Tweco 51 with SL100SV CutMaster - Manual (Page 50)

OPERATION 4-8 Manual 0-4640
4
4.04 Cut Quality
NOTES
Cut quality depends heavily on setup and parameters such as torch standoff, alignment with the workpiece, cutting
speed, gas pressures, and operator ability.
Cut quality requirements differ depending on application. 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 operation. The following cut quality characteristics are illustrated in the following figure:
Kerf Width
Cut Surface
Bevel Angle
Top Edge
Rounding
Cut Surface
Drag Lines
Dross
Build-Up
Top
Spatter
A-00007
Cut Quality Characteristics
A. Cut Surface
The desired or specified condition (smooth or rough) of the face of the cut.
B. Nitride Build - Up
Nitride deposits can be left on the surface of the cut when nitrogen is present in the plasma gas stream. These buildups may
create difficulties if the material is to be welded after the cutting process.
C. 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.
D. 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.
E. 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.
F. Kerf Width
The width of the cut (or the width of material removed during the cut).
G. 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.