Firepower FP 125 Operating Manual & Installation Manual page 30

FIREPOWER FP 125,135,165
When changing to a different electrode wire diameter, different control settings are required. A thinner electrode wire needs more wire
speed to achieve the same current level.
A satisfactory weld cannot be obtained if the wire speed and voltage switch settings are not adjusted to suit the electrode wire diam-
eter and dimensions of the work piece.
If the wire speed is too high for the welding voltage, "stubbing" will occur as the wire dips into the molten pool and does not melt.
Welding in these conditions normally produces a poor weld due to lack of fusion. If however, the welding voltage is too high, large drops
will form on the end of the electrode wire, causing spatter. The correct setting of voltage and wire speed can be seen in the shape of
the weld deposit and heard by a smooth regular arc sound.
GAS METAL ARC WELDING (GMAW)
This process, also known as MIG welding, CO2 welding, Micro Wire Welding, short arc welding, dip transfer welding, wire welding etc.,
is an electric arc welding process which fuses together the parts to be welded by heating them with an arc between a solid, continu-
ous, consumable electrode and the work. Shielding is obtained from an externally supplied gas or gas mixture. The process is normally
applied semi-automatically; however the process may be operated automatically and can be machine operated. The process can be
used to weld thin and fairly thick steels, and some non-ferrous metals in all positions.
FLUX CORED ARC WELDING (FCAW)
This process also known as Open arc, Innershied, FAB Shield, etc., is an electric arc welding process which fuses together the parts
to be welded by heating them with an arc between a continuous flux filled electrode wire and the work. Shielding is obtained through
decomposition of the flux within the tubular wire. The process is normally applied semi-automatically; however the process may be
applied automatically or by machine. It is commonly used to weld large diameter electrodes in the flat and horizontal position and small
electrode diameters in all positions. The process is used to a lesser degree for welding stainless steel and for overlay work.
WARNING
!
Follow these instructions only after referring to the Safety Instructions and Warnings chapter of this manual,
and the instructions in the Installation chapter. .
Check List Before Starting
POLARITY – DCEP (Direct Current Electrode Positive) or DCEN (Direct Current Electrode Negative)
WIRE FEED SPEED – 1 to 10
VOLTAGE RANGE SWITCH SETTING – 1 to 4 for FP 135, 165 an two switches and1-2 and Low-High for FP 125.
GAS FLOW RATE – 15 to 25 CFH (If shielding gas is required)
ELECTRODE WIRE STICK-OUT – approx 3/8" (10mm)
OPERATION
Shielding Gas
Weld Metal
Solidified Weld
Metal
Figure 4-3: GMAW Process
Gas (optional)
Molten Metal
Solid Weld
Metal
Molten
Slag Slag
Figure 4-4: FCAW Process
4-4
Nozzle
Electrode
Arc
Base Metal
Art: A-05103
Nozzle (optional)
Flux Cored
Electrode
Arc
Art: A-05104
Manual 0-5123