Injection moulding is one of the most important manufacturing processes in the plastic industry. The temperature distribution of the polymer, while it is inside the mould cavity, influences the properties of the product. The measurement and control of these temperature profiles can enhance the economy of the process and the part quality. / A method to measure melt temperature inside the mould cavity was developed. It consists of an insert, located in the movable plate, that can place thermocouples at different positions. The depth of the thermocouple tip is adjusted manually. These sensors offer an attractive way to perform the measurements because of their easy calibration procedure. The temperature measurements were influenced by the thermocouple tip geometry. / Data were collected at different locations and depths of the mould cavity and the temperature profiles were analyzed. The temperature distribution depended on the wall temperature and the temperature of the polymer as it enters the cavity. The effect of different flow rates was also studied and it demonstrated to affect the temperature profiles. / A control algorithm was developed to control the average of the peak temperatures at three locations in the cavity. The manipulated variable was the coolant temperature and the process disturbance was the front barrel temperature. The transfer functions of the controlled variable with respect to the manipulated and disturbance variables were identified and modeled. / Finally two controllers were designed, tuned, simulated and implemented on the machine. The first is a static feedforward - feedback controller, and the second is a dynamic feedforward - feedback controller. The feedback loop was designed using an internal model control (IMC) algorithm. The static feedforward - feedback controller was found to have a better performance.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.27241 |
| Date | January 1996 |
| Creators | Manero, Federico. |
| Contributors | Kamal, M. R. (advisor), Patterson, W. I. (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Engineering (Department of Chemical Engineering.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001572522, proquestno: MQ29614, Theses scanned by UMI/ProQuest. |
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