05 Gouging; 06 Mechanized Torch Operation - ESAB Cutmaster 120 Manual De Instrucciones

ESAB CUTMASTER 120
NOTE!
The gas preflow and postflow are a
characteristic of the power supply
and not a function of the torch
When the shield cup is properly in-
stalled, there is a slight gap between
the shield cup and the torch handle.
Gas vents through this gap as part
of normal operation. Do not attempt
to force the shield cup to close this
gap. Forcing the shield cup against
the torch head or torch handle can
damage components.
7. Clean spatter and scale from the shield cup and
the tip as soon as possible. Spraying the shield
cup in anti - spatter compound will minimize the
amount of scale which adheres to it.
Cutting speed depends on material, thickness, and the
operator's ability to accurately follow the desired cut line.
The following factors may have an impact on system
performance:
• Torch parts wear
• Air quality
• Line voltage fluctuations
• Torch standoff height
• Proper work cable connection
4T.05 Gouging
WARNING
!
Be sure the operator is equipped
with proper gloves, clothing, eye and
ear protection and that all safety pre-
cautions at the front of this manual
have been followed. Make sure no
part of the operator's body comes in
contact with the workpiece when the
torch is activated.
Disconnect primary power to the
system before disassembling the
torch, leads, or power supply.
CAUTION
!
Sparks from plasma gouging can
cause damage to coated, painted or
other surfaces such as glass, plas-
tic, and metal.
Check torch parts. The torch parts
must correspond with the type of
operation. Refer to Section 4T.07,
Torch Parts Selection.
4T-6
OPERATION
Gouging Parameters
Gouging performance depends on parameters such
as torch travel speed, current level, lead angle (the
angle between the torch and workpiece), and the dis-
tance between the torch tip and workpiece (standoff).
CAUTION
!
Touching the torch tip or shield cup
to the work surface will cause exces-
sive parts wear.
Torch Travel Speed
NOTE!
Refer to Appendix Pages for addi-
tional information as related to the
Power Supply used.
Optimum torch travel speed is dependent on current
setting, lead angle, and mode of operation (hand or
machine torch).
Current Setting
Current settings depend on torch travel speed,
mode of operation (hand or machine torch), and the
amount of material to be removed.
Pressure Setting
Even though the setting is within the specified range,
if the torch does not pilot well the pressure may need
to be reduced.
Lead Angle
The angle between the torch and workpiece depends
on the output current setting and torch travel speed.
The recommended lead angle is 35°. At a lead angle
greater than 45° the molten metal will not be blown
out of the gouge and may be blown back onto the
torch. If the lead angle is too small (less than 35°),
less material may be removed, requiring more pass-
es. In some applications, such as removing welds
or working with light metal, this may be desirable.
Torch Head
35°
Standoff Height
Workpiece
A-00941_AB
Manual 0-5398
Gouging Angle and Standoff Distance
Standoff Distance
The tip to work distance affects gouge quality and
depth. Standoff distance of 1/8 - 1/4 inch (3 - 6
mm) allows for smooth, consistent metal removal.
Smaller standoff distances may result in a severance
cut rather than a gouge. Standoff distances greater
than 1/4 inch (6 mm) may result in minimal metal
removal or loss of transferred main arc.
Slag Buildup
Slag generated by gouging on materials such as car-
bon and stainless steels, nickels, and alloyed steels,
can be removed easily in most cases. Slag does not
obstruct the gouging process if it accumulates to the
side of the gouge path. However, slag build - up can
cause inconsistencies and irregular metal removal
if large amounts of material build up in front of the
arc. The build - up is most often a result of improper
travel speed, lead angle, or standoff height.
4T.06 Mechanized Torch Operation
Cutting With Mechanized Torch
The mechanized torch can be activated by remote
control pendant or by a remote interface device
such as CNC.
1. To start a cut at the plate edge, position the center
of the torch along the edge of the plate.
Travel Speed
Proper travel speed is indicated by the trail of the
arc which is seen below the plate. The arc can be
one of the following:
1. Straight Arc
A straight arc is perpendicular to the workpiece
surface. This arc is generally recommended
for the best cut using air plasma on stainless or
aluminum.
2. Leading Arc
The leading arc is directed in the same direction
as torch travel. A five degree leading arc is gen-
erally recommended for air plasma on mild steel.
3. Trailing Arc
The trailing arc is directed in the opposite direc-
tion as torch travel.
Manual 0-5398 OPERATION
ESAB CUTMASTER 120
D i r
e c t
i o n
o f T
o r c
h T
Standoff Distance
r a v
e l
Straight Arc
Trailing Arc
A-02586
Leading Arc
Mechanized Torch Operation
For optimum smooth surface quality, the travel speed
should be adjusted so that only the leading edge
of the arc column produces the cut. If the travel
speed is too slow, a rough cut will be produced as
the arc moves from side to side in search of metal
for transfer.
Travel speed also affects the bevel angle of a cut.
When cutting in a circle or around a corner, slowing
down the travel speed will result in a squarer cut.
The power source output should be reduced also.
Refer to the appropriate Control Module Operating
Manual for any Corner Slowdown adjustments that
may be required.
Piercing With Machine Torch
To pierce with a machine torch, the arc should be
started with the torch positioned as high as possible
above the plate while allowing the arc to transfer
and pierce. This standoff helps avoid having molten
metal blow back onto the front end of the torch.
When operating with a cutting machine, a pierce or
dwell time is required. Torch travel should not be
enabled until the arc penetrates the bottom of the
plate. As motion begins, torch standoff should be
reduced to the recommended 1/8 - 1/4 inch (3-6 mm)
distance for optimum speed and cut quality. Clean
spatter and scale from the shield cup and the tip as
soon as possible. Spraying or dipping the shield cup
in anti - spatter compound will minimize the amount
of scale which adheres to it.
4T-7