MetFab - Air Products Welder's Handbook - Flipbook - Page 21
Torches
TIG torches are rated according to the
current they can carry without overheating.
At currents typically above 250A, the torch
body and possibly the nozzle are water
cooled. At lower currents, the flow of the
weld process gas provides sufficient cooling.
Semi-automatic torch
A torch with a gas lens provides
a laminar gas flow allowing the
electrode to be set further out from
the end of the nozzle giving better
visibility of the arc and weld pool
whilst maintaining the proper shield.
Manual
(scratch start) torch
Torch body
Gas lens
Ceramic gas nozzle
Tungsten electrode
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