In the case of a die head and a process to produce multilayer tubular film made from thermoplastic polymers, the advantages of radial distributors and axial distributors should be combined. This is achieved in that at least one distributor is a plate distributor and at least one distributor is an axial distributor, whereby the plate distributor is located in an annular element of the axial distributor upstream of the melt merge zone to the ring-shaped die.

Methods, apparatuses, systems, and techniques relate to an extruder unit for producing preforms with a tube-like wall from a polymer melt and an associated extrusion process. The extruder unit has a receptacle for an exchangeable dispensing tool, it furthermore comprises at least two different and alternately usable profiling devices. These profiling devices have outlet-side fastening structures, which correspond in the various profiling devices and form the receptacle for the exchangeable dispensing tool, so that the profiling devices can be connected alternately to the same dispensing tool. In this way, any dispensing tool, depending on the wish of the customer, can be operated with different profiling devices, in particular, on the one hand, to carry out profiling by mandrel body movement or profiling by nozzle body movement.

Methods, apparatuses, systems, and techniques relate to a tube-forming device for an extruder unit or an extrusion device and a tube-forming process. The tube-forming device comprises at least one shaping sleeve, which is designed to shape a supplied stream of polymer melt from a substantially strand-like cross section into a tubular cross section. The shaping sleeve has a guiding passage embedded in the sleeve wall, such that the guiding passage is a cavity which lies within the sleeve wall and, in the radial direction of the shaping sleeve, is enclosed in a sealed manner with respect to the outer surfaces.

Article comprising first and second continuous polymeric layers having at least one polymeric layer exhibiting a random network of strands and connective regions disposed between the first and second continuous polymeric layers. In some embodiments, the article is a tape and polymeric multilayer film having a slip resistant surface.

A system and method are presented in which a flow of plastic is extruded to obtain nano-sized features by forming multiple laminated flow streams, flowing in parallel through the non-rotating extrusion system. Each of the parallel laminated flow streams are subjected to repeated steps in which the flows are compressed, divided, and overlapped to amplify the number of laminations. The parallel amplified laminated flows are rejoined to form a combined laminated output with nano-sized features. The die exit is formed to provide a tubular shape.

The invention relates to a multi-layer blowing head for a blown film installation, to a blown film installation, and to a method for operating a blown film installation. Specifically, according to the invention, a component is included on the opposite side of a distributor plate of a distributor plate set for a spiral distributor, wherein part of the spiral distributor is formed out of the opposite side of a distributor plate. The blowing head according to the invention for forming a multi-layer melt flow makes it possible, in the case of suitable operating parameters, to prevent the occurrence of spiral strips or at least to make said spiral strips less pronounced.

The present invention relates to a method of transforming multilayered and/or multi-component streams into tubular shapes prior to or during extrusion by passing the streams over a deflector. The invention also relates to dies containing spiral, bowtie, circumferential and/or wrapping deflectors and products made by such methods.

A cable has at least one elongated electric conductor and a multilayer insulation surrounding the electric conductor. The multilayer insulation has a first semiconducting layer and an electrically insulating layer. The two layers are made from a silicone rubber based composition. A method for making this cable includes co-extruding the first semiconducting layer and the electrically insulating layer.

A large concentric co-extrusion die (1) is described having a plurality of annular or conical die mandrel layers (201-205). Each layer is formed between a pair of adjacent annular or conical die mandrels (101-106) defining between them a flow path for molten thermoplastics material from an inlet to an annular extrusion outlet (110) through which a thermoplastics tubular extrusion is formed in use. Extrusion takes place through the multiple annular layer outlets (301-305) to form a multi-layered product. At least one layer (203) of the annular or conical die mandrels has a plurality of molten material inlets arranged around the external circumference of the co-extrusion die with each inlet being connected to a feed channel (403) which has plural bifurcations (403.1, 403.2, 403.3) providing 2.sup.n subsidiary outlet feed channels (503) where n is the number of bifurcations. Each subsidiary outlet feed channel being connected to a corresponding helical outlet channel (703).

A coextrusion die for manufacturing multilayer, coextruded, tubular preforms made from thermoplastic plastic. A storage cylinder element has an inner storage space. A spindle, and an annular storage space is formed between the spindle and the storage cylinder element, which opens into an output ring channel. An extrusion head, which is axially displaceable with respect to the storage cylinder element includes a ring piston, in which at least two heart distributor elements are coaxially arranged. A flow channel is formed in each case between the ring piston and the adjacent heart distributor element as well as between each of two heart distributor elements, which widens from an inlet opening to a distributor ring channel from where it transitions into a cylindrical ring channel as a frustoconical ring channel.