Henry Moore: Sculptor and Humanist

Fume formation from spatter oxidation during arc welding

“…For GMAW with mild and stainless steel wire of 1 . 2 mm diameter, the literature 2,[10][11][12][13][14][15][16] reports that fume formation rates can increase from approximately 0 . 05 g min 21 to approximately 0 .…”

“…The slowest droplets (and therefore the least affected by convective cooling) moved at 0 . 2 m s 21 , so this value was used conservatively for the velocity in equation (2).…”

“…Both spatter and fume formation rates increase and decrease in a similar way as welding parameters change. 1 Although the cause for, and the amount of, spatter ejection may differ between the various arc welding processes (for example, gas metal arc welding (GMAW) utilises a consumable electrode from which spatter droplets can violently detach, whereas gas tungsten arc welding (GTAW) does not), welding spatter itself, which is nothing more than liquid metal droplets, is essentially the same regardless of welding process. If the welding process uses flux or slag, that material may also contribute to spatter, in addition to that formed from the weld metal.…”

“…Therefore, it would contribute to the overall amount of respirable particulate, thus increasing the amount of welding 'fume' collected. [2][3][4] However, Zimmer et al 5 measured the concentration of respirable (in the size range of 1-20 mm) particles formed during welding and concluded that microspatter formation does not significantly contribute to fume formation rates.…”

“…Other researchers attributed the fume-spatter relationship to spatter oxidation. 1,6,7 They hypothesised that the greater fume formation rate observed during globular welding conditions is caused by vapour formed from combusting spatter droplets. This was concluded after finding spatter particles that were porous and apparently oxidised.…”