The invention relates to an extrusion-blow-molded fuel tank (1) of thermoplastic material comprising a tank wall of a composite of various layers obtained in various production operations, at least one first layer comprising at least one shell-shaped supporting shell (8) and a second layer of a thermoplastic material forming an adhesive bond with the supporting shell (8), and the supporting shell (8) having a greater strength than the second layer. The supporting shell (8) forms an inner layer of the tank and the second layer forms an outer skin of the tank, two supporting shells within the tank forming a supporting cage or a supporting housing.

The first aspect of the present invention provides a foamed structure, comprising: a first foamed body extending in a first direction; a second foamed body extending in the first direction and facing the first foamed body with a gap interposed therebetween; and a reinforcement disposed in the gap between the first foamed body and the second foamed body, the reinforcement having an elongated shape, wherein the first foamed body has a portion overlapping with the second foamed body in the first direction view.

A process of producing a hollow resin-molded article includes: arranging covers on inner walls of mold halves, the covers having shapes corresponding to the inner walls; introducing a pair of sheets of thermoplastic resin each facing the cover arranged on the inner wall of a corresponding mold half; blowing air into a space between the sheets to cause the sheets to respectively contact the covers arranged on the inner walls, and thereby fusion-welding the sheets to the covers; and closing the mold halves; and cooling down the covers and the sheets in a state where the mold halves are closed. In the step of arranging, there are uncovered portions of the inner walls that are not covered by the cover. In the step of closing, there are mold contact portions of the sheets that respectively contact the uncovered portions directly and the mold contact portions are fusion-welded to each other in an overlapping manner.

An article enclosing at least one built-in fitment component in the form of a hollow body of thermoplastic material. The hollow body is preferably in the form of a fuel tank. The built-in fitment component is pressed against the inside wall of the article while still plastic so that the plastic material of the hollow body penetrates through at least one recess or opening of the built-in fitment component and flows therebehind.

A method for manufacturing a plastic fuel tank including: a) inserting a plastic parison including two distinct parts into an open two-cavity mold; b) inserting a core, bearing at least part of a reinforcing element configured to create a link between the two parison parts, inside the parison; c) pressing the parison firmly against the mold cavities, for example by blowing through the core and/or creating suction behind the cavities; d) fixing the part of the reinforcing element to at least one of the parison parts using the core; e) withdrawing the core; f) closing the mold, bringing its two cavities together to grip the two parison parts around their periphery to weld them together; g) injecting a pressurized fluid into the mold and/or creating a vacuum behind the mold cavities to press the parison firmly against the mold cavities; and h) opening the mold and extracting the tank.

A twin sheet core structure made up of two sheets of plastic that have been thermoformed to define arrays of cavities having floors opening to surfaces defined by orthogonally intersecting ribs wherein the sheets are fused together to form a single structure with hollow areas between sheets.

Provided is a duct that does not cause defective molding and has a highly sound absorption inner surface which can effectively suppress noise. A duct includes a tubular duct main body and a sound absorption member disposed on the inner surface of the duct main body. The duct has at least one of configurations (1) to (3): (1) the duct main body has a sandwiching part having a pair of opposite wall surfaces, and a side edge of the sound absorption member is sandwiched between the wall surfaces of the sandwiching part; (2) the sound absorption member is pasted to the inner surface of the duct main body with a resin film therebetween; and (3) the sound absorption member and duct main body have parts which are not fused to each other.

The invention relates to a method for producing a tank from thermoplastic material, comprising the following method steps: extruding or providing a hose-like parison composed of plasticized thermoplastic material, and dividing and spreading the parison into two areal extrudate webs, or extruding or providing two parisons in web form, laying-in and molding the parisons in recesses of a multi-part blow-molding tool using differential pressure, wherein the recesses of the blow-molding tool delimit a mold cavity, punching out, or cutting out in a circular shape, at least one opening in at least one shell-like intermediate product, wherein the opening is produced by way of a punching or cutting tool which penetrates through a wall of one of the shell-like intermediate products, wherein in a second separate method step, a first attachment element of a line connection or of a line arrangement is welded, at the mold cavity side, to the wall of the shell-like intermediate product, in such a way that an encircling weld collar of the first attachment element sealingly surrounds the opening, joining the shell-like intermediate products to form a tank, and removing the tank from the blow-molding tool, and connecting a second attachment element, which is complementary to the first attachment element in the context of a plug-type connection, to the first attachment element, wherein the plug-type connection is produced within the contour of the tank as defined by the tank wall.

A hollow container producing device for producing a hollow container using a pair of parison sheets is provided. The hollow container producing device includes a pair of molds; an intermediate frame to be clamped to the pair of molds; and a transport unit that carries the intermediate frame and a pair of parison sheets to a position between the pair of molds, with the pair of parison sheets being respectively held on opposite sides of the intermediate frame.

In a method for producing a pipe made of a fiber-reinforced thermoplastic material, two workpieces of the material are provided. The workpieces are introduced into a tool having a core and two part molds surrounding the core. The workpieces are heated and shaped between the core and the part molds to give a structural part of the pipe. The core is removed from the structural parts, the structural parts being held on the part molds, and joining regions of the structural parts are oriented towards one another. The structural parts are joined to one another in the joining regions to form the pipe. The pipe is released from the part molds, wherein the part molds are moved away from one another after shaping in order to remove the core, and are then moved back together in order to orient the structural parts towards one another.