# US 5,706,869 A · Filling the annulus between concentric tubes with resin > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,706,869 A - Document ID: US5706869A - Status: Granted - Kind: A - Application number: 08/653,494 - Filed: 1996-05-24 - Granted: 1998-01-13 - Earliest claimed: 1996-05-24 - Assignees: Acoust-A-Fiber Research and Development, Inc. - Inventors: Jerry M. Wolf; Hiten T. Shah; Steven J. Crosbie; James D. Crosby - Web page: https://patentgrep.com/patent/US5706869A ## CPC - F01N 13/18: Construction facilitating manufacture, assembly, or disassembly - B29C 70/025: {with particular filler} - B29C 70/84: by moulding material on preformed parts to be joined {(joining plastic parts by moulding B29C65/70)} - F01N 13/14: having thermal insulation {(exhaust manifolds F01N13/102)} - F16L 59/04: Arrangements using dry fillers, e.g. using slag wool - F01N 2310/02: Mineral wool, e.g. glass wool, rock wool, asbestos or the like - F01N 2470/24: Concentric tubes or tubes being concentric to housing, e.g. telescopically assembled - F01N: GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES (arrangements in connection with gas exhaust of propulsion units in vehicles B60K13/00; combustion-air intake silencers specially adapted for, or arranged on, internal-combustion engines F02M35/00; protecting against, or damping, noise in general G10K11/16) - 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) - F16L: PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL ## Abstract Concentric conduits are supplied for the purpose of minimizing heat transfer from within the inner conduit through the outer conduit. The air gap or annulus around the inner conduit is filled with a resin mixture which is mixed with vermiculite and mineral fiber to form a slurry. The slurry is pumped into an open end of the annulus to fill the annulus and enhance the heat insulation characteristics of the concentric conduits. ## Claims ### Claim 1 A process of filling the annulus between concentric conduits with fluid material comprising, providing concentric conduits secured together at one end and being of similar length, a bridge blocking the passage of fluid through said annulus where said conduits are secured together, said conduits terminating at a location remote from said bridge and forming an open inner passage in said inner conduit and an open annulus between said conduits, forming a bleed hole in the outer of the concentric conduits, said hole being near said bridge, inserting the discharge end of a nozzle into said open inner passage, injecting fluid material into said nozzle through a feed opening, blocking flow of said material from said nozzle into said open inner passage, discharging said fluid material from said nozzle only into said open annulus, exhausting any gaseous material in said annulus through said bleed hole while said fluid material flows in said annulus along said conduits toward said bridge, and determining when said annulus is full of said material by observing the discharge of fluid material through said bleed hole. ### Claim 2 (depends on 1) The process of claim 1 including withdrawing said nozzle from said conduits and leaving a gap in said annulus unfilled by said material where said conduits terminate. ### Claim 3 (depends on 2) The process of claim 2 including mixing vermiculite, fibers and phenol formaldehyde resin to form a slurry of said material prior to injecting said material into said nozzle. ### Claim 4 (depends on 3) The process of claim 3 wherein said material is a mixture of about 40-50% vermiculite, about 40-50% mineral fiber and about 8-12% phenol formaldehyde by weight. ### Claim 5 (depends on 4) The process of claim 4 wherein said vermiculite and mineral fiber comprise about 15-21% by volume of said slurry. ### Claim 6 (depends on 5) The process of claim 5 wherein said mineral fiber comprises amorphous calcium magnesium aluminum silicate having a melting point of about 1000.degree. C. and a dry density of about 80-300 kg/m.sup.3. ### Claim 7 (depends on 1) The process of claim 1 including mixing vermiculite, mineral fibers and phenol formaldehyde resin to form a slurry of said material prior to injecting said material into said nozzle. ### Claim 8 (depends on 7) The process of claim 7 wherein said material is a mixture of about 40-50% vermiculite, about 40-50% mineral fiber and about 8-12% phenol formaldehyde by weight. ### Claim 9 (depends on 8) The process of claim 8 wherein said vermiculite and mineral fiber comprise about 15-21% by volume of said slurry. ### Claim 10 (depends on 3) The process of claim 3 wherein said vermiculite and mineral fiber comprise about 15-21% by volume of said slurry. ### Claim 11 (depends on 1) The process of claim 1 wherein said material is a mixture of about 40-50% vermiculite, about 40-50% mineral fiber and about 8-12% phenol formaldehyde by weight.