Polymer injection-molding is one of the most used manufacturing processes for the production of plastic products. Its electricity consumption highly influences its cost as well as its environmental impact. Reducing these factors is one of the challenges that material science and production engineering face today. However, there is currently a lack of data regarding electricity consumption values for injection-molding, which leads to significant errors due to the inherent high variability of injection-molding and its configurations. In this paper, an empirical model is proposed to better estimate the electricity consumption and the environmental impact of the injection-molding process. This empirical model was created after measuring the electricity consumption of a wide range of parts. It provides a method to estimate both electricity consumption and environmental impact, taking into account characteristics of both the molded parts and the molding machine. A case study of an induction cooktop housing is presented, showing adequate accuracy of the empirical model and the importance of proper machine selection to reduce cost, electricity consumption, and environmental impact.

During the last decades, society’s concern for the environment has increased. Specific tools like the Life Cycle Assessment (LCA), and software and databases to apply this method have been developed to calculate the environmental burden of products or processes. Calculating the environmental impact of plastic products is relevant as the global plastics production rose to 288 million tons in 2012. Among the different ways of processing plastics, the injection molding process is one of the most used in the industry worldwide. In this paper, a sensitivity analysis of the environmental impact of the injection molding process has been carried out. In order to perform this study, the EcoInvent database inventory for injection molding, and the data from which this database is created, have been studied. Generally, when an LCA of a product is carried out, databases such as EcoInvent, where materials, processes and transports are characterized providing average values, are used to quantify the environmental impact. This approach can be good enough in some cases but in order to assess a specific production process, like injection molding, a further level of detail is needed. This study shows how the final results of environmental impact differ for injection molding when using the PVC’s, PP’s or PET’s data. This aspect suggests the necessity of studying, in a more precise way, this process, to correctly evaluate its environmental burden. This also allows us to identify priority areas and thereby actions to develop a more sustainable way of manufacturing plastics.

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During the last decades the environmental concern of society has experienced an increase. Specific tools like the Life Cycle Assessment (LCA), and software and databases to apply this method have been developed to calculate the environmental burden of products or processes very diverse. Global plastics production rose to 288 million tonnes in 2012. Among the different ways of plastics processing the injection molding process is one of the most used in the industry worldwide. In this paper an analysis of the influence of the polymer in the environmental impact of the injection molding process has been carried out. In order to perform this study, the EcoInvent database inventory considered and the data from which this database is obtained for this process have been studied. In general, when a LCA of a product is carried out, databases such EcoInvent, where materials, processes and transports are characterized providing average values, are used. This approach can be good enough for some cases but in order to assess a specific process, like the injection molding process, a further level of detail is needed. This study shows how the final results of environmental impact differ significantly when modifying the generic dataset's values, using the PVC's, PP's or PET's original report data or more updated values. This aspect suggest the necessity of studying, in a more precise way, this process to evaluate its environmental burden correctly so the priority areas can be properly identified and thereby actions to develop a more sustainable way of manufacturing can be determined.

Environmental conscience has been growing gradually in recent decades. The market is demanding ecological actions over the products, and legislation is introducing ecodesign measures in products. Because of that, ecodesign is becoming an important discipline in engineering, to take into account the environmental impact of the product during its development, performing Life Cycle Assessment, but it is not still a common discipline in engineering. Training focused on LCA for product development is essential to introduce ecodesign between engineering students, who are not used to work with environmental concepts. The best tool for this training is LCA software to learn through the practice how to calculate the environmental impact of a design, and how this results can be used to improve their designs from an ecological point of view. This work presents the ECOTOOL, software designed to train engineers in LCA methodology. Current existing LCA software are not prepared to be used by untrained engineers, sometimes because they are difficult to be used due to large databases and the complex working environment, and sometimes they are extremely simplified, not sensitive to design modifications. ECOTOOL allows complete LCA performing with a working environment similar to other engineering tools, like professional CAD software, well known by engineers. It is provided with reduced databases, training helps, simplified results and an intuitive working environment to allow students to easily analyze the environmental impact of their designs and apply design actions to optimize it, at the same time they learn the concepts of LCA methodology. Comments to the editor: Thank you for your kind review. The claim that 'the market is demanding ecological actions' will be explained and justified in the paper, as there are links between European legislation and the environmental conscience in Europe. The expression "appropriate training" has been modified in the abstract to avoid misunderstandings. With “appropriate” we intended to mean that the training should be focused on environmental impact assessment for product development, and not just focused on environmental impact assessment in a scientific context, talking only about the calculation and the scientifically basis. For us, it is very important to focus the training in this discipline into a practical application, which is the product development, so products could be improved from an ecological point of view thanks to environmental impact assessment during the design process.

Over the last two decades, the environmental conscience has been steadily growing. Nowadays a wide range of companies have started to measure the environmental impact of their products performing Life Cycle Assessment in order to reduce it and contribute to sustainable growing. This environmental awareness has also influenced legislation, for example, the European Union has devoted several laws to introduce ecodesign measures in energy-using and energy-related products. However, although most industrial products (TVs, computers, cars...) are designed and developed by engineers, most of them have not received environmental training in their university studies. In order to teach environmental design concepts to mechanical engineering undergraduates, an environmental impact assessment tool has been created. In this paper the ECOCAD software is shown, as commercially LCA software is not prepared to be used by untrained users. ECOCAD allows students to easily analyze the influence of design decisions on the environmental impact of a component, allowing them to compare different materials (steel, aluminum, plastics... each one with different Young Modules and elastic admissible strains), calculating how the safety coefficient changes depending on the loading conditions. Also the environmental impact of manufacturing processes (stamping, plastic injection, thermoforming, die cast, extrusion....), transportation from suppliers, and to the final customers (truck, train, freight ship...), and end-of-life treatments (recycling, incineration, land-filling...) can be taken into account, allowing the students to fully understand how design decisions influence the environmental impact of a product and compare design alternatives.