MetFab - Welding Fume Handbook - Flipbook - Page 21
8 Effect of shielding gas: particulate fume
7
I
6
I
5
I
6.7
5.5
5.0
4.5
4
I
3
I
2
I
1
I
Fume emission rate mg/s
I
8
95% Ar/5% CO
4.4
4.2
98% Ar/2% CO
93% Ar/5% CO/2%O
Ferromaxx® 7
92% Ar/8% CO
Ferromaxx® 15
Figure 9: The effect of shielding gas on fume emission rate
during MAG welding of mild steel with dip transfer
25
29.2
I
20
I
15
12.2
9.2
I
10
I
Fume emission rate mg/s
I
30
6.7
6.9
I
5
13.4
95% Ar/5% CO
98% Ar/2% CO
93% Ar/5% CO/2%O
Ferromaxx® 7
92% Ar/8% CO
Ferromaxx® 15
Figure 10: The effect of shielding gas on fume emission rate
during MAG welding of mild steel with spray transfer
For each shielding gas, spray transfer gives higher fume
emission rates than dip transfer. For a given transfer mode,
however, the choice of shielding gas has relatively little effect
on fume emissions.
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