Abstract:
An elongated multi-layer tubing (10) is disclosed for connection to a motor vehicle system to handle fluids containing hydrocarbons. The tubing includes a first layer (14) disposed radially innermost and having an inner surface capable of prolonged exposure to a fluid containing hydrocarbons and an outer surface spaced a first predetermined radial thickness from the inner surface, the first layer (14) consisting essentially of an extrudable, melt-processible thermoplastic. The tubing (10) also includes a second layer (16) having a second predetermined radial thickness at most equal to the thickness of the first layer (14). The second layer (16) is uniformly and homogeneously connected to or bonded to the first layer (14) and consists essentially of an extrudable, melt-processible thermoplastic capable of sufficiently permanent laminar adhesion with the first layer (14) to prevent delamination during a desired lifetime of the tubing. At least one of the first and second layers (14, 16) is resistant to permeation by hydrocarbons. The tubing (10) includes a third layer (12) having a third predetermined radial thickness greater than the thickness of the first layer (14). The third layer (12) is capable of sufficiently permanent laminar adhesion to the second layer (16) to prevent delamination during said desired lifetime of said tubing. The third layer (12) is uniformly and homogeneously connected to or bonded to the second layer (16) and consists essentially of an extrudable, melt-processible thermoplastic. At least one layer of the tubing (10) is capable of dissipating electrostatic energy in a range between about 10 to 10 Ohm/cm .
Abstract:
A layered tubing (10) for use in a motor vehicle composed of a thick outer layer (12) having an inner and an outer face, the outer layer (12) made of an extrudable thermoplastic elastomer; a thin intermediate bonding layer (14) bonded to the inner face of the thick outer layer (12), the bonding layer (14) composed of an extrudable melt-processible thermoplastic capable of sufficiently permanent laminar adhesion with the thick outer layer (12); an interior layer (16) bonded to the intermediate bonding layer (14), the interior layer (16) composed of a fluoroplastic which is resistant to permeation by and interaction with short-chain aliphatic and aromatic compounds; and an innermost electrostatic dissipation layer (18).
Abstract:
An elongated fuel and vapor tube (10) suitable for conveying fluids containing hydrocarbons having a first layer (12) disposed radially innermost and having an inner surface capable of prolonged exposure to the hydrocarbon-containing fluid made up of a melt processible fluoroplastic terpolymer composed of a polyfluorinated alkylene, an alpha -fluoro-olefin and a fluorinated vinyl compound and a second layer bonded directly to the outwardly oriented face of the first layer. The second layer (14) is composed of a resinous thermoplastic material which is preferably a polyamide such as Nylon 12, Nylon 11, Nylon 6 or Nylon 6.6.
Abstract:
A multi-layer tube (10) comprises a metal tube (12) having an outer surface (13) and a zinc layer (14) bonded to the metal tube outer surface (13), wherein the zinc layer (14) is selected from the group consisting of zinc plating, zinc nickel alloys, zinc cobalt alloys, zinc aluminum alloys, and mixtures thereof. A surface treatment layer (16) is bonded to the zinc layer (14), wherein the surface treatment layer (16) is selected from the group consisting of a zinz/aluminum/rare earth alloy, phosphate, chromate and mixtures thereof. A first polymeric layer (18) is bonded to the surface treatment layer (16), wherein the first polymeric layer (18) is selected from the group consisting of a thermoplastic elastomer, an ionomer, a nylon, a fluoropolymer, and mixtures thereof. A second polymeric layer (22) is bonded to the first polymeric layer (18), wherein the second polymeric layer (22) is selected from the group consisting of a nylon, a thermoplastic elastomer, a fluoropolymer, and mixtures thereof. A process for manufacturing a multi-layer tubing (10) for conveying fluids in a vehicle system comprises the step of extruding multiple layers of a melt-processible thermoplastic to a pretreated metal tube (12) having an external surface (13) with at least a zinc based coating (14) and a sealant coating on top of the zinc based coating (14).
Abstract:
A multi-layer tube (10) suitable for use on motor vehicles composed of a cylindrical wall having an outer surface, and an inner surface essentially parallel to the outer surface. The cylindrical wall has a first region (26) having an essentially uniform cross-sectional diameter and a second region (28) which has a cross-sectional diameter differing from the diameter of the first region (26). The second region (28) has at least one convolution or corrugation (30) contiguously adjacent to the cylindrical wall of the first region (26). The cylindrical wall is made up of a thick flexible outer layer (12) having an inner and an outer face, composed of an extrudable melt-processible thermoplastic; a thin intermediate bonding layer (16) bonded to the inner face of the thick outer layer (12), composed of an extrudable melt-processible thermoplastic capable of sufficiently permanent laminar adhesion to the outer layer to prevent delamination during the desired lifetime of the tubing; and an interior layer (14) composed of an extrudable melt-processable thermoplastic which is capable of sufficiently permanent laminar adhesion to the intermediate bonding layer (16) to prevent delamination of the tubing during the desired lifetime. The thermoplastic material in the interior layer has an elongation value at break of at least 150 % and an ability to withstand impacts of at least 2 foot-pounds below about -20 DEG C. The inner layer has a thickness less than the thickness of the outer layer.