Status of environmental life cycle assessment in manual metal arc welding (MMAW) processes

Abstract

Introduction: welding is currently one of the most important manufacturing processes in the manufacturing sector, as it joins two or more parts by heating or by casting processes, applying pressure or not. The purpose of manufacturing by welding processes is to join materials to meet requirements or service needs without involving excessive costs, negative environmental implications, or adverse effects on workers. This is why the life cycle assessment (ACV) is a methodology applied at the engineering level to evaluate the different environmental impacts of welding technologies. This methodology has been applied in manual metal arc welding processes (MMAW), where the excessive consumption of resources such as electrodes and energy needed to melt the consumables contribute to the generation of negative environmental impacts, being potential processes of global warming, photochemical ozone creation and eutrophication. To investigate the progress in the state of the art of environmental life cycle Objective: assessments in MMAW welding processes. Results: the results of the environmental life cycle analysis indicate that, for a weld bead of 1 meter in length using the MMAW process, a greater amount of resources are consumed, such as filler materials and electrode coatings, in addition to a greater consumption of electrical energy by the welding machine, which contributes to environmental impacts comparatively greater than those generated in other welding processes. Conclusions: it was concluded that low welding speed and high deposition rate lead to high welding times in MMAW processes, consequently, low productivity and excess resources generate a greater impact to the environment.