Lincoln Electric MAGNUM IM632-B - Manual (Page 10)

The wire feeder drive roll pressure should be set to a
minimum to prevent wire from coming thru the cable
when a wire feed stop occurs. The ideal drive roll
pressure is set so the drive rolls will slip when the
electrode is slightly wavy after a wire feed stop.
ELECTRODES AND EQUIPMENT
The MAGNUM®™ 450WC & 650WC guns and cables
have been designed for use with Lincoln L-50 and
Super Arc L-56, solid steel wire electrodes for the
GMAW process and Lincoln Outershield® cored elec-
trodes for the gas-shielded FCAW process. Refer to
the appropriate Lincoln Process and Procedure
Guidelines for the electrode used for information on
recommended electrical and visible stickouts.
MAKING A WELD
Note: Water cooled guns will have a higher voltage
drop along the length of the cable than air cooled
guns. To compensate for the higher voltage drop, the
following table is a guide line to determine how much
the welding voltage should be increased.
Welding Current Welding Voltage Increase Welding Voltage Increase
For MAGNUM® 450WC
For MAGNUM® 650WC
Compared to MAGNUM® 400 Compared to MAGNUM®
550
200 amperes
0.5 volts 0.5 volts
300 amperes 1.0 volts 0.7 volts
400 amperes 1.5 volts 0.9 volts
500 amperes ------ 1.2 volts
600 amperes ------ 1.4 volts
650 amperes ------ 1.6 volts
The final voltage setting must be determined by the
arc characteristics that are required for the welding
process.
ELECTRIC SHOCK can kill.
•
Do not touch electrically live parts or
electrode with skin or wet clothing.
• Insulate yourself from work and ground.
FUMES AND GASES can be dangerous.
•
Keep your head out of fumes.
• Use ventilation or exhaust to remove
fumes from breathing zone.
WELDING SPARKS can cause fire or
explosion.
•
Keep flammable material away.
ARC RAYS can burn.
•
Wear eye, ear and body protection.
B-1 OPERATION B-1
a) Check that the welding power source is on and that
the shielding gas supply is set for the proper flow
rate.
b) Position electrode over joint. The end of the elec-
trode should be slightly off the work.
c) Lower your welding helmet, close the gun trigger,
and begin welding. Hold the gun so the contact tip
to work distance gives the correct electrical stickout
as required for the procedure being used.
d) To stop welding, release the gun trigger and then
pull the gun away from the work after the arc goes
out.
AVOIDING WIRE FEEDING PROBLEMS
Wire feeding problems can be avoided by observing
the following gun handling procedures:
a) If a 'burn back' or wire feed stop occurs, release the
trigger immediately. Remove the contact tip, free
the wire and clean or replace the tip as necessary.
If the wire has been scored by the feed rolls, dis-
card the damaged section of the wire. This is nec-
essary because the damaged wire could jam in the
contact tip and cause another burn back.
b) Do not kink or pull cable around sharp corners.
c) Keep the electrode cable as straight as possible
when welding or loading electrode through cable.
d) Avoid wrapping excess cable around handle or
front of wire feeder.
e) Do not allow dolly wheels or trucks to run over
cables.
f) Keep cable clean by following maintenance instruc-
tions.
g) Use only clean, rust-free electrode. The Lincoln
electrodes have proper surface lubrication.
h) Replace contact tip when the arc starts to become
unstable or the contact tip end is fused or
deformed.
i) When using aluminum electrodes, 10 ft. Maximum
cable length is recommenced. If longer cable
lengths are used, cable should be kept as straight
as possible.
MAGNUM® 450WC & 650WC
WARNING