The invention relates to a method for determining at least one layer property of a layer to be determined, in particular a foam layer (16), in an extrusion process, where a supply material (7) is at least partially foamed and an extrusion product (2) with the foam layer (16) is put out, comprising at least the following steps: a) irradiating said extrusion product (2) using electro-magnetic radiation (S), b) electro-magnetically measuring at least one radiation (R) having travelled through said foam layer (16), c) measuring at least one feed-in rate or feed-in volume of the supply material (7), and d) determining the at least one material property of said layer (16) to be determined from the measured feed-in volume (z) and the electro-magnetic measurement.

An extrusion device that produces plastic film includes at least two feed units that feed feedstock to an extruder, wherein each feed unit has at least one discharge opening including a discharge closure to open and close the discharge opening, and a container interface that reversibly fastens a discharge container that accommodates feedstock discharged from the respective feed unit.

A silicon extrusion plant has a silicon extruder and a silicon feed device configured to load the silicon extruder. The silicon feed device has a feed hopper. The feed hopper opens into a feed opening arranged at the bottom thereof. The feed opening is in a fluidic connection, via a feed duct, with an inlet zone of the silicon extruder. A feed screw arranged in the feed hopper in such a way as to be drivable for rotation protrudes into the feed opening at least partly. The feed screw has a cone portion and a cylinder portion. According to another aspect, the silicon extrusion plant has at least one feed pressure sensor configured to measure an actual feed pressure of silicon material to be extruded. The pressure sensor is arranged in a transition region between the silicon feed device and the silicon extruder. A control unit is in a signal communication with the feed pressure sensor and a feed drive device in order to drive the silicon feed device. The control unit is used to define a nominal feed pressure and to transmit an actuating signal to the feed drive device depending on a difference detected between the nominal feed pressure and the actual feed pressure. As a result, a silicon extruder is obtained that is usable for the mass production of silicon extrudate.

An extrusion device that produces plastic film includes at least two feed units that feed feedstock for an extruder, wherein, in each feed unit an automatic cleaning device is arranged for a removal of feedstock from the feed unit when changing material in the extrusion device.

The present invention relates to a method for changing material in an extrusion device comprising at least two supply devices for supplying feedstock for an extruder, comprising the following steps: identifying a change request for changing material in an extrusion device, predetermining a production stability for a time after the material of at least one supply device has been changed, comparing the predetermined production stability to a threshold value of stability, changing the material in at least one supply device depending on the result of comparison.

The present invention relates to a method for changing material in an extrusion device comprising at least two supply devices for supplying feedstock for an extruder, comprising the following steps: identifying a change request for changing the material in the extrusion device, preparing the supply devices for changing the material, separating at least two supply devices from the feed of feedstock to the extruder, discharging feedstock from the separated supply devices, filling subsequent material into the empty supply devices.

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.

A controlled, variable speed vacuum pump with a flow limiter connected to the suction head of the vacuum pump conveys granular plastic resin material from a supply to receivers retaining and dispensing resin when needed by a process machine.

The present invention relates to a method for preparing for a change of material in an extrusion device for a film machine comprising at least one feed unit for feeding feedstock to an extruder, comprising the following steps: predetermining an end of a production order of an extrusion device, specifying a reduced changing filling level for the at least one feed unit, and maintaining the filling level of the at least one feed unit at the reduced changing filling level for the further production with the extrusion device.

A piece insertion method for a pipe, for example an irrigation pipe, including: ejecting at least one piece, for example a dripper, from an ejection unit, advancing the at least one dripper inside the irrigation pipe by a dripper advancing unit, lifting the dripper towards the inner surface of the irrigation pipe by using a lifting device such that the dripper is parallel or substantially parallel to this inner surface of the irrigation pipe on impact with this inner surface. The method according to the invention allows also coordination between the lifting device, the ejection unit and the dripper advancing unit such that the dripper spacing can be maintained in tight tolerances.