plasma-cutting

1. Pacproc.ppt dah 2/26/97 1
PLASMA ARC
CUTTING

2. Pacproc.ppt dah 2/26/97 2
THREE CUTTING METHODS
MECHANICAL
Saw, Drill, Punch, Sheer
CHEMICAL
Oxy-Fuel
THERMAL
Plasma, Electron Beam, Laser

3. Pacproc.ppt dah 2/26/97 3
THERMAL SOURCE REQUIREMENTS
HIGH TEMPERATURE
HIGHLY FOCUSED and
INTENSE SOURCE
ADEQUATE MOMENTUM of
MEDIUM

4. Pacproc.ppt dah 2/26/97 4
TIG ARC
WELD PUDDLE
SHIELDING GAS
TUNGSTEN ELECTRODE
GAS CUP
OPEN ARC

5. Pacproc.ppt dah 2/26/97 5
TEMPERATURE DIFFERENCE

6. Pacproc.ppt dah 2/26/97 6
CONVENTIONAL TORCH

7. Pacproc.ppt dah 2/26/97 7
DUAL FLOW TORCH

8. Pacproc.ppt dah 2/26/97 8
WATER INJECTION TORCH

9. Pacproc.ppt dah 2/26/97 9
WATER INJECTION CUTS

10. Pacproc.ppt dah 2/26/97 10
OXYGEN AND AIR CUTTING
Best suited for carbon steel less than
one inch thick
Requires hafnium electrodes
Shorter electrode life
Limited to about 360 amps
Oxidizes cut face on non-ferrous material

11. Pacproc.ppt dah 2/26/97 11
Oxygen and AIR on CARBON STEEL
Very smooth cut face
Square edge on good side
Faster speeds than nitrogen at the same
current levels
Easier to remove dross if present
Reduced surface nitrides with oxygen

12. Pacproc.ppt dah 2/26/97 12
USE NITROGEN WHEN...
Cutting carbon steel over one inch thick
Cutting non-ferrous metals; Al & SS
Dross formation is not a problem
Surface nitrides are not a problem
There is a need to have longer
consumable life

13. Pacproc.ppt dah 2/26/97 13
USE OXYGEN WHEN...
Cutting carbon steel less than one inch
thick
There is a need to minimize dross
There is a need for a squarer cut face
There is a need to eliminate surface
nitrides for welding

14. Pacproc.ppt dah 2/26/97 14
PLASMA ARC
GOUGING

15. Pacproc.ppt dah 2/26/97 15
PLASMA GOUGING
PT-17AM IN AIR

16. Pacproc.ppt dah 2/26/97 16
PLASMA CUTTING vs GOUGING
PLASMA CUTTING
 TORCH HELD 90O TO PLATE
SURFACE
 HIGHLY CONSTRICTED ARC
 HIGH ARC FORCE
PRODUCES CUT
PLASMA GOUGING
 TORCH ANGLED 30O TO
PLATE SURFACE
 LARGER NOZZLE PRODUCES
SOFTER DEFUSED ARC
 ARC WASHES THE SURFACE
INSTEAD OF CUTTING

17. Pacproc.ppt dah 2/26/97 17
PLASMA GOUGING ADVANTAGES
Lower fume levels
Lower noise levels
High quality surface
Lower cost

18. Pacproc.ppt dah 2/26/97 18
PLASMA GOUGES
AL CS SS