Abstract: A method for producing a foamed extrudate comprises a device containing a main melting device and an auxiliary melting device. A first melt is generated in the main melting device, a second melt is generated in the auxiliary melting device from a meltable starting material. At least one reactive additive is added to the meltable starting material, wherein the at least one reactive additive being selected from the group consisting of a chemical blowing agent and an active nucleating agent is mixed in the auxiliary melting device with the second melt, so that an additive-containing second melt is obtained in the auxiliary melting device which is added to the first melt.

Abstract: A system for metering a liquid or gaseous medium comprises a pressure control valve and a flow sensor, the pressure control valve and the flow sensor forming a closed control circuit. The required metering quantity can be adjusted by controlling the metering pressure by means of the pressure control valve.

Abstract: A system for metering a liquid or gaseous medium comprises a pressure control valve and a flow sensor, the pressure control valve and the flow sensor forming a closed control circuit. The required metering quantity can be adjusted by controlling the metering pressure by means of the pressure control valve.

Abstract: A mixer structure for a film die for a polymer melt includes multiple web elements. The web elements include a first web element and a second web element. The first web element and the second web element include at least an end, which is connected to a base. A film die includes a first tool element, a second tool element, and a flow channel for the polymer melt extending between the first tool element and the second tool element. The mixer structure is arranged in the flow channel. The mixer structure is held in at least one of the tool elements by a holding element.

Abstract: A mixer structure for a film die for a polymer melt includes multiple web elements. The web elements include a first web element and a second web element. The first web element and the second web element include at least an end, which is connected to a base. A film die includes a first tool element, a second tool element, and a flow channel for the polymer melt extending between the first tool element and the second tool element. The mixer structure is arranged in the flow channel. The mixer structure is held in at least one of the tool elements by a holding element.

Abstract: A method for cooling a foamed ribbon-shaped extrudate strand (3) is performed in a plant which comprises an extruder (8), a die (1), a vacuum cooling device (2) and a cooling drum. A polymer melt containing a blowing agent is produced in the extruder (8). The extrudate containing the blowing agent is guided to the die (1), whereby the die has an opening (7), through which a ribbon-shaped extrudate strand (3) is produced which foams in or after the die (1) to a foamed ribbon-shaped extrudate strand (13). The ribbon-shaped plastic foamed or foamable extrudate strand (13) is cooled first by a static vacuum cooling device (2, 25, 26), so as to obtain a precooled foamed ribbon-shaped extrudate strand (23) and the precooled foamed ribbon-shaped extrudate strand (23) is guided over a cooling drum (40, 41, 42). The precooled foamed ribbon-shaped extrudate strand (23) is in contact with the cooling drum over a wrap angle of at least 20°, such that the precooled foamed ribbon-shaped extrudate strand (23) is cooled.

Abstract: The apparatus for the production of foams includes an extrusion device for the plastification of a polymer melt, a heat exchanger for the cooling of the polymer melt, and also a connection piece for the connection of the extrusion apparatus to the heat exchanger. The connection piece contains a metering device for the introduction of a foaming agent into the polymer melt.

Abstract: A method for the manufacture of a molding composition from a raw material melt which is charged with an additive includes the steps: charging a conveyor apparatus with a raw material which includes a liquid or gooey pasty composition or a granulate; converting the raw material into a raw material melt by heat supply to the raw material; charging the raw material melt with an additive; mixing of the raw material melt with the additive to produce a molding composition; and discharging the molding composition from the conveyor apparatus. The charging of the raw material melt with the additive takes place through a metering device which is arranged in a passage section of the conveyor apparatus and/or subsequent to the conveyor apparatus with the raw material melt flowing through and/or around the passage section. The metering device includes at least one metering element which is arranged in a recess of the passage section.

Abstract: The apparatus for the production of foams includes an extrusion device for the plastification of a polymer melt, a heat exchanger for the cooling of the polymer melt, and also a connection piece for the connection of the extrusion apparatus to the heat exchanger. The connection piece contains a metering device for the introduction of a foaming agent into the polymer melt.

Abstract: A metering device for the feeding of additives to a gooey fluid or a pasty composition, in particular to a plastic melt, includes a passage section receiving the fluid and which contains at least one metering element for the injection of an additive into the plastic melt. The passage section has a recess for the reception of the metering element that is bounded at all sides by the passage section. The metering element is made of a porous structure or with a capillary structure for the passage of the additive.

Abstract: A method for the manufacture of a molding composition from a raw material melt which is charged with an additive includes the steps: charging a conveyor apparatus with a raw material which includes a liquid or gooey pasty composition or a granulate; converting the raw material into a raw material melt by heat supply to the raw material; charging the raw material melt with an additive; mixing of the raw material melt with the additive to produce a molding composition; and discharging the molding composition from the conveyor apparatus. The charging of the raw material melt with the additive takes place through a metering device which is arranged in a passage section of the conveyor apparatus and/or subsequent to the conveyor apparatus with the raw material melt flowing through and/or around the passage section. The metering device includes at least one metering element which is arranged in a recess of the passage section.

Abstract: The manufacture of foamed polymer trim parts making use of physical blowing agents requires the diffusion and sorption of the blowing agent in the polymer melt. Said diffusion and sorption are achieved by intensive mixing. Therefore a statical mixing device is enclosed in a pressure chamber, which comprises a hollow porous cylinder, which has a surface suitable for contacting the melt with the blowing agent. The protrusions extending at least partially into the melt flow cause a multiple reorganisation of the polymer melt, which leads to thorough mixing and shortens the diffusion path. The statical mixing device, which may be of modular construction, increases mass transport and mixing by a small modification of a conventional injection molding machine.

Abstract: Foamed molded articles can be produced during an injection molding process, among other things, by utilizing physical blowing agents. Existing technologies differ to the greatest possible extent in the manner how the blowing agent is introduced into the melt. One possibility is to supply the blowing agent via mixing elements (9) from porous or permeable material that are provided across the screw piston (1) and which by means of a suitable blowing agent input unit load and homogeneously charge the melt with blowing agent during the metering phase of the polymeric material. The resulting single phase polymer/blowing agent mixture, when injected in to an injection mold tool, produces due to a reduction in pressure, a foam-textured part.

Abstract: The injection molding machine comprises a screw plunger (3), which rotates inside an injection unit (2), wherein the screw plunger (3) has, downstream from a metering zone a porous or permeable section (16) which can be charged with a physical expanding agent via an expanding agent feed device (18) in the screw shaft of the screw plunger (3) and which two-dimensionally introduces the expanding agent into the melt flow for molding of foamed shaped parts made of polymeric materials in an injection molding machine by an injection molding method.

Abstract: Foamed molded articles can be produced during an injection molding process, among other things, by utilizing physical blowing agents. Existing technologies differ to the greatest possible extent in the manner how the blowing agent is introduced into the melt. One possibility is to supply the blowing agent via mixing elements (9) from porous or permeable material that are provided across the screw piston (1) and which by means of a suitable blowing agent input unit load and homogeneously charge the melt with blowing agent during the metering phase of the polymeric material. The resulting single phase polymer/blowing agent mixture, when injected in to an injection mold tool, produces due to a reduction in pressure, a foam-textured part.

Abstract: The manufacture of foamed polymer trim parts making use of physical blowing agents requires the diffusion and sorption of the blowing agent in the polymer melt. Said diffusion and sorption are achieved by intensive mixing. Therefore a statical mixing device is enclosed in a pressure chamber, which comprises a hollow porous cylinder, which has a surface suitable for contacting the melt with the blowing agent. The protrusions extending at least partially into the melt flow cause a multiple reorganisation of the polymer melt, which leads to thorough mixing and shortens the diffusion path. The statical mixing device, which may be of modular construction, increases mass transport and mixing by a small modification of a conventional injection molding machine.

Abstract: The invention relates to an injection molding machine for the injection molding of foamed shaped parts made of polymeric materials in an injection molding method by introducing a physical expanding agent into the melt flow. The injection molding machine comprise a screw plunger (3), which rotates inside an injection unit (2). According to the invention, the screw plunger (3) has, downstream from a metering zone a porous or permeable section (16) which can be charged with the expanding agent via an expanding agent feed device (18) in the screw shaft of the screw plunger (3) and which two-dimensionally introduces the expanding agent into the melt.