Lincoln Electric IM956 POWER WAVE C300 - Manual (Page 35)

B-14 OPERATION B-14
POWER WAVE ® C300
ALUMINUM SYNERGIC GMAW-P
(PULSED MIG)AND GMAW-PP
(PULSE ON PULSE) WELDING
The Power Wave ® C300 can produce top quality alu-
minum welds with excellent appearance, little spatter
and good bead shape. Push-pull guns are available
for consistent feeding when welding a long distance
away from the wire feeder.
PULSE-ON-PULSE WELDING
The Power Wave
® system offers both traditional pulse
and Pulse-on-Pulse™. Pulse-on-Pulse (GMAW-PP)
is an exclusive waveform for aluminum welding. Use
it to make welds with a "stacked dime" appearance,
similar to GTAW welds.( See Figure B.7)
FIGURE B.7
The pulsing frequency is adjustable. Changing the fre-
quency modulation (or arc control) of the waveform
changes the ripple spacing. Faster travel speeds may
be achieved by using higher values of frequency mod-
ulation. ( See Figure B.8 and B.9)
FIGURE B.8
Frequency Modulation = -10
Wide weld and ripple spacing, slow travel speed.
Frequency Modulation = 10
Narrow weld and ripple spacing, fast travel speed.
FIGURE B.9
ALUMINUM GMAW-P AND GMAW-PP
ALUMINUM PULSE WELDING
Synergic GMAW-P (Pulsed MIG) welding is ideal for
low spatter, out of position and reduced heat input
applications. During pulse welding, the welding cur-
rent continuously switches from a low level to a high
level and then back again. Each pulse sends a small
droplet of molten metal from the wire to the weld pud-
dle.
Pulse welding controls the arc length with 'Trim'
instead of voltage. When trim (arc length) is adjusted,
the Power Wave
® automatically recalculates the volt-
age, current and time of each part of the pulse wave-
form for the best result. Trim adjusts the arc length
and ranges from 0.50 to 1.50, with a nominal value of
1.00 for a 3/4" (19mm) electrode stick-out. Trim values
greater than 1.00 increase the arc length, while values
less than 1.00 decrease the arc length.
(See Figure B.10)
FIGURE B.10