procedure for quality control of schmelzeextrudierten plastics through monitoring the dynamic viscosity of the melt in extrusion

摘要

A process and a device for product monitoring of melt-extruded plastics, in particular chemical fibres, is proposed, in which the dynamic viscosity of the melt at the end of the melting extruder is monitored. In a measurement zone of the melt stream leading to a consumer, the pressure loss and the temperature are measured for this purpose and input into a computer. Since with constant delivery of the melt from the measurement zone by means of a volumetrically operating metering pump, the pressure loss is directly proportional to the viscosity, a good opportunity is provided for monitoring the effects of the extruder operation on the product quality and, by corresponding interventions, of controlling the melting process with the object of providing the desired quality.