Tweco Pak 200 - Manual (Page 81)

Manual 0-5057 7-1 TORCH MAINTENANCE
TORCH MAINTENANCE PAK 200
7.01 Introduction
This section describes basic maintenance procedures
performable by operating personnel. No other adjust-
ments or repairs are to be attempted by other than properly
personnel.
!
WARNING
Disconnect primary power at the source before
disassembling the torch or torch leads.
Frequently review the "1.02 Important Safety
Precautions" on page 1-1. Be sure the
operator is equipped with proper gloves,
clothing, eye and ear protection. Make sure no
part of the operator’s body comes into contact
with the workpiece 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.
7.02 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 becomes
coated with residue. This buildup can affect the pilot
arc initiation and the overall cut quality of the torch.
WARNING
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 electrical
contact cleaner using a cotton swab or soft wet rag. In
severe cases, the torch can be removed from the leads
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
intended for the pilot arc may be dissipated into the
Torch Head, resulting in torch failure.
WARNING
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, tip, gas distributor, and
electrode from the torch. Disconnect the torch
leads from the power supply 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 fi ttings. Infi nite resistance (no continuity)
should be found. If continuity is found, refer to
"7.08 Torch
And Leads Troubleshooting" on
page 7-8.
C. Torch O-ring Lubrication
The internal o-rings on the Torch Head assembly
(electrode, gas distributor and tip) require lubrication
on a scheduled basis. This will allow the o-rings to
remain 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. Failure 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 fi lm of o-ring
lubricant, (Catalog Number 8-4025), to the internal
Torch Head assembly o-rings on a weekly basis.
SECTION 7:
TORCH MAINTENANCE