Helium as a welding shielding gas offers unique advantages for many applications. Helium provides positive effects to most of the shielding gas mixtures used with different materials and in a variety of welding processes. Helium is an inert gas which affords more heat input to the joint, thus increasing the welding efficiency. Mixed with argon, it increases welding speed and is advantageous in penetration of thick wall aluminum, copper, and titanium materials where it compensates the high heat conduction. Drawbacks of using helium are its availability, relatively high cost and the low density. Helium can be applied in shielding as a pure gas or as a component in the shielding gas mixtures.

The objective of the thesis is to present a novel helium shielding gas recovery and recycling system devised for use in welding applications including its design and implementation. The novel system is designed by the author and it is unique in the welding shielding gas field. When using helium recovery and recycling, CO₂ emissions are reduced, and the climate change effects are decreased.

The thesis is based on i) literature analysis and ii) developing and designing the novel recovery system which is new and unique. The literature review and analysis describe welding shielding gases and their properties. The section handling helium addresses the production methods and applications, general properties, and effects of helium as welding shielding gas to the productivity and welding economy. The practical experience of the author accumulated during an extensive over 30 years career in the gas production business and the literature review has laid a foundation for the innovation and design of a novel helium recovery system. The designed system allows the recovery of helium from the welding processes. This innovation can potentially offer significant cost savings for various applications, and improve the understanding of inert gases recovery, extraction, and reuse. This approach leads to more sustainable manufacturing practices, at the same time decreasing the negative environmental impact of the production process. The review of scientific publications on the shielding gas field demonstrates that the recovery and recycling system designed by the author is new and unique. It is new in the welding sector and the thesis has undisputed research and scientific novel value.