Abstract: A process for the manufacture of a launching tube with an internal guide surface for effecting controlled spin missiles, such as rockets, wherein the launching tube is provided on the inside with helically extending grooves and/or ridges contacting guide cams or the like of the missiles for guiding therealong; this launching tube is extruded, and sized, from a molding composition containing fiber-reinforced thermoplastic synthetic resin, to have integrally formed, slightly helically extending grooves and/or ridges.

Abstract: A launching tube with an internal guide surface for effecting controlled spin for missiles, such as rockets, wherein the launching tube is provided on the inside with helically extending grooves and/or ridges contacting guide cams or the like of the missiles for guiding therealong. This launching tube is extruded, and sized, from a molding composition containing fiber-reinforced thermoplastic synthetic resin, to have integrally formed, slightly helically extending grooves and/or ridges.

Abstract: A profile strip, especially suitable for the production of window or door frames, has an optionally hollow core profile made from a glass fiber-reinforced PVC composition and a shell made from a synthetic resin compatible with PVC and exceeding the impact resistance of the core profile.

Abstract: A die, associated with an extruder and provided with an inwrought flow channel with displacement cores for shaping a plasticized synthetic resin bulk stream into a profile cross-section with hollow chambers, has a die housing that is composed of several die members with vertical and/or horizontal mold joints. The displacement cores in the flow channel are connected to the die housing by core-holding webs that separate the flow channel by distances corresponding to the thicknesses of the webs, thus subdividing the bulk stream into separate partial streams, the cross-section of the combined partial streams being equal to the cross-section of the bulk stream, and the displacement cores being enlarged by the thickness of the core-holding webs so that the partial streams, with the flow cross-sections remaining the same, are conducted along the core-holding webs.

Abstract: A glass fiber-reinforced polyvinyl chloride composition contains, per 100 parts by weight of polyvinyl chloride of a K value of between 55 and 75, 40-100 parts by weight of glass fibers having a diameter of between 5 and 25 .mu.m with a length of 0.5 to 12 mm, and 1-25 parts by weight of mineral filler having an average particle diameter of below 50 .mu.m.

Abstract: A process for producing elongated profile members made of thermoplastic synthetic resins having a coating over at least a portion of their circumference of at least one additional thermoplastic polymeric material which includes the steps of extruding a coating of a thermoplastic secondary material, simultaneously and continuously with the extrusion of the elongated profile member, onto said member while said member is still within the plastic temperature range, and subsequently sizing the resultant coated member.

Abstract: A process for producing elongated profile members made of thermoplastic synthetic resins having a coating over at least a portion of their circumference of at least one additional thermoplastic polymeric material which includes the steps of extruding a coating of a thermoplastic secondary material, simultaneously and continuously with the extrusion of the elongated profile member, onto said member while said member is still within the plastic temperature range, and subsequently sizing the resultant coated member.

Abstract: A process for the extrusion of patterned sheets of thermoplastic synthetic resins wherein a transparent basic synthetic resin material is combined with at least one differently colored secondary synthetic resin material, and wherein the combined stream of material made up of the basic material and the secondary material flows, during the extrusion, at least in partial zones at right angles to the extrusion flow direction, based on the flow cross section, is disclosed.

Abstract: A process for extruding patterned sheets or panels of differently colored thermoplastic synthetic resin compositions which include the steps of distributing additional color compositions outside of an extrusion duct of a basic color composition over a number of individual feed channels and introducing the additional color compositions at right angles to the direction of flow of the basic color composition into the interior of the stream of the basic color composition at locations over the width and thickness in an initial flow zone via said channels.

Abstract: A process for sizing an extruded thermoplastic structure or member formed by coextrusion of a core profile of one thermoplastic material and a cover layer of another thermoplastic material provided over a portion of the periphery of the core profile which includes the steps of sizing the extruded plastic structure in the external cross sectional dimensions, cooling during the sizing step the structure and effecting a different temperature control of the cooling of the cross section of the profile depending upon the thermoplastic material being cooled. The thermoplastic material having the higher Vicat softening temperature being more gradually cooled than the one having a lower Vicat softening temperature.