Tweco PAK Master 150XL - Manual (Page 34)

OPERATION 4-6 Manual 0-2864
Cut Surface
The condition (smooth or rough) of the face of the
cut.
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 work-
piece.
Dross Build-up and Top Spatter
Dross is molten material which is not blown out of
the cut area and re-solidifies on the plate. Top spat-
ter is dross which accumulates on the top surface of
the workpiece. Excessive dross may require second-
ary clean-up operations after cutting.
Kerf Width
The width of material removed during the cut.
Nitride Build-up
Nitride deposits which may remain on the surface of
the cut when nitrogen is present in the plasma gas
stream. Nitride buildups may create difficulties if
the material is welded after the cutting process.
Cut Quality on Various Materials
Types of Material
Type of Gases Material Thickness Carbon Steel Stainless Aluminum
Air Plasma and Gage (0.5 mm) Excellent Good-Excellent Good-Excellent
Air Secondary Gage to 1 inch (0.5 mm - 25.4 mm) Excellent Good Good
1 to 1-1/2 inch (25.4 mm - 38.1 mm) Excellent Good Good
Nitrogen Plasma Gage (0.5 mm) NR Good-Excellent Good-Excellent
and Air or CO2 Gage to 1/2 inch (0.5 mm - 12.7 mm) NR Good-Excellent Good-Excellent
Secondary 1/2 to 1-1/2 inch (12.7 mm - 38.1 NR Good-Excellent Good-Excellent
Ar/H2 Plasma and Gage to 1/4 inch (0.5 mm - 6.4 mm) NR NR NR
N2 or CO2 1/4 to 1-1/4 inch (6.4 mm - 31.8 mm) NR Good Excellent
Secondary 1/2 to 1-1/2 inch (12.7 mm - 38.1
)
NR Good Excellent
Kerf Width
Cut Surface
Bevel Angle
Top Edge
Rounding
Cut Surface
Drag Lines
Dross
Build-Up
Top
Spatter
A-00007
Figure 4-7 Cut Quality Characteristics
Cut quality will vary on different types of and material
thicknesses. The table shows the cut quality that can be
expected from this equipment for materials with a thick-
ness from gage to 1-1/2 inches (38.1 mm):
Description of Cut Characteristics
Excellent - Minimum bevel (0 - 4°), minimum kerf (2 x
tip orifice diameter), little or no dross, smooth
cut surface.
Good - Slight bevel (0 - 10°), slightly wider kerf (2-1/2 x
tip orifice diameter), some dross (easily re-
moved), medium-smooth cut surface, slight top
edge rounding.
Fair - Excessive bevel (over 10°), wide kerf (over 2-1/2 x
tip orifice diameter), medium to heavy dross,
rough cut surface, top edge rounding.
NOTES
Cut quality depends heavily on set-up and param-
eters such as torch standoff, alignment with the
workpiece, cutting speed, gas pressures, and op-
erator ability.