Life Cycle Assessment (LCA) Results of MIG and TIG Welding Technologies Using the IMPACT 2002+ Methodology

Abstract

The aim of this LCA studies is to investigate the potential environmental impacts of arc welding technologies such as Metal Inert Gas (MIG), Tungsten Inert Gas (TIG) processes that follows the framework, principles, requirements, and guidelines given by the International Organisation for Standards (ISO). For a 1 m of welding activities, LCA studies have been carried out in accordance with cradle to gate system boundary employing the SimaPro LCA application tool and the ecoinvent version 3.6 database and applying the comprehensive life cycle impact assessment (LCIA) methodology IMPACT 2002+, version 2.14 that translates the input and output inventory data into the environmental impacts. From the evaluation of LCIA results, it has been demonstrated that the TIG welding process showed higher environmental impacts than the MIG welding process, in midpoint impact categories such as global warming potential, aquatic acidification, ozone layer depletion, and aquatic eutrophication. This mainly occurred due to the slower welding speed of the TIG welding process which results in higher shielding gas and electrical energy consumption. Endpoint damage categories such as human health, climate change, ecosystem quality, and resources have also been investigated for both welding processes. Finally, it is demonstrated from LCIA results that the overall environmental footprint of TIG welding process is about 1.3 times higher than that of MIG welding process