73
SECTION 6 TROUBLESHOOTING
Problem Possible Cause Corrective Action
Reduced Electrode Life 1) Diving
2) Work ipping
3) Catching on piece
4) Excessive speed
5) Excessive pilot arc on time
6) Process factors
7) Inadequate initial delay. Pierce not com-
plete before starting
1). Diving is usually caused by a change
in arc voltage when an automatic
height control is in use. Diving can
result in damage to the nozzle. Usu-
ally, the voltage change is the result
of a change of direction or speed to
negotiate a corner, failure to disable
the height control during piercing,
or of plate falling away from the arc.
These problems can be dealt with by
disabling the height control in such
situations and by extinguishing the
arc earlier when nishing the cut on
falling plate.
Diving may also be caused by a
problem with the height control or
signals fed to it.
2). The nozzle may sometimes be dam-
aged if the torch hits a ipped up
part. This is dicult to avoid entirely
but careful part programming can
minimize the problem.
3). This refers to crashes or nozzle dam-
age caused by the front end of the
torch catching on top spatter after
a pierce. Hold the torch at a higher
stando for a longer lead-in to avoid
this problem.
4). Reduce speed to prevent rooster
tailing during cut. Reduce speed on
corners if rooster tailing occurs only
when coming out of corners.
5). Check the following:
a). When the torch is properly posi-
tioned, it should start on the rst
pop.
b). The pilot arc contactor should
open as soon as the arc trans-
fers.
c). Pilot Arc switch in wrong posi-
tion.
d). Gas or water leak in torch.
6). Same as for electrode.
7). Increase delay time.
To Next Page
Loading...
