Hermann Berstorff Maschinenbau Gmbh

Atecs Mannesmann Ag

Foley & Lardner, Schwartz Et Al.

Gerd Capelle

Heinz Brinkmann

Gunther Meier

Dietmar Anders

Klaus Bellmer

Dieter Mayer

Holger Schaarschmidt

Markus-Michael Wolff

Martin Preuss

Martin Preuß

An extruder plant includes a worm extruder having a reduced length and including only a feed zone of the extruder plant and a gearwheel extruder connected downstream of the worm extruder and including a plasticizing and pressure build-up zone of the extruder plant.

Extruder plant with worm extruder and gearwheel extruder

The invention is directed to a method and an arrangement for continuously producing a rubber base compound and a rubber end compound in a single stage for vehicle tires, drive belts, conveyor belts as well as for industrial rubber products. The rubber base compound and the rubber end compound are produced continuously in one and the same mixing arrangement which includes a twin-screw extruder.

Method and apparatus for the single-stage continuous production of a

The present invention relates to an apparatus for producing a controllable, uniform conveying pressure for processing highly viscous, temperature sensitive rubber or thermoplastics, consisting of two rotating conveying elements that form a toothlike sealing profile and are arranged on shafts in a housing. The root diameter of the conveying elements more or less corresponds to the diameter of the shaft sections that are axially adjacent to the conveying elements on either side and form bearing surface therefor. The radial faces of the conveying elements are thus avoided and so are the usually rather difficult sealing problems at these faces. By additionally providing either the shaft sections or the surrounding housing parts with return channels the channel volume of which decreases in the conveying direction, the axial sealing capacity of the gear pump is improved considerably.

Apparatus for producing a controllable, uniform conveying pressure for

The invention is directed to a method and an arrangement continuously producing a rubber base compound and a rubber end compound in a single stage for vehicle tires, drive belts, conveyor belts as well as for industrial rubber products. The rubber base compound and the rubber end compound are produced continuously in one and the same mixing arrangement which includes a twin-screw extruder.

Method and arrangement for the single-stage continuous production of a

The invention relates to an apparatus for producing a controllable, uniform conveying pressure for processing highly viscous, temperature sensitive rubber or thermoplastics material. The apparatus includes two rotating conveying elements that conjointly form a tooth-like sealing profile and that are arranged on respective shafts in a housing. The root circle diameters of the conveying elements more or less correspond to the diameters of the shaft sections axially adjacent to the conveying elements. For this reason, the radial end faces of the conveying elements are avoided and so are the difficult sealing problems which would otherwise be present at these end faces. The shaft sections adjacent the conveying elements guide and keep the toothed profiles in alignment with each other as they rotate to convey the material.

Apparatus for producing a controllable uniform conveying pressure for

An exact distance between the rotating knives and the stationary die plate of a pelletizer can be set and maintained during the entire pelletizing process. The drive shaft for the cutting beams and cutting knives can be heated or cooled and is supported on the knife side in a mobile bearing. As a result of the heating/cooling of the shaft, the shaft is allowed to extend through the mobile bearing in the direction of the knife head, whereby the distance between the die plate and the cutting knives rotating above the plate can be adjusted precisely and within the My range.

Pelletizer with cutting knife control

A process for the continuous production of a rubber compound in a twin-screw extruder is disclosed that improves the dispersion of carbon black in the extrudate while reducing the specific energy requirements of the extrudate. Rubber is fed into the extruder together with a processing aid and masticated up to a temperature of 120.degree. C. to 180.degree. C. Subsequently, a first part of carbon black representing preferably 40% to 80% of the whole quantity of carbon black is fed into the heated extrudate. Afterwards, plasticizing oil is added to the extrudate before the second remaining carbon black part is fed and incorporated into the extrudate at a temperature of 120.degree. C. to 180.degree. C. The whole compound is then cooled, a crosslinking agent is added, and the compound is homogenized and extruded.

Process for the continuous production of rubber compounds in a

An extruder for poorly miscible extrudates which includes a pin-lined barrel section and a transfer mixing section used together. Restricting pins are arranged in the transfer mixing section in the region of the greatest barrel channel volume and permit universal use of the extruder with respect to the extrudate. The combination of the two mixing systems allows in a surprising way an increase in the material throughput of 60% to 100% with the mixing quality remaining the same and a halving of the drive torque. Due to a constant number of channels of the barrel channels and screw channels, the number of barrel flights and screw flights remains independent of the channel cross-sectional area of barrel and screw. A helical barrel groove in the feed zone of the extruder barrel additionally improves the mixing quality of the extrudate and the output of the extruder.

Extruder for poorly miscible extrudates

A process and an apparatus for optimal operation of a high-speed extruder in which a pin-lined barrel section and a Transfermix section, both known per se but separately used, are utilized together in an extruder. The combination of these mixing systems allows in a surprising way an increase in the material throughput of 60% to 100%, with the mixing quality remaining the same and the drive torque being halved. The static extrudate pressure can be further increased by arranging an adjustable restriction device downstream of the extruder screw, thereby permitting a further increase in the output rate.

Process and apparatus for optimal operation of a high-speed extruder

A pin transfer extruder is provided, wherein the pin-barrel and transfer mixing sections, which are known per se and have only been used individually hitherto, are jointly used in one extruder. Throttle pins, which are disposed in the transfer mixing section in the region of the greatest housing thread volume, permit universal use of the extruder in respect of the extruded material. The combination of both mixing systems permits the throughput of material to be increased in a surprising manner by 60% to 100%, while a constant mixing quality is maintained and the driving torque is halved. The number of the housing and screw flights remains independent of the cross-sectional area of the housing and screw threads because the number of housing and screw threads is constant.

High performance extruder with a constant number of threads in the inlet

A pin transfer extruder is provided, wherein the pin-barrel and transfer mixing sections, which are known per se and have only been used individually hitherto, are jointly used in one extruder. Throttle pins, which are disposed in the transfer mixing section in the region of the greatest housing thread volume, permit universal use of the extruder in respect of the extruded material. The combination of both mixing systems permits the throughput of material to be increased in a surprising manner by 60% to 100%, while a constant mixing quality is maintained and the driving torque is halved.

Pin transfer extruder

A single-screw degassing extruder for thermoplastic plastics materials and rubber is provided, wherein the pin-barrel and transfer sections, which are known per se and have only been used individually hitherto, are jointly used in one extruder. Throttle pins, which are disposed in the transfer section in the region of the greatest housing thread volume, permit universal use of the extruder in respect of the extruded material or combinations of extruded material and stripping agent, since the mixing efficiency of the extruder and the pressure of the extruded material upstream of a degassing opening in the extruder are thereby advantageously controllable.

Degassing extruder

A high-performance extruder is provided, wherein the pin-barrel and transfer mix mixing sections, which are known per se and have only been used individually hitherto, are jointly used in one extruder. The combination of both mixing systems permits the throughput of material to be increased in a surprising manner by 60% to 100%, while a constant mixing quality is maintained and the driving torque is halved.

High-performance extruder

In an extrusion device of the type which has a screw rotating in a housing and which has a feed section in which a feed roller, cooperating with the screw, is provided, a stripper blade is used to remove the fed material from the feed roller. The present invention provides a method and an apparatus for maintaining the net force acting on the stripper blade to direct it towards the feed roller constant. To achieve this, the force of the fed material which acts in a direction tending to move the feed roller and the extrusion screw apart is measured. An opposing force is applied to the stripper blade in dependence upon the magnitude of the measured force. By so doing, the net force directing the stripper blade towards the feed roller is maintained constant.

Method of maintaining the force of a stripper blade on an extruder feed

An extrusion head for processing rubber or thermoplastic plastics material including a housing flange-mountable on a screw extrusion device. The head further including an inlet region for receiving material from the extrusion device and for receiving the downstream end of the screw, the inlet leading into a flow channel portion and a nozzle outlet which receives the material from the flow channel for extrusion in the form of a shaped profile. A sealable air discharge device is disposed in the flow channel portion to remove air bubbles, particularly that which is formed during the start up phase of the extrusion downstream of the downstream end of the screw.

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Langenhagen, Germany

Gerd Capelle