Thick Sections Of Metal; Suggestions For Extra Utility From The Pro-Cut System - Lincoln Electric PRO-CUT SVM146-A Service Manual

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THICK SECTIONS OF METAL

Torch Standoff
1/8" thru 3/16"
Standoff
Output set above 45 Amps.
• The best quality and consumable life will be
obtained by holding the torch off the surface about
3/16 in. (4.7mm). Too long an arc may compromise
cut quality and consumable life. The nozzle should
NOT be dragged on the work.
• Use of the S22151 Drag Cup will maintain the prop-
er standoff. The only time not to use the drag cup
when the output control is set above mid-range is in
special, tight corners. Always hold at least a 1/8 in.
(3.2mm) standoff in those situations.
• If piercing is required, slowly lower the torch at an
angle of about 30° to blow the dross away from the
torch tip and slowly rotate the torch to a vertical
position as the arc becomes deeper. This process
will blow a lot of molten metal and dross. Be care-
ful! Blow the dross away from the torch, the opera-
tor and any flammable objects.
• Where possible, start the cut from the edge of the
workpiece.
• Keep moving! A steady speed is necessary. Do not
pause.
• Do not allow the torch cable or body to contact a
hot surface.
SUGGESTIONS FOR EXTRA UTILITY
FROM THE PRO-CUT SYSTEM
WARNING
ELECTRIC SHOCK can kill.
• Turn off machine at the disconnect
switch on the front of the machine
before tightening, cleaning or replac-
ing consumables.
OPERATION
Machine Output Setting
45
Output Setting
Mid. thru Max. Range
PRO-CUT 80
1. Occasionally an oxide layer may form over the tip
of the electrode, creating an insulating barrier
between the electrode and nozzle. This will result in
the tripping of the Pro-Cut's safety circuit. When
this happens, turn the power off, remove the noz-
zle and electrode and use the electrode to rub
against the inside bottom surface of the nozzle.
This will help remove any oxide buildup. Replace
the nozzle, turn on the power and continue cutting.
If the Parts-in-Place circuit (safety status indicator
light) continues to trip after cleaning the consum-
ables, replace them with a new set. Do not contin-
ue to cut with excessively worn consumables as
this can cause damage to the torch head and will
degrade cut quality.
2. To improve consumable life, here are some sug-
gestions that may be useful:
a. Never drag the nozzle on the work surface if
the output control knob is above 45 Amps.
b. Make sure the air supply to the Pro-Cut is
clean and free of oil. Use several extra in-line
filters if necessary.
c. Use the lowest output setting possible to
make a good quality cut at the desired cut
speed.
d. Minimize dross buildup on the nozzle tip by
starting the cut from the edge of the plate
when possible.
e. Pierce cutting should be done only when nec-
essary. If piercing, angle the torch about 30°
from the plane perpendicular to the work-
piece, transfer the arc, then bring the torch
perpendicular to the work and begin parallel
movement.
f. Reduce the number of pilot arc starts without
transferring to the work.
g. Reduce the pilot arc time before transferring to
the work.
h. Set air pressure to recommended setting. A
higher or lower pressure will cause turbulence
in the plasma arc, eroding the orifice of the
nozzle tip.
i. Use only Lincoln consumable parts. These
parts are patented. Using any other replace-
ment consumables may cause damage to the
torch or reduce cut quality.
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