Tweco 300 Maximizer - Manual (Page 31)

Manual 0-2554 5-1 SERVICE
SECTION 5:
SERVICE
5.01 Introduction
This Section describes basic maintenance procedures per-
formable by operating personnel. No other adjustments
or repairs are to be attempted by other than properly
trained personnel.
WARNINGS
Disconnect primary power at the source before dis-
assembling the torch or torch leads.
Frequently review the Important Safety Precau-
tions in Section 1 of this Manual. Be sure the op-
erator is equipped with proper gloves, clothing, eye
and ear protection. Make sure no part of the
operator’s body comes into contact with the work-
piece while the torch is activated.
Sparks from the cutting process can cause damage
to coated, painted, and other surfaces such as glass,
plastic and metal.
Handle torch leads with care and protect them from
damage.
5.02 General Torch Maintenance
A. Cleaning Torch
Even if precautions are taken to use only clean air
with a torch, eventually the inside of the torch be-
comes coated with residue. This buildup can affect
the pilot arc initiation and the overall cut quality of
the torch.
WARNINGS
Disconnect primary power to the system before
disassembling the torch or torch leads.
DO NOT touch any internal torch parts while the
AC indicator light on the front panel of the power
supply is ON.
The inside of the torch should be cleaned with elec-
trical contact cleaner using a cotton swab or soft wet
rag. In severe cases, the torch can be removed from
the leads (refer to Section 5.06, Servicing Machine
Torch Components) and cleaned more thoroughly by
pouring electrical contact cleaner into the torch and
blowing it through with compressed air.
CAUTION
Dry the torch thoroughly before reinstalling.
B. Checking Center Insulator
The center insulator separates the negative and posi-
tive sections of the torch. If the center insulator does
not provide adequate resistance, current which is in-
tended for the pilot arc may be dissipated into the
torch head, resulting in torch failure.
WARNINGS
Disconnect primary power to the system before
disassembling the torch or torch leads.
DO NOT touch any internal torch parts while the
AC indicator light on the front panel of the power
supply is ON.
1. Remove the shield cup body, end cap, tip, gas dis-
tributor, and electrode from the torch. Disconnect
the torch leads from the system to isolate the torch
from power supply circuits.
2. Using an ohmmeter (set to 10K or higher), check
for continuity between the positive and negative
torch quick disconnect fittings. Infinite resistance
(no continuity) should be found. If continuity is
found, refer to Section 5.07, Torch and Leads
Troubleshooting.
C. Torch O-ring Lubrication
The internal o-rings on the torch head assembly (elec-
trode, gas distributor and tip) require lubricating on
a scheduled basis. This will allow the o-rings to re-
main pliable and provide a proper seal. The o-rings
will dry out, becoming hard and cracked, if the o-
ring lubricant is not used on a regular basis. This can
lead to potential leaks internally and externally. Fail-
ure of o-rings that seal against outside “air” entering
the torch assembly can cause severe contamination.
These contaminants can destroy or shorten the parts
life of tips, electrodes, and internal torch parts.
It is recommended to apply a very light film of o-
ring lubricant, Catalog Number 8-4025, to the inter-
nal torch head assembly o-rings on a weekly basis.