Cutting With Machine Or Automated Torch; Travel Speed; Piercing With Machine Or Automated Torch; Section 4 Torch: Operation - ESAB A120 Operating Manual

SECTION 4 TORCH:
OPERATION
4T.01 Machine and Automated Torch
Operation

Cutting With Machine or Automated Torch

These torches are activated by remote control pen-
dant or by a remote interface device such as CNC.
1. To start a cut at the plate edge, position the center
of the torch along the edge of the plate.

Travel Speed

Proper travel speed is indicated by the trail of the
arc which is seen below the plate. The arc can be
one of the following:
1. Straight Arc
A straight arc is perpendicular to the workpiece
surface. This arc is generally recommended
for the best cut using air plasma on stainless or
aluminum.
2. Leading Arc
The leading arc is directed in the same direction
as torch travel. A five degree leading arc is gen-
erally recommended for air plasma on mild steel.
3. Trailing Arc
The trailing arc is directed in the opposite direc-
tion as torch travel.
D i r
e c t
i o n
o f T
o r c
h T
r a v
e l
Straight Arc
A-02586
0-5430
Standoff Distance
Trailing Arc
Leading Arc
OPERATION
CUTMASTER A120
Automation and Machine Torch Operation
For optimum smooth surface quality, the travel speed
should be adjusted so that only the leading edge
of the arc column produces the cut. If the travel
speed is too slow, a rough cut will be produced as
the arc moves from side to side in search of metal
for transfer.
Travel speed also affects the bevel angle of a cut.
When cutting in a circle or around a corner, slowing
down the travel speed will result in a squarer cut.
The power source output should be reduced also.
Refer to the appropriate Control Module Operating
Manual for any Corner Slowdown adjustments that
may be required.

Piercing With Machine or Automated Torch

To pierce, the arc should be started with the torch
positioned as high as possible above the plate while
allowing the arc to transfer and pierce. This standoff
helps avoid having molten metal blow back onto the
front end of the torch.
When operating with a cutting machine, a pierce or
dwell time is required. Torch travel should not be
enabled until the arc penetrates the bottom of the
plate. As motion begins, torch standoff should be
reduced to the recommended 1/8 - 1/4 inch (3-6 mm)
distance for optimum speed and cut quality. Clean
spatter and scale from the shield cup and the tip as
soon as possible. Spraying or dipping the shield cup
in anti - spatter compound will minimize the amount
of scale which adheres to it.
4T.02 Automation Torch Parts Selection
Check the torch for proper consumable parts. The
parts supplied in the torch may not be correct for
the operator's chosen amperage level or operation
type. Use Deflector in mechanized applications that
do not require "Ohmic-Touch" initial height sensing.
Use Shield Cap and Ohmic Clip in mechanized ap-
plications that require "Ohmic-Touch" initial height
sensing. The torch parts must correspond with the
type of operation.
Torch parts:
Shield Cup, Cutting Tip, Electrode and Starter Cartridge
NOTE!
Refer to Sections 4T.08 and following
for additional information on torch parts.
Change the torch parts for a different operation as fol-
lows:
4T-1