The present disclosure provides a flow device including a body disposed in an extrusion apparatus. The body is defined along a plane and has a first side and a second side. The second side is disposed opposite the first side. The flow device also includes a first face formed at the first side and a second face formed at the second side. The body has a thickness defined between the first face and second face. A plurality of feedholes is defined in the body between the first side and the second side. In addition, at least a portion of the first face or second face forms a curvature that extends outwardly from the plane.

A dosage device for extruding a monocomponent or a bicomponent polymeric product, particularly for an automatic machine for forming a spacer frame, includes a first dosage assembly and a separate second dosage assembly for the dosage and feeding of the product, which can be activated, in a first feeding step and in a third feeding step, alternately so that one of them provides continuity of flow to an extrusion nozzle while the other one is in the reloading step. The first and second dosage assemblies are activated, in a second swapping step that is intermediate with respect to the first and third feeding steps, simultaneously and jointly, one of them having a flow-rate ramp that passes from the steady-state value to zero and the other one complementarily having a flow-rate ramp that passes from zero to the steady-state value.

A process and associated system for creating color effects in extrudable material, such as plastic and metal for example, are presented. Flows of first and second viscous materials of respective colors are provided and then combined in a predetermined pattern to form a stream of combined viscous material. In a first aspect, the flow rate of the first viscous material is caused to vary over time in order to vary an amount of the first viscous material in the stream. In a second aspect, which may be used alone or in combination with the first aspect, the first and second viscous materials have distinct viscosities to reduce an amount of color blending between the first color and the second color in the stream of combined viscous material. A static mixer may then be used to apply a predetermined dividing, overturning and combining motion to the stream of combined viscous material to partially mix the first viscous material and the second viscous material, such that upon exiting the static mixer, the first material of the first color and the second material of the second color form a color pattern in the stream of combined viscous material. Sheets of extrudable material may be created using such process and used in the manufacturing of many different products including for example kayaks and stand-up paddle boards.

In one embodiment, a method of forming an extruded board includes mixing a resin and a foaming agent, melting the mixed resin and foaming agent to form a uniformly colored extrudate, differentially expanding voids formed from the foaming agent within the uniformly colored extrudate by passing the uniformly colored extrudate through a breaker plate, forming a board with the differentially expanded voids and uniformly colored extrudate, and forming lightened portions on an outermost surface of the formed board.

A method for producing an electrically conductive seamless tube includes (1) preparing an electrically conductive resin composition containing a thermoplastic resin and an electrically conductive filler, (2) preparing a cylindrical extruding die including a cylindrical slit, at least one circumferential distribution channel communicating with the slit and distributing the resin composition that is plasticized in a circumferential direction of the slit, and at least one lead-in path that leads the plasticized resin composition into the circumferential distribution channel, the lead-in path containing a line mixer; (3) introducing the plasticized resin composition into the lead-in path toward the circumferential distribution channel; (4) introducing the plasticized resin composition flowing through the lead-in path into the circumferential distribution channel toward the slit; and (5) introducing the resin composition flowing through the circumferential distribution channel into the slit and extruding the resin composition from an outlet of the slit into a cylindrical shape.

Techniques recycle plastics in multiple successive process steps. A polymer, preferably a recyclable material, is melted using a discharge extruder, filtered using a first filter device under a positive pressure atmosphere, filtered and degassed using a degassing device, and discharged using a discharge extruder. The degassing device has at least one filter element and a vacuum chamber with a negative pressure atmosphere for filtering and degassing purposes, wherein the plastic melt can be conducted into the negative pressure atmosphere of the vacuum chamber through the filter element.

Apparatus and methods for extruding plastic materials are disclosed. An exemplary apparatus comprises: a feeding portion; a melting portion in communication with the feeding portion and configured to transmit heat into material received from the feeding portion; and an output die in communication with the melting portion to permit extrusion of the material. The melting portion comprises: a melting barrel having an inner surface defining a melting chamber in communication with the feeding portion; and a melting insert inside the melting chamber. The melting insert comprises an outer surface in contact with the inner surface of the melting barrel where the outer surface comprises one or more open-ended channels formed therein. In some embodiments, the feeding portion and the melting portion may be thermally insulated from each other and a propeller of the feeding portion may be disposed entirely outside of the melting portion.

A process and associated system for creating color effects using extrudable material, such as plastic and metal for example, are presented. Flows of first and second viscous materials of respective colors are provided and then combined in a predetermined pattern to form a stream of combined viscous material. In a first aspect, the flow rate of the first viscous material is caused to vary over time in order to vary an amount of the first viscous material in the stream. In a second aspect, which may be used alone or in combination with the first aspect, the first and second viscous materials have distinct viscosities to reduce an amount of color blending between the first color and the second color in the stream of combined viscous material. A static mixer may then be used to apply a predetermined dividing, overturning and combining motion to the stream of combined viscous material to partially mix the first viscous material and the second viscous material, such that upon exiting the static mixer, the first material of the first color and the second material of the second color form a color pattern in the stream of combined viscous material. Sheets of extrudable material may be created using such process and used in the manufacturing of many different products including for example kayaks and stand-up paddle boards.

A method for directly preparing a foamed polylactic acid (PLA) product from a PLA melt includes PLA melt preparation, feeding, and two-stage extrusion. In the two-stage extrusion, a pressure at an outlet of a first-stage twin-screw extruder is 15 MPa to 17 MPa, a PLA melt is fed at a rate of 250 kg/h, a foaming additive is fed at a rate of 7.5 kg/h to 10 kg/h, and a foaming gas is fed at a rate of 2.8 L/h to 7.5 L/h. The method can ensure both foamability and quality of a material and reduce more than of energy consumption; and an obtained product has an adjustable foaming rate of 3 to 25, a crystallinity of 40.3% to 48.5%, a tensile strength of 8.7 MPa to 19.6 MPa, and an apparent density of 0.05 g/cm.sup.3 to 0.4 g/cm.sup.3.

A method of manufacturing bulked continuous carpet filament from a plurality of polymer flakes comprises: (1) providing an extruder; (2) melting and purifying the plurality of polymer flakes into a polymer stream using the extruder; (3) providing a static mixing assembly downstream of the extruder; (4) adding a first liquid colorant to a center of the polymer stream at a first location before the static mixing assembly or along a length of the static mixing assembly; (5) adding a second liquid colorant to the polymer stream at a second location before the static mixing assembly or along a length of the static mixing assembly; (6) using the static mixing assembly to mix the polymer stream with the first and second liquid colorant to create a colored polymer stream; and (7) forming the colored polymer stream into bulked continuous carpet filament.