Abstract: Described is an apparatus for the production of transversely ribbed tubes, having mold jaw halves which are circulatingly movable in a condition of bearing against each other along two endless guide paths by means of a respective associated drive device. The two guide paths have a common mold section, a respective return section and two respective direction-changing sections. The respective direction-changing section has a direction-changing member having a clothoid-like guide edge in order at the transition between the respective return section and the adjoining direction-changing section and at the transition between the respective direction-changing section and the adjoining mold section and vice-versa to prevent an unwanted jump on the part of the mold jaw halves and in that way to be able to increase the advance speed of the mold jaw halves and improve the productivity of the apparatus.

Abstract: Described is an installation (10) for producing multi-layer composite tubes (116). The installation (10) has a metal strip unwinding device (44), a metal strip storage device (48) adjoining the metal strip unwinding device (44), a metal strip shaping device (36) adjoining the metal strip storage device (48), an extruder station (12) adjoining the metal strip shaping device (36), and a cooling device (50) adjoining the extruder station (12). The metal strip shaping device (36) serves for shaping the metal strip (38) which is unwound from the metal strip unwinding device (44) into a metal tube with overlapping longitudinal edges which are welded to form the metal tube by means of a welding station (32) at the extruder station (12). In the extruder station (12) the metal tube is covered with an inner plastic layer in fixedly adhering relationship and with an outer plastic layer in fixedly adhering relationship. The composite tube produced in that way is cooled to ambient temperature in the cooling device (50).

Abstract: There is described an apparatus (10) which is provided for the production of tubes with a transversely profiled wall. The apparatus (10) has shaping halves (16, 30) which move along two paths (14) closed in themselves and form a common shaping section (18) and two return sections (20). Provided at each of the two return sections (20) is a respective turning device (26) at which two shaping halves (16, 30) are disposed by means of a holding and release device (32). The one shaping half (30) has a socket contour in order to be able to produce transversely profiled tubes with sockets, with the apparatus (10).

Abstract: Proposed is a device for continuously producing seamless plastic tubes, wherein provided as a distributor element for the molten material to be fed to an annular gap is a distributor plate which is arranged within the cross-section of the mold cavity and in which the molten plastic material is passed to the peripheral surface of the distributor plate substantially radially with respect to the direction of production by way of distribution passages which branch tree-like, wherein the flow path of the molten plastic material is the same in each of the individual distribution passages between the entry opening and the peripheral surface

Abstract: Described is an apparatus for the production of transversely ribbed tubes, having mold jaw halves which bear against each other along a common mold section and form a mold passage. Each mold jaw half has a cooling passage which is produced directly during the operation of casting the respective mold jaw half, for example by means of a so-called false casting core. The cooling passage extends in the corresponding mold jaw half from a first surface to a second surface so that said core can be easily removed from the casting of the mold jaw half. At the one surface, the cooling passage has a cooling agent feed means and, at a spacing therefrom, a cooling agent discharge means. The second surface which is at a distance therefrom is sealed off by means of a guide and slide element which is fixed to the corresponding mold jaw half.

Abstract: Described is an apparatus for the production of transversely ribbed tubes, having mold jaw halves which bear against each other along a common mold section with front faces and form therebetween a mold passage. Each mold jaw half has vacuum passages which are in flow communication with the mold passage. Each mold jaw half also has a cooling passage (22). The front faces of the mold jaw halves are formed with vacuum communication channels which, along the common mold section, form vacuum communication passages. The vacuum communication passages are in flow communication with a stationary vacuum rail, along the common mold section of the apparatus. Along the common mold section, the cooling passages of the mold jaw halves are in fluid communication with a stationary cooling agent rail which has a cooling agent feed means and a cooling agent discharge means.

Abstract: Described is an apparatus for the production of transversely ribbed tubes, having mold jaw halves which bear against each other along a common mold section with front faces, and form a mold passage. Each mold jaw half is connected at a surface to a support element. The support elements are guided along a first linear guide device. A guide and slide element is fixed to a second surface of each mold jaw half. The guide and slide elements are guided along a second linear guide device. The support elements and the guide and slide elements comprise the same material. The mold jaw halves comprise a material of relatively low specific weight and a coefficient of thermal expansion (.alpha..sub.B) which is high in comparison with the coefficient of thermal expansion (.alpha..sub.A) of the material for the support elements and the guide and slide elements.

Abstract: In an apparatus for the production of corrugated plastic tubes an extrusion device passes plastic material into a perpendicularly arranged injection head for injecting the plastic material into a perpendicularly arranged mold section comprising at least two pairs of movable mold jaws arranged in axially mutually superposed relationship. A drive device is associated with each pair of mold jaws for displacement thereof in the radial and axial directions.

Abstract: In the production of plastic tubes or pipes which are internally smooth-walled but have peripheral ribs externally, in particular from extrudable, more especially thermoplastic plastic such as PVC, a good filling of the cavities in the moving mold which are provided to form the ribs, is achieved in that said cavities are filled with the molten plastic first at a distance from the separating plane of the moving mold and last in the region of said separating plane.

Abstract: The invention relates to an apparatus for the continuous production of pipes with cross-profiled walls from a pipe strand of thermoplastic plastic emerging in still plastic state from an extrusion nozzle.