Table 8-1.Current Selection Guide for GTA Welding of Common Metals
You can use table 8-1 as a guide for selecting the
NOTE: To avoid torch overheating caused by clog-
current for welding some of the more common metals.
ging and flow restrictions, you must keep the water
For more specific information, refer to the operators
manual for the specific machine you are using.
GTA welding torches are designed to conduct both
welding current and inert gas to the weld zone. The
torches can be either air or water cooled, depending on
the welding current. Air-cooled torches are used for
welding light-gauge materials at relatively low-current
settings. Water-cooled torches are recommended for
currents above 200 amperes. A sectional view of a GTA
water-cooled torch is shown in figure 8-7. When you are
using this type of torch, a circulating stream of water
flows around the torch to keep it from overheating.
Figure 8-7.GTA water-cooled torch.
The GTA welding torch carries the welding current
and directs the gas to the weld area. The torch must have
Figure 8-8.GTA torch parts.