A method for forming a multilayer plastic sheet material is disclosed, where a first polymer mass is melted under pressure and is passed through an extruder head at a specified discharge rate in the form of a plastic strand in sheet form that is provided with one or more layers so that a multilayer plastic strand is formed. This is passed to two or more rolls of a finishing stand that processes the multilayer plastic strand into a sheet. After the plastic strand in sheet form leaves the extruder head, it is first passed between a top roll and a bottom roll of a roughing stand. The speed of the rolls of the finishing stand and the rolls of the roughing stand is synchronized with the discharge rate of the plastic strand in sheet form from the extruder head, so that the plastic strand is processed without stress.

The invention relates to a device and a method for controlling the feed of polymer melt, which has been discharged from an extruder, to a plastics processing machine formed from at least two subunits (1, 2), to which the polymer melt discharged from the extruder is fed via a distributor (13) which is positioned downstream of the extruder and which serves for splitting up the polymer melt into partial streams corresponding to the number of subunits. According to the invention, the partial streams are each fed to a subunit by means of a gearwheel pump (11, 12). The volume flows fed to the subunits (1, 2), which are of substantially identical design, can be respectively separately controlled in open-loop or closed-loop fashion through control of the drive rotational speed of the respective gearwheel pump (11, 12) in a manner dependent on operating parameters and/or the configuration of the respective subunit (1, 2).

A system for adjusting a gap in a slot die for producing a polymeric web. The system includes a slot die that has a polymer reservoir that extends between a polymer inlet and a melt outlet. The melt outlet has a first edge and a second edge that each extend longitudinally along the melt outlet. The second edge is opposite the first edge. A plurality of actuators move the second edge along a plurality of positions along a length of the second edge. The first edge is spaced apart from the second edge by a gap that has an adjustable profile. A pressure sensor communicates with the reservoir and measures the pressure of the polymer in the reservoir. A control unit with an algorithm correlates the profile of the gap to the pressure in the reservoir. The algorithm is configured to generate control signals to cause the profile of the gap to be uniform.

A method of forming an oral product includes extruding a mixture, conveying the extruded mixture through one or more pairs of forming rollers, and cutting the extruded mixture into one or more oral products. The mixture can include polymer and at least one flavorant, sweetener, active ingredient, or combination thereof. The extruded mixture forms an extrudate having a predetermined cross-sectional shape. The one or more pairs of forming rollers abut to define a passage there between as each forming roller rotates. The passage has a cross-sectional shape corresponding to the predetermined cross-sectional shape. The method can be performed using a machine including an extruder, one or more pairs of forming rollers, and a cutting device.

A method for producing a fused unplasticised polyvinyl chloride (UPVC) article (126) is provided. The method includes feeding an UPVC blend (103) into a co-rotating twin-screw extruder (100). The method further includes melting the UPVC blend (103) and conveying fused UPVC to an outlet (120) of the co-rotating twin-screw extruder (100). The method also includes collecting the fused UPVC from the outlet (120) at a rate of at least 100 kilograms/hour per litre of free volume (124) of the co-rotating twin-screw extruder (100).

An apparatus includes an extruding device configured to dispense a dielectric material though an orifice, a wire feed device configured to feed a conductive wire through the orifice, and a cutting device configured to sever the wire. It also includes an electronic controller configured to control the extruding device, the wire feed device, and the cutting device. The electronic controller commands the extruding device to dispense the dielectric material though the orifice, the wire feed device to feed the wire through the orifice, and the cutting device to sever the wire, thereby forming a dielectric substrate encasing a plurality of wires. The electronic controller further commands the extruding device to form an opening defined in the substrate in which plurality of electrically conductive wires is exposed and a location feature on the substrate located with a positional tolerance less than or equal to 1 mm relative to the opening.

The method for setting an operating point of a film stretching system comprises the method steps: acquiring an input, wherein the input contains: a) a target value for the first production variable; or b) a target value for the second production variable; or c) a target value for the third production variable; specifying: a) a setting value for the second production variable and the third production variable in order to achieve the target value for the first production variable; or b) a setting value for the first production variable and the third production variable in order to achieve the target value for the second production variable); or c) a setting value for the first production variable and the second production variable in order to achieve the target value for the third production variable; controlling the motor arrangement and the extruder arrangement by the control device in such a way that the operating point consisting of the target value and two setting values is reached.

An air ring comprises a circular plenum in fluid communication with a source of pressurized air. An upper and lower annular lips are in fluid communication with the plenum through upper and lower channels and are arranged to supply air to the blown film bubble. A plurality of vanes are disposed in the upper channel and extend radially inwardly from the plenum to the upper annular lip. The vanes divide the upper channel into a plurality of radially extending channel segments. Each vane has a selected length and a distal end proximal the upper annular lip, the distal end being spaced from the upper annular lip no greater than about 20% of the length of the vanes. A powered plunger extends between the vanes of each of the channel segments to vary the cross-sectional area of the channel segments.

Disclosed is an apparatus for the production of a blown tubular film (FT). The apparatus includes an independent device for the localized thickness adjustment at the strips adjacent to the folding edges resulting from the flattening of the tubular film (FT) by means of adjustment elements formed in angular sectors of limited extension symmetrically arranged 180° apart. The independent device for the localized thickness adjustment being a volumetric type device having a rotating ring that performs a rotating adjustment of the flow rate of a cooling air stream which takes into account the angular offset resulting from the operational parameters of the apparatus.

An extruding system includes a melting unit configured to convey a polymeric material, a mixing unit configured to mix the polymeric material with a blowing agent to form a mixture, an injection unit configured to inject the mixture, a first flow control element disposed between the melting unit and the mixing unit, and a second flow control element disposed between the mixing unit and the injection unit. A method of extruding includes conveying a polymeric material from a melting unit to a mixing unit, conveying a blowing agent into the mixing unit, mixing the polymeric material with the blowing agent to form a mixture, conveying the mixture from the mixing unit to an injection unit, and discharging the mixture from the injection unit, wherein flow of the polymeric material is controlled by a first flow control element, and flow of the mixture is controlled by a second flow control element.