Measurement and Control of Temperature

The increasing demands of obtaining greater throughput with increased quality from extrusion products have made accurate measurement and control of temperature more important than ever. This chapter describes in general terms techniques of measuring temperature, heating and cooling systems, and concepts of closed loop control and then contrasts conventional and microprocessor implementations. Since the more exacting requirements demand that process control schemes be applied to extrusion it is not possible to consider the temperature problem in isolation. Therefore a total control system for an extrusion factory is discussed and finally an attempt is made to look into the future.