Comparing Environmental Impacts of Additive Manufacturing vs. Investment Casting for the Production of a Shroud for Gas Turbine

Abstract

Additive manufacturing (AM hereinafter) is revolutionizing prototyping production and even small-scale manufacturing. Usually it is assumed that AM has lower environmental impact, compared to traditional manufacturing processes, but there have been no comprehensive environmental life-cycle assessment studies confirming this, especially for the gas turbines (GT hereinafter) and turbomachinery sector. In this study the core processes performed at Baker Hughes site in Florence are considered, together with the powder production via atomization process to describe the overall environmental impact of a GT shroud produced through additive manufacturing and comparing it with traditional investment casting production process. Particular attention is given to materials production and logistics. The full component life cycle starts from the extraction of raw materials during mining, their fusion and, as said, the atomization process, the powders are transported to the gas turbines production site where they are used as base material in additive manufacturing, also machining and finishing processes are analyzed as they differ for a component produced by AM respect to one produced by traditional investment casting. From the analysis of the data obtained, it emerges that the AM process has better performances in terms of sustainability than the Investment casting (IC hereinafter), highlighted above all by a decrease in greenhouse gas emissions (GHG hereinafter) of over 40%.