# US 5,706,864 A · Coolant conduits > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,706,864 A - Document ID: US5706864A - Status: Granted - Kind: A - Application number: 08/382,852 - Filed: 1995-02-03 - Granted: 1998-01-13 - Earliest claimed: 1994-02-09 - Assignees: EMS-Inventa AG - Inventors: Wolfgang Pfleger - Web page: https://patentgrep.com/patent/US5706864A ## CPC - B32B 1/08: Tubular products - B32B 3/28: characterised by a layer comprising a deformed thin sheet {, i.e. the layer having its entire thickness deformed out of the plane}, e.g. corrugated, crumpled (B32B29/08 takes precedence) - B32B 27/08: of synthetic resin - B32B 27/32: comprising polyolefins {(comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30)} - B32B 27/34: comprising polyamides - F16L 11/11: with corrugated wall - B32B 2270/00: Resin or rubber layer containing a blend of at least two different polymers - B32B 2307/558: Impact strength, toughness - B32B 2309/105: Thickness - B32B 2323/16: EPDM, i.e. ethylene propylene diene monomer - B32B 2377/00: Polyamides - B32B 2597/00: Tubular articles, e.g. hoses, pipes - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM - F16L: PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL ## Abstract A highly flexible and hydrolysis and burst resistant, coolant conduit comprising a plurality of layers of different polymer compatible with one another at the contact surfaces of the layers, the conduit being at least partially corrugated and at least some of the individual adjacent corrugations being connected to each other by at least one crossbar or rib. ## Claims ### Claim 1 A highly flexible and hydrolysis and burst resistant, coolant conduit comprising a plurality of layers of different polymers compatible with one another at the contact surfaces of the layers, the conduit being at least partially, including a plurality of ribs for connecting pairs of adjacent corrugations, wherein each corrugation is connected to a successive corrugation by at least one rib positioned in a first plane, said successive corrugation being connected to a next successive corrugation by at least one rib positioned in a second plane, said second plane being angularly offset from said first plane by a defined angle, wherein said ribs in the first plane and ribs in the second plane alternate in the longitudinal direction of the conduit between said pairs of corrugations, whereby said ribs between one adjacent pair of corrugations are angularly offset from said ribs between a next adjacent pair of corrugations, the external layer being made of a polymer selected from the group consisting of homopolyamides, copolyamides, blends thereof and mixtures thereof with one another and with other polymers. ### Claim 2 (depends on 1) A coolant conduit of claim 1 consisting of two layers of compatible polymers. ### Claim 3 (depends on 1) A coolant conduit of claim 1 comprising at least one internal layer, at least one intermediate layer and at least one external layer, the at least one intermediate layer capable of functioning as a barrier layer. ### Claim 4 (depends on 1) A coolant conduit of claim 1 having pairs of adjacent corrugations continuously connected by at least one rib. ### Claim 5 (depends on 1) A coolant conduit of claim 1 wherein at least one rib comprises a groove-like deformation of the conduit wall. ### Claim 6 (depends on 1) A coolant conduit of claim 1 having at least one internal layer inert to the coolant conveyed and an external layer resistant to pressure and mechanical influences. ### Claim 7 (depends on 1) A coolant conduit of claim 1 wherein the external layer is made of a member of the group consisting of homopolyamides, copolyamides of linear aliphatic monomers of 6 to 12 carbon atoms and cycloaliphatic monomers of 6 to 20 carbon atoms. ### Claim 8 (depends on 1) A coolant conduit of claim 1 wherein the external layer is made of a polymer selected from the group consisting of PA 6, PA 12 and PA 66 optionally modified by a member of the group consisting of processing additives and application additives. ### Claim 9 (depends on 6) A coolant conduit of claim 6 wherein the internal layer is made of a polymer selected from the group consisting of halogenated and non-halogenated homopolyolefins and copolyolefins and mixtures and blends thereof containing functional groups making it compatible with the external layer. ### Claim 10 (depends on 3) A coolant conduit of claim 3 wherein the internal layer is made of a polymer selected from the group consisting of halogenated and non-halogenated homopolyolefins and copolyolefins insufficiently compatible with the external layer and the intermediate layer is compatible with the internal layer and the external layer. ### Claim 11 (depends on 10) A coolant conduit of claim 10 wherein the intermediate is made of a polymer selected from the group consisting of a grafted polyolefin, a grafted copolyolefin, copolyolefin provided with functional groups by copolymerization, their blends with non-functionalized polymers, and blends of the said polymers connected to one another and optionally additional polymers. ### Claim 12 (depends on 9) A coolant conduit of claim 9 wherein the internal layer is made of a copolyolefin with grafted .alpha.-saturated dicarboxylic acids and optionally also containing non-grafted polyolefin and the external layer is made of a member of the group consisting of modified and non-modified PA 12. ### Claim 13 (depends on 11) A coolant conduit of claim 11 wherein the internal layer is made of PVDF, the external layer is made of a member of the group consisting of modified PA 6, and PA 12 and the intermediate layer is made of a blend of the polymers of the internal and external layers. ### Claim 14 (depends on 10) A coolant conduit of claim 10 wherein the internal layer is made of a blend of a member of the group consisting of a polyolefin and copolyolefin with EPDM, the intermediate layer is made of a member of the group consisting of a functionalized polyolefin and copolyolefin and the external layer is made of a member of the group consisting of modified and non-modified PA 12. ### Claim 15 (depends on 1) A coolant conduit of claim 1 wherein the wall thickness of the pressure burst resistant external layer is 25 to 95% of the total wall thickness. ### Claim 16 (depends on 3) A coolant conduit of claim 3 wherein the thickness of the intermediate layer is 0.1 to 0.2 mm. ### Claim 17 (depends on 1) A coolant conduit of claim 1 produced by co-extrusion of a multi-layered tube of the polymers and subsequent formation of the corrugation and groove shaped ribs by blow molding. ### Claim 18 (depends on 1) A coolant conduit of claim 1 produced by co-extrusion of a multi-layered tube of the polymers and subsequent formation of the corrugation and groove shaped ribs by suction molding.