A self-cleaning dosing apparatus includes a material hopper for containing pellets of material, a feed screw, a first material outlet through which pellets of material fall by gravity onto a first end of the feed screw for the feeding of pellets to a process machine. A second material outlet is located beneath the first end of the feed screw, with a slide gate blocking the second material outlet. A pneumatic piston is provided for pulling the slide gate to unblock the second material outlet, and a Venturi pump is located under the second material outlet for pulling pellets through the second material outlet when the slide gate is opened.

A fluid delivery system includes a status indicator and control system comprising a processor. The processor is configured to receive a first signal indicative of a first status of operations of a spray application system. The processor is further configured to provide to an operator of a spray gun, via a display system, a visualization representative of the first status of operations, and techniques to control the fluid delivery system, wherein the spray application system is configured to deliver at least one fluid to the spray gun during operations.

A device for producing dyed plastic granulate and undyed plastic granulate includes a multi-shaft screw extruder and an underwater pelletizing installation. A granulate changeover unit which separates the dyed plastic granulate from the undyed plastic granulate is disposed in a conveying direction downstream of the underwater pelletizing installation. The dyed plastic granulate is separated from the pelletizing water via a first separator installation, and the undyed plastic granulate is separated from the pelletizing water via a second separator installation. The separator installations are disposed so as to be mutually parallel. The device enables a simple, flexible and economical selective production of the dyed plastic granulate and the undyed plastic granulate.

An extrusion apparatus intended for the manufacture of a coextruded profiled element P for tyres, produced from rubber compounds of various compositions, comprises a profiling device (30) arranged at the outlet of at least two flow channels (34, 35) for rubbery compounds of different composition. The said channels receive the compounds from positive-displacement contrarotating twin-screw extruders (10, 20), the screw flights interpenetrating and having conjugated profiles.

The present invention relates to a method for the step-by-step guidance of a machine operator of an extrusion device for a film machine when changing from an application formula to a subsequent formula, comprising the following steps: identifying a formula change request, displaying the formula change request for the machine operator, displaying at least one concluding step to be performed for the application formula, identifying a confirmation of the machine operator for the at least one concluding step, displaying at least one preparatory step to be performed for the subsequent formula, identifying a confirmation of the machine operator for the at least one preparatory step, and concluding the change from the application formula to the subsequent formula.

In a method for reprocessing film waste material, the film waste material is comminuted into recycling material by means of a comminuting device. The recycling material is fed by means of a feeding device in a multi-shaft screw machine. In the multi-shaft screw machine, the recycling material is plasticized into a material melt and processed into raw material. The raw material may again be fed to a production installation for the production of films.

In a method for reprocessing film waste material, the film waste material is comminuted into recycling material by means of a comminuting device. The recycling material is fed by means of a feeding device in a multi-shaft screw machine. In the multi-shaft screw machine, the recycling material is plasticized into a material melt and processed into raw material. The raw material may again be fed to a production installation for the production of films.

A device and a method for producing reaction plastics, including a first metering device with a first metering unit and a second metering unit, each of which is suitable for receiving and dispensing a first mixing component in a metered manner, a second metering device which is suitable for receiving and dispensing a second mixing component in a metered manner, and a mixing device which is suitable for receiving and mixing the first mixing component dispensed by the first metering unit and/or the second metering unit of the first metering device and the second mixing component dispensed by the second metering device. For this purpose the first metering unit and the second metering unit are connected to the mixing device such that prior to beginning the mixing process, the first mixing component can be brought to an operating state required for the mixing process, in particular an operating pressure, by guiding the first mixing component from the first metering unit to the second metering unit via the mixing device.

The above object is solved by means of a method comprising the features as described herein as well as an extrusion device comprising the features as described herein. Further features and details of the invention follow from the depending claims, the description and the drawings. It goes without saying that features and details, which are described in connection with the method according to the invention, shall thereby also apply in connection with the extrusion device according to the invention and in each case vice versa, so that, with regard to the disclosure, reference is or can always be mutually made, respectively, to the individual invention aspects.

A mixing method provided by the invention comprises steps of melting a solid-state polymer raw material into a flowable molten raw material fluid to flow into a mixing space at a first volume flow rate, when the raw material fluid entering the mixing space, introducing a foaming agent in a fluid form into the mixing space simultaneously or at a different time, mixing the foaming agent with the molten raw material fluid into a mixture in the mixing space, circulating the mixture in the mixing space at a second volume flow rate, and causing the second volume flow rate greater than the first volume flow rate.