Sustainability of unconventional machining industry considering impact factors and reduction methods of energy consumption: A review and analysis

Emergy-based sustainability measurement and evaluation of industrial production systems

The sustainability of industrial production systems is considered to be the key to promoting green transformation and upgrading of manufacturing industry. This study proposes an emergy-based method for the measurement and evaluation of the sustainability of industrial production systems. The method uses emergy as a measure, expresses all types of inputs and outputs of production systems in terms of solar emergy, and constructs indicators for the sustainable evaluation of industrial production systems that account for economic and environmental benefits from the perspectives of system functions, ecology, and sustainability. This method was applied to a disc cam machining system at a machinery company, where the user was able to quantify the sustainability of the production system and, through feedback, optimise the production process to reduce energy consumption and environmental pollution and improve the sustainability of the production process. The results show that after optimization, the emergy yield ratio of the disc cam machining system is increased from 1.45 to 4.32, the environmental load ratio is reduced by 16%, and the emergy-based sustainability index is increased by 85%. The system has long-term sustainable development capability in the future. This study provides a new theoretical perspective on sustainability assessments of industrial production systems, and our findings provide a scientific basis for guiding the sound operation and sustainable development of industrial production systems.

Re-Engineering of an Impeller for Submersible Electric Pump to Be Produced by Selective Laser Melting

The subject of the present study is the reproduction of a submersible electric pump impeller through reverse engineering and additive manufacturing. All of the phases commonly envisaged in the reproduction of an existing piece were carried out. The aim of the study is to show how the chosen pump component can be effectively re-engineered and produced with the selective laser melting technique, obtaining a final product that is comparable if not even better than the starting one. To achieve this goal, the original piece was redesigned and a new model was created and analyzed. The whole process has been split into three main phases: (i) realization of the three-dimensional model from an existing piece using reverse engineering techniques; (ii) finite element analysis for the optimization of the use of the material; and (iii) 3D printing of a concept model in polyethylene terephthalate by using the fused deposition modeling technology and of the functional model in AISI 316 stainless steel with selective laser melting technology.