sub of the centralizer assembly, wherein at least one of the outer housing or the lower sub comprises a mating profile located on an axially oriented face and the centralizer comprises a single eccentric blade; azimuthally aligning the centralizer relative to the drill string via at least one alignment profile on the centralizer located on at least one axially oriented face by engaging the alignment profile with the at least one mating profile; threadably engaging the lower sub with the outer housing to engage the internal shoulder and retain the centralizer in the aligned position using the at least one alignment profile being engaged with the at least one mating profile; and drilling the borehole using the drill string and the centralizer assembly. ### Claim 8 (depends on 7) The method of claim 7, further comprising centralizing the drill string within the borehole while drilling the borehole via the centralizer. ### Claim 9 (depends on 7) The method of claim 7, further comprising supporting a driveshaft of the drill string via a bearing assembly, wherein the centralizer assembly is either coupled to the bearing assembly or the centralizer assembly is a subassembly of the bearing assembly. ### Claim 10 (depends on 9) The method of claim 9, wherein the centralizer is positioned on the drill string between the bearing assembly and a drill bit of the drill string. ### Claim 11 (depends on 7) The method of claim 7, wherein the alignment profile and the mating profile each comprise teeth. ### Claim 12 (depends on 7) The method of claim 7, wherein either the alignment profile or mating profile comprises splines and the other of either the alignment profile or the mating profile comprises grooves. ### Claim 13 (depends on 7) The method of claim 7, wherein aligning the centralizer relative to the drill string comprises: rotating the centralizer in a first direction to align the centralizer; and engaging the alignment profile with rollers to prevent rotation in a second direction opposite the first direction. ### Claim 14 A centralizer assembly for use with a drill string, the centralizer assembly comprising: an outer housing; a lower sub threadably engaged with the outer housing; wherein at least one of the outer housing or the lower sub comprises a mating profile located on an axially oriented face; and a centralizer comprising: a single eccentric blade; an internal shoulder extending radially inward from and azimuthally around an inner circumference of the centralizer, wherein the internal shoulder is positioned between the outer housing and the lower sub; and at least one alignment profile located on at least one axially oriented face to align the centralizer in an azimuthal position relative to the drill string by engagement with the at least one mating profile, the centralizer being retainable in the aligned azimuthal position by the engagement of the at least one alignment profile and the at least one mating profile and the internal shoulder being engaged by the threaded engagement of the outer housing and the lower sub. ### Claim 15 (depends on 14) The centralizer of claim 14, wherein the alignment profile and the mating profile each comprise teeth. ### Claim 16 (depends on 14) The centralizer of claim 14, wherein either the alignment profile or the mating profile comprises splines and the other of either the alignment profile or the mating profile comprises grooves. ### Claim 17 (depends on 14) The centralizer of claim 14, wherein the alignment profile is shaped to engage with rollers to allow rotation in a first direction and prevent rotation in a second direction opposite the first direction.