A multi-layer composite in the form of a hollow body enclosing an interior space (2) is proposed, consisting of three or four layers: an inner layer (3) adjoining the interior space (2), a middle layer (4) adjoining the latter and an outer layer (5) adjoining the middle layer (4) and closing the multi-layer composite (1) to the outside. If necessary, there is a further innermost layer (8) which directly adjoins the said inner layer (3) and is equipped with a conductive finish. The inner layer (3) is based on polyamide 6, the middle layer (4) is based on EVOH, and the outer layer (5) is based on a mixture of (A) polyamide 6 and (B) at least one other polyamide selected from the following group: polyamide 612, polyamide 614, polyamide 616 and polyamide 618.

A hydrogen-filling hose includes reinforcing layers provided coaxially layered between an inner surface layer and an outer surface layer that are coaxially layered. The inner surface layer is formed of a thermoplastic resin and has a gas permeation coefficient of dry hydrogen gas of 1×10.sup.−8 cc.Math.cm/cm.sup.2.Math.sec..Math.cmHg or less at 90° C. A flow path formed by the inner surface layer has a diameter of 10 mm or more and 25 mm or less. The reinforcing layers includes four layers or more and eight layers or less, and each of the reinforcing layers has a spiral structure that is formed by spirally winding a metal wire material. Pricking holes extending through the outer surface layer in a thickness direction are dispersedly provided therein.

The present invention relates to a multilayer tubular structure (MLT) intended for the transport of fluids, in particular of petrol, especially alcohol-containing petrol, comprising, from the outside inwards, at least one barrier layer (1) and at least one inner layer (2) located below the barrier layer,

said inner layer (2), or all the layers (2) and the other optional layers located below the barrier layer, containing on average from 0 to 1.5% by weight of plasticizer relative to the total weight of the composition of the layer (2) or to the total weight of all the compositions of the layers (2) and the other optional layers located below the barrier layer, respectively,
said inner layer (2) predominantly comprising at least one polyamide of aliphatic type or consisting of more than 75% of aliphatic units, said aliphatic polyamide being chosen from: a polyamide denoted A, having a mean number of carbon atoms per nitrogen atom, denoted C.sub.A, of from 4 to 8.5, advantageously from 4 to 7; a polyamide denoted B, having a mean number of carbon atoms per nitrogen atom, denoted C.sub.B, of from 7 to 10, advantageously from 7.5 to 9.5; a polyamide denoted C, having a mean number of carbon atoms per nitrogen atom, denoted C.sub.C, of from 9 to 18, advantageously from 10 to 18;
with the proviso that when said inner layer (2) comprises at least three polyamides, at least one of said polyamides A, B and C is excluded.

Multilayer motor vehicle tube for conducting at least one fluid medium, wherein the tube comprises a fluid duct and a tube wall that surrounds the fluid duct. The tube wall is multilayered and comprises at least three layers, specifically having the following layer composition. An external layer is provided that consists of at least one polyamide, in particular of at least one aliphatic polyamide. Furthermore, an adhesion-promoting layer is provided and an internal layer consisting of at least one thermoplastic elastomer. The overall layer thickness d of the tube wall is from 0.3 to 3.0 mm.

Hoses include an inner tube, a reinforcement layer disposed outwardly from the inner tube, and a cover layer disposed outwardly from the reinforcement layer, where the cover layer and/or the inner tube include(s) a composition having a sustainable content. The composition includes one or more ethylene based sustainable polymers. The one or more ethylene based sustainable polymers is formed of ethylene monomer derived from one or more renewable sources. The one or more ethylene based sustainable polymers may be one or more of PVC sustainable polymer, EPDM sustainable polymer and EPR sustainable polymer.

A system for packing and assembling a flexible duct that includes a sleeve. The sleeve includes a tubular vapor barrier and an insulating layer within the vapor barrier and includes a central cavity. Further, the sleeve is radially compressed and rolled along an axial direction. The system also includes an air core sized to fit within the central cavity of the insulating layer. The air core includes a sheet that blocks fluid flow therethrough and a structural support coiled within the sheet and the air core is flattenable and not within the rolled sleeve.

A vacuum insulated structure including a tube having an outer wall, a jacket surrounding the tube to enclose an annular insulating space, the jacket having an end that terminates at the outer wall of the tube, a seal formed between the end of the jacket and the tube to preserve a vacuum within the insulating space, and a fitting affixed to one of the tube and the jacket for coupling the vacuum insulated structure to an external device. A method of making a vacuum insulated structure including forming a tube and a jacket, positioning the jacket over the tube to form an annular insulating space, with an end of the jacket being positioned adjacent to an outer wall of the tube to form a vent, causing air to escape through the vent, sealing the vent, and affixing a fitting to one of the tube and the jacket.

Techniques for implementing a pipe segment that includes a tubing inner barrier layer that defines a pipe bore through the pipe segment, a venting tubing annulus implemented around the tubing inner barrier layer, in which the venting tubing annulus includes a first solid material implemented to define a venting fluid conduit, a tubing intermediate barrier layer implemented around the venting tubing annulus, a reinforcement tubing annulus implemented around the tubing intermediate barrier layer, and a tubing outer barrier layer implemented around the reinforcement tubing annulus. The reinforcement tubing annulus includes a second solid material that is different from the first solid material and is implemented to define a reinforcement fluid conduit. Additionally, the venting fluid conduit facilitates venting fluid that permeates from the pipe bore through the tubing inner barrier layer out from the pipe segment before the fluid contacts the second solid material in the reinforcement tubing annulus.

A refrigerant hose has an innermost tube defining a lumen therein, and the innermost tube is based on one of a hydrogenated nitrile butadiene rubber (HNBR), an HNBR containing polymer blend, or a copolymer thereof, which is cured with a phenol-formaldehyde resin. The refrigerant hose may further include an optional permeation inhibiting layer which surrounds the innermost tube when incorporated, a reinforcing layer disposed outwardly from the innermost tube and the optional permeation inhibiting layer when this layer is used, and a cover layer disposed outwardly from the reinforcing layer. The innermost tube has a volume swell percentage of 10% or less when exposed to polyolester oil or polyalkylene glycol oil for 168 hrs @ 125° C. Additionally, the innermost tube is devoid of peroxide and may further be devoid added elemental sulfur, sulfur donors and/or additives containing sulfur within their molecular structures.

A system for packing and assembling a flexible duct that includes a sleeve. The sleeve includes a tubular vapor barrier and an insulating layer within the vapor barrier and includes a central cavity. Further, the sleeve is radially compressed and rolled along an axial direction. The system also includes an air core sized to fit within the central cavity of the insulating layer. The air core includes a sheet that blocks fluid flow therethrough and a structural support coiled within the sheet and the air core is flattenable and not within the rolled sleeve.