ENERGY CONSUMPTION IN INJECTION MOULDING: A CASE STUDY.

Energy consumption is a key parameter to determine manufacturing process efficiency and sustainability, therefore, analysing plastic injection moulding from an energy perspective is fundamental. In this context, this study presents the analysis on an industrial case to produce shoe soles. The daily injection process was monitored with one power quality analyser and the process was observed at the industrial site. Power data were examined in contrast with the PVC products generated by the rotary table injection machine. It was determined that the production method used was a key factor affecting energy consumption, resulting in a non-productive energy as high as 60%. Furthermore, an important amount of energy was not being used in value added activities. The net energy required to produce a product was found to be approximately 72 Wh for a juvenile sole and 160 Wh for an adult sole. Nevertheless, the energy per product increased to 128 Wh for a juvenile sole when the energy of a cycle (a table revolution) was distributed over the generated products. This analysis has provided the company a first approximation to the amount of non-productive energy in a manufacturing cycle. [ABSTRACT FROM AUTHOR]