摘要 |
A process for reducing the shrinkage of profiled elements of thermoplastic synthetic resins, which normally occurs due to undesired stresses frozen in during extrusion in an extruder die and calibration in a calibrating device, involves the step of maintaining the extrusion speed of the profiled element upon exiting from the extruder die at least the same or almost the same as the calibrating speed and/or take-off speed of the profiled element during its subsequent passage through the calibrating device. Also, it is advantageous to cool selected and defined portions of the periphery of the extrudate during the initial stage of calibration within the calibrating device so that a reinforced frame or corset is formed within the extrudate. |