Design of a compressed air system is a complex issue, involving the design of structures formed by the air sources, air receptors and

installations connecting all structure components. Another major task is to ensure the required quality of compressed air. The paper briefly

outlines the methodology of integrated and network structure design, using an objective function to find the optimal solution. In terms of

quality assurance, the technological aspects of compressed air generation, treatment and distribution are defined.

The material selected for this investigation was low alloy steel weld metal deposit (WMD) after MAG welding with micro-jet cooling. The

present investigation was aimed as the following tasks: analyze impact toughness of WMD in terms of micro-jet cooling parameters. Weld

metal deposit (WMD) was first time carried out for MAG welding with micro-jet cooling of compressed air and gas mixture of argon and

air. Until that moment only argon, helium and nitrogen and its gas mixture were tested for micro-jet cooling