A screw extruder which extrudes a kneaded material includes a screw having a helical flight provided on an outer peripheral surface of a shaft portion thereof, and a chamber housing the screw. In the screw extruder, a flight thickening portion is provided at a part which is a tip portion of the flight and is on the reverse side of a rotation direction of the flight.

In kneading rotors, a twist angle of long wing constituting kneading wings is between 38 degrees and 53 degrees inclusive. The long wing includes, between the long wings and an inner surface of a casing, wing tops configured to form, along a wing longitudinal direction, a first tip clearance, and a second tip clearance narrower than the first tip clearance in width. A central angle of the long wing forming the second tip clearance is between 5 degrees and 10 degrees inclusive.

Provided are a quality inspection method and a quality inspection system for unvulcanized rubber material. A final dielectric constant measurement device detects the dielectric constant of a final rubber material in which a compounding agent of predetermined type is mixed with unvulcanized rubber, and a calculator calculates a compounding ratio of the compounding agent to the final rubber material based on the detected dielectric constant, determines whether or not the calculated compounding ratio is in a preset compounding reference range, displays a determination result on a monitor, and adjusts a ratio of the compounding agent fed into an extruder to the unvulcanized rubber such that the calculated compounding ratio is within the compounding reference range.

A method for manufacturing wet rubber masterbatch obtained from raw materials in the form of at least filler, dispersion solvent, and rubber latex solution, includes an operation in which the rubber latex solution is mixed and coagulated with a slurry solution containing the filler and the dispersion solvent to manufacture a filler-containing rubber coagulum; and a heating operation in which a single-screw extruder is used to carry out dewatering, drying, and plasticization of the filler-containing rubber coagulum in a single operation. The method satisfies conditions: 0.02≤C/(A×B)≤0.15, where A indicates, for a portion of the screw which is located at the dewatering portion, the pitch volume (mm.sup.3), B indicates rotational speed (rpm) of the screw, and C indicates feed volume per minute (mm.sup.3/min) of the filler-containing rubber coagulum which is fed into the single-screw extruder.

A method for stacking a ply (50) which is transferred from a rubber mixing system to a stacking system (100) comprises the steps of transferring the ply (50) to a stacking head (120) of the stacking system (100); passing the ply (50) to a motorized belt (110) of the stacking system (100), the motorized belt (110) being able to turn in both directions and being able to move in translation, and the motorized belt (110) being situated between the stacking head and a pallet (P) chosen from a pallet (P) with edges and a pallet (Q) without edges; and setting the motorized belt (110) into movement in translation so as to move along a path such that the motorized belt (110) receives the ply (50) from the stacking head (120) and makes a downstream end (50b) of the ply (50) to be stacked accessible in order to connect it to an upstream end (52a) of a ply (52) of a successive pallet and form a butt joint between the plies (50, 52).

Method for producing a thermoplastic molding compound (F) in an extruder, which has at least one screw having an outside diameter (D), wherein a thermoplastic component (TP) containing at least one thermoplastic polymer, a component (C) containing a graft polymer based in particular on butadiene and/or acrylate, and optionally a component (Z) containing additives are heated to a temperature of 200° C. to 280° C., melted and mixed by supplying thermal energy in a melting section (S) and/or in at least one mixing section (M) such that the thermoplastic molding compound (F) is formed, and the thermoplastic molding compound is subsequently degassed in a degassing zone (E) of the extruder, wherein an absolute pressure (P1) of less than 2 bar is set in this zone, and after the degassing the molding compound (F) is conveyed to a melt pump (SP) by screw elements, wherein the total length of the screw elements of a conveying path (FS) from the degassing opening (O) to the melt pump (SP) is less than five times the outside diameter (D) of the at least one screw.

It is described an apparatus for the extrusion and mixing of plastic materials, for example rubber-based and silicone-based materials, comprising a dump extruder body whereon two conical screws (2) converging towards an extrusion die (3) suitable for being occluded by closing means (4) are mounted, the conical screws (2) being accommodated within a low-pressure compounding chamber (1) and within a pair of converging conical channels also defining a high-pressure chamber (2′), said low-pressure chamber (1) corresponding to an upstream area with respect to an extrusion direction, wherein said high-pressure chamber (2′) and/or said low-pressure chamber (1) accommodate a presser body (5, 5′, 6), defining a movable wall suitable for causing a controlled change in the volume of the respective chamber (1, 2′).

Liquid mixing processes are provided for producing an elastomeric composition as a function of a selected elastomeric composition recipe. A system (10) is also provided for the production of an elastomeric composition according to the disclosed liquid mixing processes.

The invention relates to a method for homogenously incorporating filler into a self-adhesive compound, in particular a thermally crosslinkable self-adhesive compound, based on non-thermoplastic elastomer in a continuously working unit with a filling part and a compounding part. The self-adhesive compound contains at least one solid component, at least one liquid component, and at least one filler, and the method has the following steps: (a) feeding at least part of the at least one solid component, such as the non-thermoplastic elastomer in particular, and optionally part of the at least one liquid component to the filling part; (b) transferring the components of step (a) from the filling part to the compounding part; (c) optionally adding additional solid components or additional parts of the solid components to the compounding part; (d) adding the at least one liquid component to the compounding part if the liquid component was not already added to the filling part in step (a); (e) producing a homogenous self-adhesive compound in the compounding part; and (f) discharging the self-adhesive compound. The invention is characterized in that at least part of the at least one filler is pre-dispersed into at least one dispersion liquid in a separate unit and the dispersion obtained in this manner is added to the compounding part. The method prevents high sheering or frictional energies while introducing the filler into the compounding part of the continuously working unit and thus allows the use of temperature-sensitive components, such as temperature-sensitive chemical crosslinking agents in particular.

The invention relates to a rubber blend, to a sulfur-crosslinkable rubber mixture comprising the rubber blend and to a vehicle tire comprising such a rubber mixture. The rubber blend comprises at least one solution-polymerized diene polymer A of high molecular weight and at least one solution-polymerized polymer B of low molecular weight, wherein at least one of polymers A and B has been functionalized at the chain end and/or along the polymer chain and/or at a coupling site with at least one group selected from epoxy groups, hydroxyl groups, carboxyl groups, silane sulfide groups, amino groups, siloxane groups, organosilicon groups, phthalocyanine groups and amino group-containing alkoxysilyl groups and wherein the rubber blend includes 35 to 100 phr (based on the at least one solution-polymerized diene polymer A of high molecular weight), preferably 35 to 70 phr, of the at least one solution-polymerized polymer B of low molecular weight.