IN-LINE PROCESS MONITORING FOR INJECTION-MOLDING CONTROL

Injection moulding is one of the most important and efficient manufact uring techniques for polymeric materials, with the capability to manuf acture high value added products. Integration of injection moulding ma chines into a computer integrated manufacturing (CIM) system requires reliable process monitoring allowing statistical process control (SPC) to be implemented. CIM systems are concerned with computer control an d linking together of all functions in the manufacturing environment. Successful implementation of CIM requires accurate, reliable and meani ngful information relating to all aspects of the manufacturing process . Hydraulic injection pressure measurements are shown to be important process parameters, indicating, with comparable precision to nozzle me lt pressure, relative changes in polymer melt viscosity.