Efficacy Assessment of Wire Cleaning and Lubrification on MIG/MAG Feedability

Abstract

The efficacy of a cleaning and lubrication kit for welding wires was analysed in relation to the wire feedability in MIG/MAG process. Comparative bead-on-plate welds on flat position were carried out, using different contact tips, as well as different wire surface conditions (normal and non-conforming, oxidized and contaminated with debris). A dedicated system, consisting of a load cell assisted by a voltage drop sensor for the contact tip, was used to qualify the feedability. The effectiveness of the kit was verified by the variation of the contact tip electric resistance and the feeding force, as well as by the visual appearance of the wire without arc . The “kit” showed to be effective, reducing the feeding force without increasing the electrical resistance of the contact tip. However, it was not effective when applied over oxidized wires. It is concluded that the kit is effective in cases where the wire is in normal use or only contaminated with debris, reducing the wire-torch friction and facilitating wire feedability, but it is not sufficient to correct serious anomalies of the wire (oxidation).

Key-words:
GMAW; Automation; Wire feedability; Operational improvements