Abstract: A process for the production of dish-shaped moldings or hollow bodies of thermoplastic material comprises the step of producing an at least approximately tubular preform by the extrusion of thermoplastic material. The preform is axially divided to form at least one single-layer web of material which is removed from the extrusion head by being engaged by means of a manipulator which spreads and/or straightens the web transversely with respect to the extrusion direction. The web is then transferred to a molding tool by a manipulator for it to be put into its final form in its first heat in the molding tool.

Abstract: A process for the production of dish-shaped moldings or hollow bodies of thermoplastic material comprises the step of producing an at least approximately tubular preform by the extrusion of thermoplastic material. The preform is axially divided to form at least one single-layer web of material which is removed from the extrusion head by being engaged by means of a manipulator which spreads and/or straightens the web transversely with respect to the extrusion direction. The web is then transferred to a molding tool by a manipulator for it to be put into its final form in its first heat in the molding tool.

Abstract: In a process for the production of a hollow body of thermoplastic material which is to include an additional portion, by expansion of a preform in a blow molding mold, the additional portion is connected to the hollow body upon expansion of the preform to form the hollow body. To form the connection between the hollow body and the additional portion, the latter is heated by a heating element which is brought into contact with at least the surface of the additional portion that is to involve the welded connection to the hollow body, prior to expansion of the preform. The heating element is brought into contact with the additional portion when already disposed in the blow molding mold in order in that way to heat at least the appropriate surface of the additional portion to a temperature which premotes the production of an adhesive join to the hollow body. The region of the additional portion that is to be heated is at least substantially covered relative to the outside atmosphere by the heating element.

Abstract: In a process for producing a hollow body with a wall which partially comprises foamed thermoplastic material by an extrusion blow molding procedure, a preform which comprises at least first and second layers of which at least one comprises foamable plastics material is first extruded, the layer of foamable material is foamed, and then the preform is expanded in a blow molding mold by the application of an internal pressure. The hollow body may have a welded seam at a region of the hollow body at which an operation of squeezing off excess material has been carried out, the seam being in the form of an outwardly projecting flange web portion and the thickness thereof being such that the layer of foamable material is compressed at least to such an extent that it is not thicker than in the unfoamed condition.