# US 2017/0284166 A1 · Solid-core filament-wound composite mandrel > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0284166 A1 - Document ID: US20170284166A1 - Status: Published application - Kind: A1 - Application number: 15/475,970 - Filed: 2017-03-31 - Published: 2017-10-05 - Earliest claimed: 2016-04-01 - Assignees: Schlumberger Technology Corporation - Inventors: Kyle Tse; Colby Jarrett - Web page: https://patentgrep.com/patent/US20170284166A1 ## CPC - E21B 33/1208: {characterised by the construction of the sealing or packing means (E21B33/1277 takes precedence)} - B29C 53/56: Winding and joining, e.g. winding spirally {(winding in general B65H)} - B29C 53/822: {Single use mandrels, e.g. destructible, becoming part of the wound articles (B29C53/825 takes precedence)} - B29C 53/824: {collapsible, e.g. elastic or inflatable; with removable parts, e.g. for regular shaped, straight tubular articles (B29C53/825 takes precedence)} - B29C 70/32: on a rotating mould, former or core - E21B 33/134: Bridging plugs - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) ## Abstract A technique for manufacturing a millable bridge plug for plugging of a wellbore during, for example, a fracturing operation. A bridge plug is constructed with an obstructed internal passage. The obstructed internal passage is formed by winding a composite material about a wrapping mandrel having at least one cylindrical part and a solid part coupled thereto. The cylindrical part is removed after a curing process leaving a mandrel with a plugged internal passageway upon which a seal member combined with a plurality of slips for engaging a surrounding wall, e.g. a surrounding wellbore wall, may be coupled. ## Claims ### Claim 1 A mandrel for substantially preventing fluid flow in a wellbore, the mandrel comprising: an outer mandrel member having an inner surface that defines a channel that extends from a first end of the outer mandrel member to a second end of the outer mandrel member; and a plug positioned within the channel between the first end and the second end, the plug contacting the inner surface of the outer mandrel member at a plug interface, wherein the inner surface has an inner diameter between the first end of the outer mandrel member and the plug interface, and wherein the inner surface has an interface diameter at the plug interface, wherein the interface diameter is greater than the inner diameter. ### Claim 2 (depends on 1) The mandrel of claim 1, wherein the outer mandrel member comprises a composite material. ### Claim 3 (depends on 1) The mandrel of claim 1, wherein the plug has a biconic shape. ### Claim 4 (depends on 1) The mandrel of claim 1, wherein the inner diameter is a first inner diameter, and wherein the inner surface has a second inner diameter between the second end of the outer mandrel member and the plug interface, and wherein the first inner diameter is substantially equal to the second inner diameter. ### Claim 5 (depends on 1) The mandrel of claim 1, wherein the plug is positioned in a center of the channel. ### Claim 6 (depends on 1) The mandrel of claim 1, wherein the plug comprises a non-metallic solid. ### Claim 7 A bridge plug for substantially preventing fluid flow in a wellbore, the bridge plug comprising: a mandrel comprising: an outer mandrel member having an inner surface that defines a channel that extends from a first end of the outer mandrel member to a second end of the outer mandrel member, and a plug positioned within the channel between the first end and the second end, the plug contacting the inner surface of the outer mandrel member at a plug interface, wherein the inner surface has an inner diameter between the first end of the outer mandrel member and the plug interface, and wherein the inner surface has an interface diameter at the plug interface, wherein the interface diameter is greater than the inner diameter; a seal member selectively actuatable into sealing engagement with an inner surface of the wellbore; and a plurality of slips actuatable into sealing engagement with the inner surface of the wellbore. ### Claim 8 A method of forming a mandrel for substantially preventing fluid flow in a wellbore, the method comprising: coupling a first and a second wrapping mandrel to a plug to form a single wrapping mandrel; winding the single wrapping mandrel with a composite material to form an outer mandrel member, the plug contacting an inner surface of the outer mandrel member at a plug interface; and detaching the first and the second wrapping mandrels from the plug, wherein the plug remains in a channel formed by the outer mandrel member, wherein the inner surface has an inner diameter between a first end of the outer mandrel member and the plug interface, and wherein the inner surface has an interface diameter at the plug interface, wherein the interface diameter is greater than the inner diameter. ### Claim 9 (depends on 8) The method of claim 8, further comprising: applying a coating material onto each of the first and second mandrels. ### Claim 10 (depends on 8) The method of claim 8, further comprising: coupling a seal member to the mandrel, the seal member being selectively actuatable into sealing engagement with an inner surface of the wellbore; and coupling a plurality of slips to the mandrel, the plurality of slips being actuatable into sealing engagement with the inner surface of the wellbore. ### Claim 11 (depends on 8) The method of claim 8, wherein coupling the first and the second wrapping mandrels to the plug comprises at least one of threading, friction fitting, and mechanical interference. ### Claim 12 (depends on 8) The method of claim 8, wherein the inner diameter is a first inner diameter, and wherein the inner surface has a second inner diameter between a second end of the outer mandrel member and the plug interface, and wherein the first inner diameter is substantially equal to the second inner diameter. ### Claim 13 (depends on 8) The method of claim 8, wherein the plug is positioned in a center of the channel. ### Claim 14 (depends on 8) The method of claim 8, wherein the plug comprises a non-metallic solid.