ESAB PT-26 Manual De Instrucciones página 17

SECTION 4
4.1 DISASSEMBLY OF FRONT END
Make sure power switch on power source is in the
OFF position and primary input power is
deenergized.
If the stand-off guide is being used, remove it by twisting
clockwise and pulling it from the heat shield.
Unscrew the heat shield and remove it from the torch.
The nozzle should remain in the torch head. Some cool-
ant leakage is normal as the shield is removed. Inspect
the heat shield. There should be no signs of arcing any-
where inside the shield. The outer insulating jacket
should not be severely worn or charred. Replace the
shield if any of the above mentioned damage is found.
Pull the nozzle from the torch head and inspect it. The
orifice should be round at both the entrance and the exit.
Replace the nozzle if the orifice is oval shaped or dam-
aged. The nozzle may have grey to black deposits on
the inside surfaces. They may be cleaned with steel
wool but care must be taken to remove all traces of the
steel wool afterward.
Inspect the electrode. If it has a pit more than 0.062"
(1.59mm) deep at its center, replace it.
Each time the electrode is replaced, one should inspect
the electrode holder. There should be no signs of arc-
ing and the o-rings should not be worn or damaged.
Inspect the insulator. If any signs of arcing are found,
replace it.
Inspect the torch head o-rings. If they are worn or dam-
aged, replace them. They will last longer if they are kept
covered with a thin film of silicone lubricant
(0558000443). Use just enough to make the o-ring
appear wet or shiny but do not leave clumps of excess
lubricant.
After all of the front end parts have been inspected and
replaced as needed, reassemble the torch as described
in the section "Assembling Front End Parts".
4.2 GENERAL
Periodically check the heat shield, electrode holder as-
sembly and insulator. If any of these parts are damaged
or excessively worn, replace them.
Check the torch o-rings daily. If any o-ring has nicks,
cuts or other damage, replace it. If it is dry, lubricate it
with a thin film of lubricant, P/N 0558000443. If no drag,
caused by the o-ring, is felt when installing the heat
shield, replace the o-ring.
The torch cable sleeving should be inspected periodi-
cally. If any damage to the sleeving is found, inspect the
torch power and pilot arc cables for damage. If gas leaks
or damage of any kind are found, replace the compo-
nents in question.
4.3 DIRT OR CONTAMINATION
Dirt or other contamination can cause premature failure
of the PT-26 torch through internal arcing. To avoid this,
users are instructed to do the following:
1. Insure that clean, dry, oil-free air is used for plasma
and/or shield gas.
2. Avoid excessive use of the silicone o-ring grease
on the torch o-rings. A thin film is sufficient.
3. Wipe the torch body insulator clean with a cloth be-
fore installing each fresh set of consumables. The
ability of the insulator to resist arc tracking over its
surface is reduced when dirt or other contamination
is allowed to collect there.
4. When the torch is not in use, store it with a full set of
front end parts installed. This will prevent dirt from
collecting in the torch and will help protect the torch
head in case it is accidentally dropped.
4.4 REMOVAL AND REPLACEMENT OF THE TORCH
HEAD
Note the position of all components and tape locations
before performing disassembly to ensure proper posi-
tioning of components and tape during reassembly. Re-
fer to Figure 5.1.
1. Slide the flex support rearward, onto the cable
sleeving until it is approximately 18" (457.2mm) to
the rear of the handle.
2. Remove the tape near the end of the torch handle.
3. Slide the switch band and switch rearward and off
the handle.
4. Slide the cable sleeving rearward.
5. Twist and pull the handle from the torch head and
slide it rearward to expose the torch cable connec-
tions.
6. Using two wrenches at each connection, unthread
the two torch connections. The wrench sizes re-
quired are 0.38" (9.5mm) and 0.44" (11.1mm).
241
MAINTENANCE