Abstract: An apparatus for extruding a thermoplastic laminate has a nozzle assembly having a nozzle body centered generally on a plane and formed at the plane with a merge passage, with an outlet slot opening in one direction from the merge passage, with core-layer distribution and intake passages centered on the plane and opening in the opposite direction into the merge passage, and with cover-layer distribution and intake passages opening laterally into the merge passage. A core-layer fitting formed with tempering chambers forms part of the core-layer intake passage and a trimmings fitting mounted on the nozzle body has a trimmings intake passage and a trimmings feed passage extending therefrom to the cover-layer distribution passage. A liquefied core-layer resin is fed under pressure to the core-layer intake passage and therethrough to the merge passage and outlet slot.

Abstract: An extruder die for extrusion of a multilayer thermoplastic laminate, particularly in the form of a foil or plate, comprises a multicomponent block symmetric with respect to a central plane dividing a plurality of feed channels and distributing channels connected to said feed channels, at least one mouth and a central distributor channel connected to and following said mouth symmetric in relation to the axis of said extruder die as well as an outlet die following said central distributor channel. The block has on the end opposite the outlet die an additional feed channel with a round or rectangular cross section for feeding in a special plastic material which changes over into a discharge duct extending to the mouth.

Abstract: The apparatus for continuous extrusion of a plastic laminate has at least two extrusion screw presses, an accumulator block, a transition unit, and an output die, from which the plastic laminate product is extruded. The accumulator block has a combining channel or canal therein which is fed by the extrusion screw presses. This combining canal is connected by way of the transition unit to the output die. The combining canal preferably has a rectangular cross section with rounded corners and at its upstream end is directly connected to a first extrusion screw press by way of a connecting canal coaxial with the combining canal. Downstreamwards below the connecting canal is found at least one input metering slot connected to the combining canal at one end and through a connecting apparatus at its other end to an additional extrusion screw press, this input metering slot lying between an input plate and an adjusting bar guided in an adjusting bar recess.

Abstract: A die for a thermoplastic material with at least one output-gap-defining adjustable die lip, an opposing gap-bounding lip, at least one adjusting element working on the output-gap-defining die lip as well as a control and adjusting device for the thickness of the extruded plastic product, wherein the adjusting element is associated with and operated at least partially by the control and adjusting device. A field translator, either a piezotranslator or a magnetostriction translator, is employed as the adjusting element.

Abstract: An extruder press unit for extrusion of a thermoplastic material has at least one output gap in an extruder body, wherein the output gap is formed by an output gap-defining adjustable extruder lip and an opposing gap-bounding lip. This output gap is adjustable with the help of a mechanical coarse adjusting mechanism to a given gap width, and the gap-defining adjustable extruder lip is connected to at least one adjusting element, to which a control and adjusting device for the thickness of the extruded material is associated. The opposing gap-bounding lip is likewise constructed as an adjustable structural component. The coarse adjusting mechanism operates on the opposing gap bounding lip. A field translator is employed as at least one of the adjusting elements and of course in the form of either a piezotransistor or a magnetrostriction translator. The control and adjusting device is set up for a fine adjustment in the range between 0.05 and 0.3 mm, preferably between 0.10 to 0.20 mm.

Abstract: An apparatus for the cooling, straightening and calibration of a plate-shaped synthetic-resin strand, e.g. of thermoplastic material extruded from a broad-slot nozzle comprises a plurality of straightening rollers on respective stands, the rollers of each stand engaging opposite surfaces of the strand. The rollers are provided with cooling and heating means to ensure homogeneous temperature distribution throughout the strand passing between the pairs of rollers which can be aligned with one another or can be offset from one another. On at least one of the stands the rollers are displaceable alternately parallel to the path of the strand by corresponding oscillating drive.

Abstract: An apparatus for the extrusion of tubular bodies of synthetic-resin material and especially large-diameter pipes, in which the die for forming the tube is connected to an extrusion press and includes an outer member and an inner member between which the material is forced. On the outer member there is provided a calibrating sleeve and the die carries a radioactive thickness-measuring means.

Abstract: The synthetic-resin tube emerging from an extrusion die is internally sealed by a pair of sealing members having inflatable peripheries and connected to flexible members running back through the die so that one of the seals can be drawn toward the die while the other is entrained with the tube away from the latter and vice versa.