03 General Cutting Information - ESAB Cutmaster 120 Operating Manual

ESAB CUTMASTER 120
Bevel Angle
The angle between the surface of the cut edge and
a plane perpendicular to the surface of the plate.
A perfectly perpendicular cut would result in a 0°
bevel angle.
Top - Edge Rounding
Rounding on the top edge of a cut due to wearing
from the initial contact of the plasma arc on the
workpiece.
Bottom Dross Buildup
Molten material which is not blown out of the cut area
and resolidifies on the plate. Excessive dross may
require secondary cleanup operations after cutting.
Kerf Width
The width of the cut (or the width of material removed
during the cut).
Top Spatter (Dross)
Top spatter or dross on the top of the cut caused by
slow travel speed, excess cutting height, or cutting
tip whose orifice has become elongated.
4T.03 General Cutting Information
WARNING
!
Disconnect primary power at the
source before disassembling the
power supply, torch, or torch leads.
Frequently review the Important
Safety Precautions at the front of
this manual. Be sure the operator is
equipped with proper gloves, cloth-
ing, eye and ear protection. Make
sure no part of the operator's body
comes into contact with the work-
piece while the torch is activated.
CAUTION
!
Sparks from the cutting process can
cause damage to coated, painted,
and other surfaces such as glass,
plastic and metal.
NOTE!
Handle torch leads with care and
protect them from damage.
4T-2
Piloting
Piloting is harder on parts life than actual cutting
because the pilot arc is directed from the electrode
to the tip rather than to a workpiece. Whenever
possible, avoid excessive pilot arc time to improve
parts life.
Torch Standoff
Improper standoff (the distance between the torch tip
and workpiece) can adversely affect tip life as well as
shield cup life. Standoff may also significantly affect
the bevel angle. Reducing standoff will generally
result in a more square cut.
Edge Starting
For edge starts, hold the torch perpendicular to the
workpiece with the front of the tip near (not touching)
the edge of the workpiece at the point where the cut
is to start. When starting at the edge of the plate, do
not pause at the edge and force the arc to "reach"
for the edge of the metal. Establish the cutting arc
as quickly as possible.
Direction of Cut
In the torches, the plasma gas stream swirls as it
leaves the torch to maintain a smooth column of
gas. This swirl effect results in one side of a cut be-
ing more square than the other. Viewed along the
direction of travel, the right side of the cut is more
square than the left.
Left Side
Cut Angle
Side Characteristics Of Cut
To make a square - edged cut along an inside
diameter of a circle, the torch should move coun-
terclockwise around the circle. To keep the square
edge along an outside diameter cut, the torch should
travel in a clockwise direction.
Dross
When dross is present on carbon steel, it is com-
monly referred to as either "high speed, slow speed,
or top dross". Dross present on top of the plate is
normally caused by too great a torch to plate dis-
tance. "Top dross" is normally very easy to remove
OPERATION
Right Side
Cut Angle
A-00512
300X5398