Tweco 100XL Plus CE PAK Master - Manuel (Page 31)

Manual 0-2813 4-5 OPERATION
H. Set Operating Pressure
Move the RUN/SET/LATCH switch to SET position. Ad-
just the gas pressure to 60 - 70 psi (4.1 - 4.8 bar). Refer to
Torch Manual for specific pressure settings.
I. RUN/SET Switch
Set the RUN/SET/LATCH switch to RUN position.
NOTE
Do Not use the LATCH position for automated
system applications.
The system is now ready for operation.
4.05 Cut Quality
Cut quality requirements differ depending on applica-
tion. For instance, nitride build-up and bevel angle may
be major factors when the surface will be welded after
cutting. Dross-free cutting is important when finish cut
quality is desired to avoid a secondary cleaning opera-
tion.
The following cut quality characteristics are illustrated
in Figure 4-6 below:
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 per-
pendicular 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.
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 spatter is dross
which accumulates on the top surface of the workpiece.
Excessive dross may require secondary clean-up opera-
tions 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.
Kerf Width
Cut Surface
Bevel Angle
Top Edge
Rounding
Cut Surface
Drag Lines
Dross
Build-Up
Top
Spatter
A-00007
Figure 4-6 Cut Quality Characteristics
Cut quality will vary on different types of and material thick-
nesses.
The following table shows the cut quality that can be expected
from this equipment for materials with a thickness from gage to
1 inch 25.4 mm))
T yp e o f M a t e r ia l
G a s
C ar b o n
S t ee l
S t a in le ss
S t ee l
A lu m in u m
A i r
G o od -
E x c e l l en t
G o od -
E x c e l l e n t
G oo d -
E x c e l l e n t
N i tr o g e n G o o d G o o d G o o d
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 removed), 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 sur-
face, top edge rounding.
NOTES
Cut quality depends heavily on set-up and pa-
rameters such as torch standoff, alignment with
the workpiece, cutting speed, gas pressures, and
operator ability.