# US 9,062,501 B2 · Downhole centraliser > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,062,501 B2 - Document ID: US9062501B2 - Status: Granted - Kind: B2 - Application number: 13/274,751 - Filed: 2011-10-17 - Published: 2012-06-07 - Granted: 2015-06-23 - Earliest claimed: 2010-12-01 - Assignees: Matrix Composites & Engineering Ltd. - Applicants: Aaron Begley; Peter Brendon Thomas Pezet - Inventors: Aaron Begley; Peter Brendon Thomas Pezet - Web page: https://patentgrep.com/patent/US9062501B2 ## CPC - E21B 17/1042: {Elastomer protector or centering means} - 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 downhole centralizer arranged to receive a downhole tubular has a tubular body with opposed ends and is formed of plastics material A respective end ring is mounted in the or each opposed end and is formed of a plastics material having a Youngs Moldulus no greater than that of the tubular body. ## Claims ### Claim 1 A downhole centraliser arranged to receive a downhole tubular, the centralizer comprising: a tubular body having opposed ends and being formed of plastics material; and at least one end ring mounted to an end of the tubular body, the or each end ring also being formed of a plastics material and having a Youngs modulus no greater than that of the tubular body, at least one end of the tubular body having a relatively thin wall section arranged to receive an end ring wherein, the or each end ring comprises an annular member arranged to engage with an inner surface of a relatively thin annular wall section, the or each relatively thin wall section of the tubular body being provided with a plurality of spaced projections or apertures and the or each annular member being provided with a corresponding plurality of spaced apertures or projections, each aperture being arranged to engage with a corresponding projection such that the end ring and the body are positively engageable. ### Claim 2 (depends on 1) A downhole centraliser according to claim 1, wherein a respective end ring is mounted to each of the opposed ends of the tubular body. ### Claim 3 (depends on 1) A downhole centraliser according to claim 1, wherein the tubular body and the or each end ring are formed of the same plastics material. ### Claim 4 (depends on 1) A downhole centraliser according to claim 1, wherein the or each end ring is engaged with the tubular body by means of an interference fit. ### Claim 5 (depends on 1) A downhole centraliser according to claim 1, wherein the or each end ring is positively engageable with the tubular body in a releasable manner. ### Claim 6 (depends on 1) A downhole centraliser according to claim 1, wherein the or each end ring has an inner face formed with a plurality of spaced inward extending projections which are arranged in use to bear on a tubular member about which the centraliser is mounted. ### Claim 7 (depends on 1) A downhole centraliser according to claim 1, wherein there is provided a seat at an inner end of the thin wall section for engagement with the annular member. ### Claim 8 (depends on 1) A downhole centraliser according to claim 1, wherein the or each end ring has a small degree of resilience enabling it to be urged inwardly upon engagement with the body and then springing outwardly upon release. ### Claim 9 (depends on 1) A downhole centraliser according to claim 1, wherein the or each end ring and the tubular body are provided with cooperating alignment and anti-rotation means. ### Claim 10 (depends on 9) A downhole centralizer according to claim 9, wherein the cooperating alignment and anti-rotation means comprise a plurality of spaced slots on one member and a corresponding plurality of spaced ribs on the other member, corresponding said slots and ribs being arranged to be interengaged. ### Claim 11 (depends on 1) A downhole centralizer according to claim 1, wherein the downhole centralizer is substantially rigid. ### Claim 12 (depends on 1) A downhole centralizer according to claim 1, wherein the or each end ring is provided with a plurality of spaced projections whilst the or each inner wall section is provided with a corresponding plurality of spaced apertures. ### Claim 13 (depends on 12) A downhole centralizer according to claim 12, wherein the or each projection is asymmetrical in having a tapered inner portion and an angular outer portion. ### Claim 14 A downhole centraliser arranged to receive a downhole tubular, the centralizer comprising: a tubular body having a first end with a thinned wall section and an inner surface, the tubular body being formed of a first plastics material, the inner surface having a plurality of spaced radial projections or apertures; and a first annular end ring having an outer surface, the first annular end ring being formed of a second plastics material, the first annular end ring having a Youngs modulus no greater than a Youngs modulus of the tubular body, the outer surface having a corresponding plurality of spaced radial apertures or projections, wherein the first annular end ring is mounted to the first end of the tubular body with the plurality of spaced radial projections or apertures of the inner surface positively engaging the corresponding plurality of spaced radial apertures or projections of the outer surface. ### Claim 15 (depends on 14) A downhole centraliser according to claim 14, wherein the tubular body further comprises a second end with the thinned wall section and the inner surface having the plurality of spaced radial projections or apertures, and further comprising a second annular end ring having the outer surface with the corresponding plurality of spaced radial apertures or projections, the second annular end ring being mounted to the second end of the tubular body with the plurality of spaced radial projections or apertures of the inner surface positively engaging the corresponding plurality of spaced radial apertures or projections of the outer surface. ### Claim 16 (depends on 14) A downhole centraliser according to claim 14, wherein the first and second plastic materials are a common plastics material. ### Claim 17 (depends on 14) A downhole centraliser according to claim 14, wherein the first annular end ring forms an interference fit with the first end of the tubular body. ### Claim 18 (depends on 14) A downhole centraliser according to claim 14, wherein the first annular end ring is releasably mounted to the first end of the tubular body. ### Claim 19 (depends on 14) A downhole centraliser according to claim 14, wherein the inner surface of the first end further comprises a seat for engagement with the first annular end ring. ### Claim 20 (depends on 14) A downhole centraliser according to claim 14, wherein the inner surface of the first end further comprises a plurality of spaced axial slots or ribs and the outer surface of the first annular end ring comprises a corresponding plurality of spaced axial slots or ribs, the plurality of spaced axial slots or ribs of the inner surface positively engaging the corresponding plurality of spaced axial slots or ribs of the outer surface.