Table 8-4.Selection of Shielding Gases for Various GMAW and GTAW Applications
gas that moves up the tube, the higher the ball is lifted.
pressure. If you use higher inlet pressures, the gas flow
Figure 8-11 shows a cross section of the flowmeter.
rate will be higher than the actual reading. The reverse
is true if the inlet pressure is lower than 50 psig; there-
The shielding gas regulator has a constant outlet
fore, it is important to use accurately adjusted regulators.
pressure to the flowmeter of about 50 psig. This is
With an accurate flowmeter, these regulators can deliver
important because the flowmeter scales are accurate
inert gas flows up to 60 cfh. You should read the scale
only if the gas entering them is at that approximate
by aligning the top of the ball with the cfh desired.