Modelling the energy consumption in the injection moulding process

Plastic is one of the most widely used materials and injection moulding is the most common manufacturing process to produce plastic parts. Although injection moulding may appear harmless regarding energy consumption, the large scale of this process makes its impacts especially significant and even minor efficiency improvements may lead to high overall energy savings. Moreover, energy consumption affects not only the manufacturing costs but also the manufacturing environmental impact and so it is a critical component in any overall sustainability strategy. This paper presents a model to estimate in an early design phase the energy consumption in the production of injection moulding parts. The proposed model is sensitive to different part designs, different machines and process conditions. An energy balance is proposed, comprising two components, a thermodynamic model and an empirical machine model, integrating coefficients sensitive to both part design and machine characteristics.