Vorrichtung zur Fertigung rohrfoermiger Erzeugnisse

1,191,711. Extruding reinforced tubes. N. N. VINOGRADOV, G. K. STUKALEV, and P. V. KUZMINOV. 20 June, 1967, No. 28471/67. Heading B5A. Plastics tubing with a reinforcing helical wire core is moulded when an annular member 7 mounted around a core 6 rotates and feeds a wire in the form of a helical coil from a helical passage 9, Figs. 3, 4 (not shown.) formed on the interior surface of the mandrel, the coil being larger in diameter than the core 6 and being completely embedded in plastics material simultaneously fed from an extrusion press (not shown). The wire is fed to the passage 9 by rollers 15, 16 from a spool or spools 14, the rotation of rollers 15, 16 being controlled through gears 23-28 from the rotation of a sprocket 11 which also causes rotation of the mandrel 7. The interior surface on which the helical passage (9) is formed is conical and flared outwardly in the direction of travel of the plastics material.