Lincoln Electric IM366-B Manuale Utente

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16

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The cored wire melts in the arc and tiny droplets of
molten metal shoot across the arc into the molten
pool. The wire sheath provides additional filler metal
for the joint to fill the groove or gap between the two
pieces of the base metal.

The core materials also melt or burn in the arc and
perform several functions. They make the arc stead-
ier, provide a shield of smoke-like gas around the arc
to keep oxygen and nitrogen in the air away from the
molten metal, and provide a flux for the molten pool.
The flux picks up impurities and forms the protective
slag on top of the weld during cooling.

After running a weld bead, the slag may be removed
with a chipping hammer and wire brush. This
improves appearance and allows for inspection of the
finished weld.

Since machine size and output characteristics limit the
size and type of wire electrode which can be used,
Lincoln .035" (0.9 mm) NR-211-MP Innershield elec-
trode is recommended for Self-Shielded Flux Cored
Arc Welding with the SP-100.

1. See page 6, “Recommended Processes and

Equipment” for selection of welding wire and shield-
ing gas, and for range of metal thicknesses that can
be welded.

2. See the “Welding” chart on the inside of wire feed

section door for information on setting the controls.
(Also on page 23 of this manual.)

3. Set the “Voltage” and “Wire Speed” controls to the

settings suggested on the chart for the welding wire
and base metal thickness being used. The voltage
control is marked “V” and the wire feed speed is
marked “olo.”

4. Check that the polarity is correct for the welding

wire being used. Set the polarity for DC– when
welding with NR-211-MP Innershield electrode.
(See installation instructions on page 9 on how to
make output polarity connection.)

5. When using Innershield electrode, the gasless noz-

zle may be used instead of a gas nozzle to give
improved visibility.

6. Connect work clamp to metal to be welded. Work

clamp must make good electrical contact to the
workpiece. The workpiece must also be grounded
as stated in “Arc Welding Safety Precautions” sec-
tion of this manual.

Four simple manipulations are of prime importance.
With complete mastery of the four, welding will be
easy.

Illustrated below is the correct welding position for
right-handed people. (For left-handed, it is opposite.)

Hold the gun (of the gun and cable assembly) in your
right hand, and hold the hand shield with your left
hand. (Left handers simply do the opposite.)

When using the self-shielded FCAW process, weld
from left to right (if you are right handed). This enables
you to clearly see what you are doing. (Left handers
do the opposite.) Tilt the gun toward the direction of
travel holding the electrode at an angle as shown
below.

1. Be sure the work clamp makes good electrical con-

tact to the work.

2. Position gun over joint. End of wire may be lightly

touching the work.

3. Position faceshield to protect face and eyes, close

gun trigger, and begin welding. Hold the gun so that
the contact tip to work distance is about 3/8 to 1/2
inch (10 to 12 mm).

4. To stop welding, release the gun trigger and then

pull the gun away from the work after the arc goes
out.

5. A ball may form at the tip end of the wire after weld-

ing. For easier restrikes (with Innershield wire), the
ball may be removed by feeding out a few inches of
wire and simply bending the wire back and forth
until it breaks off.

6. When no more welding is to be done, turn off the

machine.

Burning of core materials
inside wire electrode
results in shield of gas.

Arc stream

Base metal

Weld metal

Protective slag

Cored wire

Molten pool

ARC RAYS can burn eyes and skin.
• When using an open arc process, it is

necessary to use correct eye, head
and body protection.

• Protect yourself and others; read the

section on Arc Burn at the front of this manual.

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