pipe to avoid penetrating the root opening or pushing it into the tungsten,
which can contaminate the weld.
Note that the technique for cup
walking is slightly different on fill and
cap passes compared with the root
pass. For the fill pass, make a three-point contact with the groove instead
of a two-point contact, pivoting the
torch so that the edges of the groove
guide it. For the cap pass, make a single
point of contact, pivoting the torch
carefully on the weld face while moving
To prevent weld contamination,
maintain adequate postflow after
each pass. One second of postflow for
every 10 amps of welding current
generally is adequate.
TALK THE TALK,
WALK THE WALK
Cup walking provides several benefits.
In many cases it is faster than conven-
tional welding techniques. It can also be
a more comfortable process for welders
and offer better torch control. However,
the main reason to use cup walking
is quality. Using this technique, while
keeping in mind austenitic stainless
steels’ tendency to distort and shrink
when subjected to too much heat, can
help you to make quality welds.
Brent Williams is the marketing manager of TIG solutions, Miller Electric Mfg.
Co., and a technical contributor for
Weldcraft, 2741 N. Roemer Road,
Appleton, WI 54911, 920-882-6800,