Patent classifications
B29B7/488
TWIN-SCREW MIXING AND EXTRUSION MACHINE WITH MOBILE ELEMENTS
A mixing and extrusion machine (10) has a converging conical twin-screw mixer (12) with a fixed frame (14) that supports sleeves (16) in which two screws (18) are mounted at an angle between an opening (22) arranged upstream of the sleeves, where an introduction hopper (24) of the machine (10) feeds the screws, and an outlet (25) arranged downstream of the sleeves, where the mixer discharges the mixture at the end of a mixing cycle. At least one mobile sleeve (34) is disposed towards the outlet, each mobile sleeve with a support surface (34a) of a predetermined surface area (34a) according to an elasticity of the mixture, and each mobile sleeve having one or more mobile elements that move by a linear movement with respect to the outlet in order to adjust a predetermined space between the sleeves and the screws.
Method and facility for producing polylactide (PLA) from a lactide mixture by means of polymerization
A method and a facility produce polylactide (PLA) by polymerization, in which a lactide mixture is mixed with at least one catalyst, is introduced into a modular planetary roller extruder and the finished PLA is then removed. The lactide mixture continuously passes through segments of the extruder. The course of the reaction is measured and controlled in the segments in a targeted manner such that the temperature can be set by heating and/or cooling. The pressure can be variably set depending on pressure values to be checked by a controllable gas extraction and/or a controllable extruder speed and/or static variability of the planetary rollers and/or a variable metering speed of the lactide mixture and/or a variable mixing ratio of the lactide mixture. Flammable gas is removed in an explosion-protected zone in a partial region of the extruder. Additives are introduced into the extruder during the rolling process.
Twin screw extruder
A twin screw extruder (10) for producing a fiber-reinforced resin composition, which is obtained by charging the extruder with a thermoplastic resin and reinforcing fibers in roving form and the reinforcing fibers being fibrillated/cut and being dispersed/kneaded into the thermoplastic resin, comprises: a plate-shaped blade (15), which protrudes from the inner surface of a cylinder (11) and faces a screw (20) and the longitudinal direction of which faces the axial direction of the cylinder; and a height adjustment means (16) for adjusting the gap between the blade (15) and the screw (20).
Continuous compounding systems and methods of use
Continuous compounding systems include a feeding section and a compounding section. Method for compounding or mixing solid matter and liquid matter include providing a continuous compounding system, adding matter to the continuous compounding system, and mixing or compounding the matter.
Vacuum-assisted co-extrusion of flexible fibres and the moldable thermoplastic composites produced
A composite and method for producing the composite by incorporating wood or wood pulp fibres with a suitable thermoplastic polymer and coupling agent are described. Homogeneous, void-free transparent/translucent thermoplastic materials in the form of pellets, films or three-dimensional moldable products are produced. The wood pulp fibres can be discrete natural fibres, and flexible assemblies of nano to micro elements, e.g., assemblies of aggregated carbon nanotubes. It is also possible to use our vacuum-assisted co-extrusion process to produce hybrid composites comprising the wood pulp fibre and a further rigid fibre, like glass or carbon fibres, and a flexible fibre or fibrillar network, like cellulose fibres or cellulose filaments. The thermoplastic resin can be, but not limited to, polyolefins, like polypropylene or polyethylene, or polyesters, like polylactic acid, or co-polymers, like acrylonitrile-butadiene-styrene terpolymer.
Method for producing thermally crosslinkable polymers in a planetary roller extruder
A method for producing thermally crosslinkable polymers in a planetary roller extruder is presented. The planetary roller extruder has a filling part and a compounding part made of a roller cylinder region that comprises at least two, preferably at least three coupled roller cylinders, planetary spindles of which are driven by a common central spindle. The polymers are supplied in a plasticized state. The filling part is supplied with a vacuum. The flow temperatures of the central spindle and the at least two roller cylinders under a vacuum are set such that the polymers to be degassed remain in the plasticized state. One or more liquids, such as thermal crosslinkers, crosslinking accelerators, dye solutions, or dye dispersions, are metered to the plasticized polymers downstream of the vacuum degassing, preferably in a continuous manner. Finally, the resulting mixture is directly supplied to a coating assembly.
Extruder screw having paths within the screw, extruder, and extrusion method
An extruder screw conveying raw materials while kneading them includes a screw main body, conveyance portions, barrier portions, and paths. The conveyance portions convey the raw materials in an axial direction. The paths each include an entrance and an exit. The raw materials, the conveyance of which is limited by the barrier portions, flow in from the entrance. The raw materials flowing in from the entrance flow through the paths in the same direction as a conveyance direction of the conveyance portions. The exit is opened in the outer circumferential surface of the screw main body at a position outside the conveyance portions in which the entrance is opened.
Continuous methods of making fiber reinforced concrete panels
Continuous method including mixing water and cementitous powder to form slurry; mixing the slurry and reinforcement fibers in a single pass horizontal continuous mixer to form fiber-slurry mixture, the mixer including an elongated mixing chamber having a reinforcement fiber inlet port, and upstream of the fiber inlet port is an inlet port to introduce water and cementitous powder together as one stream or at least two inlet ports to introduce water and dry cementitous powder separately as separate streams into the chamber, a rotating horizontal shaft/s within the chamber, part of the chamber for mixing the fibers and slurry and moving the fiber-slurry mixture to a mixture outlet; discharging the fiber-slurry mixture from the mixer outlet; forming and setting the fiber-slurry mixture on a moving surface; cutting the set mixture into fiber reinforced concrete panels and removing the panels from the moving surface.
EXTRUDER SCREW HAVING PATHS WITHIN THE SCREW, EXTRUDER, AND EXTRUSION METHOD
A conveyance portion, a barrier portion, and a path are provided at places of a portion of a screw main body in which a kneading portion is provided. In at least one of the places, an entrance is opened to cause raw materials, conveyance of which is limited by a barrier portion to increase pressure on the raw materials, to flow in. The raw materials flowing in from the entrance flow through the path in the opposite direction to a conveyance direction of the conveyance portion. An exit is opened in an outer circumferential surface of the screw main body at a position outside the conveyance portion in which the entrance is opened.
MULTI-SHAFT PREPARATION UNIT FOR PLASTIC MELTS
A multi-shaft preparation unit for plastic melts, having an extruder housing with an enclosed treatment chamber in its interior, and at least one rotor body shaft mounted rotatably in the treatment chamber and a sealing and guiding body with multiple recesses, in each of which a satellite screw is mounted. The multi-shaft preparation unit has a drive unit in which a gearing unit is arranged outside the extruder housing between a drive motor and the treatment chamber and is connected to the drive shaft sections of the rotor body shaft and of the satellite screws which lead out of the treatment chamber of the extruder housing. A separating device for decoupling a flow of fluid and/or heat emanating from the treatment chamber is provided between the extruder housing and the gearing unit, through which the drive shaft ends of the rotor body shaft and of the satellite screws pass.