©
COPYRIGHT 2000 THE ESAB GROUP, INC. LESSON
V 5.12.2
Arcaloy
lime coated
electrodes were
among the earliest stainless steel elec- trodes
developed in the United States. Designed for welding with direct current,
reverse polarity
only, the coating contains considerable amounts of limestone and fluorspar producing
a fast freezing slag that facilitates
welding in the vertical and overhead positions. The weld
bead is slightly convex and moderately
rippled. (See Figure 15). 5.12.2.1
Characterized by a strong globular
arc, a moderate amount of spatter and slag removal
that is somewhat difficult, the lime type is not the most popular with the welding
opera- tors. However,
it is the easiest to use stainless electrode for out-of-position welding. Also,
the convex bead
can provide the necessary margin of safety in highly stressed joints in many
cases. 5.12.3
Arcaloy
AC-DC
Titania coated
electrodes were
the first such electrodes to receive
wide acceptance in this country. Designed to operate on alternating current
as well as direct
current, the coating contains dominant amounts of rutile (titania), medium amounts
of limestone,
and limited amounts of fluorspar. By far, the AC/DC type is the most popular
of the coated
stainless electrodes. Welders like to use it because of the smoother arc
action, low amount
of fine spatter and easy slag removal. Also, the bead is relatively flat,
finely rippled and has
good side-wall fusion (See Figure 15). Although used in all positions, vertical
and over- head
welding requires slightly more operator skill than with the lime types because
the slag does
not freeze as quickly. 5.12.4
Arcaloy
"Plus" electrodes
display characteristics not found in the conventional
lime and AC-DC Titania coatings. Designed
to operate on DCEP or AC, this coating is specially
formulated to operate on a broad range of current settings, and most significantly,
these electrodes perform their best
at high heat inputs where conventional AC-DC electrodes tend
to break down. 5.12.4.1
When operating at high currents, Arcaloy
Plus electrodes deposit weld metal at exceptional
speeds with a smooth spray transfer. The bead profile is finely rippled,
concave, and evenly
feathered (See Figure 15). Spatter is minimal. The molten slag
does not edge into
the weld puddle, thereby assuring easy visibility of the arc transfer.
5.12.4.2 Arcaloy
Plus electrodes were developed for applications on dairy and food pro-
cessing equipment and chemical containers,
to name a few, where the weld radius must be smooth
and concave to prevent particle entrapment. When welding in the flat and
horizontal fillet
positions, the concave deposit and absence of surface irregularities make it ideal
for applications
where cosmetic appearance, speed, and final finishing are factors.
