MetFab - Welding Fume Handbook - Flipbook - Page 23
8 Effect of shielding gas: particulate fume
5.9
I
6
5
I
4
I
4.9
4.9
3.1
3
I
2
I
1
I
Fume emission rate mg/s
5.4
0
98% Ar/2% CO
Inomaxx® 2
Inomaxx® Plus
65% Ar/33% He
2% CO
7.5% Ar/90% CO
2.5% CO
shielding gas
Figure 12: The effect of shielding gas on fume emission rate
during MAG welding of stainless steel with dip transfer
The differences in emission rate are small, and there is
no clear correlation between the formulation and fume
emission rate. Again, there seems to be no health advantage
in choosing one gas compared to another.
FCAW
Tests comparing carbon dioxide and a three-component
mixture containing helium showed that for many welding
conditions the helium mixture generated somewhat less
fume. However, under optimum conditions the two shielding
gases provided very similar results (Figure 13).
0.5
CO
I
0.4
I
0.3
I
0.2
35% Ar/ 50% He/ 15% CO
I
0.1
0
I
Fume emission rate mg/s
I
0.6
I
20
I
25
I
30
I
35
I
40
Arc voltage
Figure 13: The effect of shielding gas formulation on fume
emission rate during FCAW of stainless steel
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