sEctIoN 4
4.2.4. surface finish
process Induced roughness
Cut face is consistently rough. May or may not be confined to
one axis.
•
Incorrect Shield Gas mixture (See Process Data).
•
Worn or damaged consumables.
Machine Induced roughness
Can be difficult to distinguish from Process Induced Roughness.
Often confined to only one axis. Roughness is inconsistent.
•
Dirty rails, wheels and/or drive rack/pinion. (Re-
fer to Maintenance Section in machine operation
manual).
•
Carriage wheel adjustment.
4.2.5. Dross
Dross is a by-product of the cutting process. It is the undesirable ma-
terial that remains attached to the part. In most cases, dross can be
reduced or eliminated with proper torch and cutting parameter setup.
Refer to Process Data.
high speed Dross
Material weld or rollover on bottom surface along kerf. Difficult to re-
move. May require grinding or chipping. "S" shaped lag lines.
•
Standoff high (arc voltage)
•
Cutting speed fast
slow speed Dross
Forms as globules on bottom along kerf. Removes easily.
•
Cutting speed slow
Top View
Process
Induced
Roughness
150
opEratIoN
Cut Face
Machine
Induced
Roughness
or
Cut Face
Lag Lines
Rollover
Side View
Cut Face
Lag Lines
Globules
Side View