Lincoln Electric IM348 AC-225-GLM - Manual (Page 20)

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These electrodes are used for general purpose all-position
fabrication and repair welding; also the best choice for pipe
welding and sheet metal butt, corner and edge welds. They
can be used for repair work when dirt, grease, plating or
paint cannot be completely cleaned from the steel.
Typically used with motions “A’’ and “B’’ (below) for the
first pass on vertical-up welds.
High-Deposit Group (E6027, E7024)
This group includes the heavy coated, iron powder elec-
trodes with their soft arc and fast deposit rates. These elec-
trodes have a heavy slag and produce exceptionally smooth
beads. They are generally used for production welding
where all work can be positioned for downhand welding.
Stringer beads, with drag technique, are always preferred
over weave passes with these electrodes.
High-Speed Group (E6012, E6013, E7014)
This group includes electrodes which have a moderately
forceful arc and deposit rates between those of the out-off
position and high-deposit electrodes. They are primarily
general purpose production electrodes especially for down-
hill fillets and laps or short and irregular welds that change
direction or position. Also widely used in maintenance and
recommended for sheet metal fillet and lap welds. Motion
“D’’ (below) is generally used for vertical-up welding, but
motions “A” and “B” are also suitable.
Low Hydrogen Group (E7018, E7028)
These electrodes are generally called “low hydrogen.” The
name comes from the fact that their coating contains little
hydrogen in either moisture or chemical form. Low hydro-
gen electrodes offer these benefits: outstanding crack resis-
tance, lowest porosity on sulphur bearing steels, and capa-
ble of X-ray quality deposits. Thus, they are the first choice
when welding “problem” steels. E7018 can be used in all
positions, with Motion “C” recommended for the first pass
on vertical-up welds. NEVER use a whipping technique or
a long arc with these electrodes. ALWAYS fill craters by
drawing electrodes away slowly. ALWAYS keep these elec-
trodes dry. Electrodes not used within a few hours after a
container is opened must be stored in heat cabinets. LH-73
is recommended with the AC-225-GLM. Normally, DC(+)
is preferred for these electrodes.
Motions
Manipulation depends on the joint. Some of the common
motions are shown above.
Motion “A” is a straight whipping motion used with fast-
freeze electrodes to make stringer beads in all positions and
on all types of joints. It keeps the molten pool small and lets
it freeze quickly so the weld metal doesn’t spill down or
through the joint. Keep arc short when in the crater and
longer during whip out from the crater.
Motion “B” is a whipping motion combined with a slight
weave in the crater. It is used with fast-freeze electrodes as
the first pass on vertical fillets and V-butts.
Motion “C” is a simple side-to-side weave used with all
types of electrodes to make fill passes on vertical fillets and
V-butts. Also sometimes used with fill-freeze and low
hydrogen electrodes to make the first pass on these joints.
Motion “D” is a triangular weave used with fill-freeze and
low hydrogen electrodes to make one pass vertical fillets
and V-butts. It results in a larger weld than Motion “C’’.
Motion “E” is a box weave used with all types of elec-
trodes to make fill passes on vertical fillets and V-butts. It
is similar to Motion “C,’’ but with a distinct pause and
slight upward motion at each edge of the weld to assure
complete crater filling and elimination of undercut.
Motion “F” is a circular motion used with all types of elec-
trodes to make overhead welds. Sometimes accompanied
by a slight whip after each oscillation in the crater. Always
use a series of stringer beads overhead; do not weave.
Motion “G” is a simple side-to-side weave used with all
electrodes on wide fillets or butts in the flat position.