Advertisement
SECTION
6
MAINTENANCE
6-1.
ROUTINE MAINTENANCE
(Table 6-1)
a
WARNING: ELECTRIC SHOCK
can
kill;
HOT
SURFACES
can cause severe
burns.
Do
not
touch live electrical
parts.
Shut down
welding
power
source
and discon
nect
input
power before
working
on
torch.
Disconnect torch from
we/ding
power
source
before
inspecting, maintaining,
or
servicing.
Allow
a
cooling period
before
servicing.
Table 6-1. Maintenance
Schedule
Frequency*
Maintenance
Every
Week
Inspect
and clean
torch, cables,
and hoses
(see
Sections 6-IA thru
6-iC).
Check and
replace
torch
parts
or
weld cables
as
necessary
(see
Sections
6-lA thru
6-iC).
*Frequency
of service
is
based
on
units
operated
40 hours per
week. Increase
frequency
of maint
enance
if usage exceeds 40 hours per week.
A.
Inspection
And
Cleaning
a
WARNING:
Read and follow
safety
informa
tion at
beginning
of entire
Section
6-1
before
proceeding.
Inspect
torch for broken
areas,
cracks and loose
parts;
tighten, repair
and
replace
as
required.
Remove grease and dirt from
components,
and mois
ture
from electrical
parts
and cables.
B.
Torch
Body
a
WARNING:
Read and follow
safety
informa
tion at
beginning
of entire
Section
6-1
before
proceeding.
Once
a
week
inspect
condition of torch
body
compo
nents.
Replace
cup, heat
shield,
arid
0-ring
if
cracked. Main
tain
tight
fit of torch
components
to
ensure
good
weld
quality.
C.
Hoses, Connections,
And Cables
a
WARNING:
Read and follow
safety
informa
tion
at
beginning
of entire Section 6-1 before
proceeding.
Once
a
week
inspect
hoses and connections.
1.
Gas
Gas
leaks may result in poor weld
quality.
Inspect
hoses
for breaks.
Keep
connections clean and
tight.
2.
Power
Cable
Inspect
cables for breaks
in
insulation,
and
ensure
that
all connections
are
clean
and
tight. Repair
or
replace
cables if insulation breaks
are
present.
Clean and
tight
en
connections at each
inspection.
6-2.
TUNGSTEN
ELECTRODE
(Table
6-2
And
Figures
6-1 And
6-2)
Use Table 6-2
to
select the
correct
size and
type tung
sten
electrode.
Prepare
the
tungsten
electrode
using
the
following guidelines.
A
properly prepared tungsten
elec
trode
is essential
in
obtaining
a
satisfactory
weld.
A.
For
AC
or
DC
Electrode
Positive
Welding
(Figure
6-1)
Ball the end of
tungsten
electrodes
used for
ac or
dc
electrode
positive welding
before
beginning
the
welding
operation.
Weld amperage
causes
the
tungsten
elec
trode to form the
balled
end. The diameter of the end
should
not
exceed the diameter of the
tungsten
elec
trode
by
more
than
1-1/2
times. For
example,
the end
of
a
1/8
in.
(3.2 mm)
diameter
tungsten
electrode should
not
exceed
a
3/16
in.
(4.8 m)
diameter end.
Figure
6-1.
Properly Prepared Tungsten
Electrodes
B.
For DC Electrode
Negative
Welding (Figures
6-1
And
6-2)
a
CAUTION: HOT FLYING METAL PARTICLES
can
injure personnel,
start
fires,
and dam
age
equipment;
TUNGSTEN CONTAMINA
TION
can
lower weld
quality.
Shape
tungsten
electrode
only
on
grinder
with
proper
guards
in
a
safe location
wearing
proper
face, hand,
and
body
protection.
Do
not
use same
wheel for any other
job,
or
the
tungsten
will become contaminated.
Shape
tungsten
electrodes
on a
fine
grit,
hard
abrasive wheel used
only
for
tungsten shap
ing.
Grind
tungsten
electrodes
so
that
grind
ing
marks
run
lengthwise
with the electrode.
These
procedures
reduce the
possibility
of
the
tungsten
electrode
transferring foreign
matter
into the weld and
help
reduce
arc
wander.
~
I-4-1-1/2
Times
I
Electrode
~
Diameter
I.
>J.
AC And DC
Electrode Positive
A
]~_
2-1/2
Times
Electrode
Diameter
DC Electrode
Negative
S-0161
OM-1 558
Page
7
Advertisement
