| 摘要 |
The extrusion of hollow-section high-shrink polymer e.g. polyethylene, with internal stiffeners dividing its interior into longitudinal spaces, extrudes from a head through a torpedo nozzle into a finishing and cooling zone; the axis of extrusion has a slight gradient; coolant is introduced by a pointed jet into the internal spaces at the finishing and cooling zone some distance from the torpedo nozzle. The process has a much higher prodn. rate than one with conventional cooling, is suitable for low conductivity high-shrink polymer and produces accurate sections. |
