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 process for the calibration of a profiled article of thermoplastic synthetic resin wherein a vacuum is applied to the external surface of the profiled article while the article is drawn through a calibrating tool and wherein the profile surface of the profiled article is cooled indirectly by a liquid coolant flowing through ducts within the calibrating tool involves applying a vacuum via a plurality of slots within the calibrating tool which are placed adjoining the profile surface and feeding coolant through the ducts of the calibrating tool in such a manner that the coolant is discharged by means of the vacuum via the profile surface which is under the vacuum.

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 the calibration of a profiled article of thermoplastic synthetic resin wherein a vacuum is applied to the external surface of the profiled article while the article is drawn through a calibrating tool and wherein the profile surface of the profiled article is cooled indirectly by a liquid coolant flowing through ducts within the calibrating tool involves applying a vacuum via a plurality of slots within the calibrating tool which are place adjoining the profile surface and feeding coolant through the ducts of the calibrating tool in such a manner that the coolant is discharged by means of the vacuum via the profile surface which is under the vacuum.