Lincoln Electric 125 Operator's Manual page 18

WIRE FEEDER WELDERS (125, 140)
B. INSTALL SHIELDING GAS
MIG welding requires an appropriate bottle of shielding gas. For
mild steel a cylinder of Ar/CO
2
the following instructions to properly connect shielding gas to the
machine.
CYLINDER may explode if damaged. Keep
cylinder upright and chained to support
• Keep cylinder away from areas where it
may be damaged.
• Never lift welder with cylinder attached.
• Never allow welding electrode to touch
cylinder.
• Keep cylinder away from welding or
other live electrical circuits.
BUILDUP OF SHIELDING GAS may harm
health or kill.
• Shut off shielding gas supply when not
in use.
1. Secure the cylinder to a wall or other stationary support
to prevent the cylinder from falling over. Insulate the
cylinder from the work circuit and earth ground. Refer to
Figure B.13.
2. With the cylinder securely installed, remove the cylinder
cap. Stand to one side away from the outlet and open the
cylinder valve very slightly for an instant. This blows
away any dust or dirt which may have accumulated in
the valve outlet.
BE SURE TO KEEP YOUR FACE AWAY FROM THE VALVE OUT-
LET WHEN "CRACKING" THE VALVE. Never stand directly in
front of or behind the flow regulator when opening the cylin-
der valve. Always stand to one side.
or 100% CO can be used; refer to
2
WARNING
WARNING
WARNING
3. Attach the flow regulator to the cylinder valve and tighten the
union nut securely with a wrench.
NOTE: If connecting to 100% CO
adapter is required. Purchase separately S19298 CO
be sure to install plastic washer included in the fitting on the
bottle side.(See Figure B.13 )
4. Refer to Figure B.13. Attach one end of inlet gas hose to the
outlet fitting of the flow regulator and tighten the union nut
securely with a wrench. Connect the other end to the machine
Solenoid Inlet Fitting (5/8-18 female threads — for CGA — 032
fitting). Make certain the gas hose is not kinked or twisted.
SHIELDING GAS
1. For CO , open the cylinder very slowly. For argon-mixed gas,
2
open cylinder valve slowly a fraction of a turn. When the cylin-
der pressure gauge pointer stops moving, open the valve fully.
2. Set gas flow rate for 30 to 40 cubic feet per hour (14 to 18
L/min) under normal conditions. Increase to as high as 40 to 50
CFH (18 to 23.5 L/min) for out of position welding.
3. Keep the cylinder valve closed, except when using the
machine.
B 8
OPERATION
FIGURE B.13
MALE END
REGULATOR
ADAPTER
PLASTIC
WASHER
CO
2
100%
FEMALE END
75/25
MIXES
cylinder, a CO regulator
2 2
2
S19298
adapter,