Dirt Or Contamination - ESAB PT-20AMX Manuel D'instruction

SECTION 5
WARNING
!
Before any maintenance is at-
tempted on this torch, make
sure the POWER SWITCH on the
console is in the OFF position
and the PRIMARY INPUT POWER
is DEENERGIZED.
NOTE:
Part numbers in parenthesis ap-
ply to "CE" / European units only.
5.0 General
1. The gas flow check valve is part of the safety interlock and is permanently assembled
in the torch head. The head must be replaced if this valve malfunctions.
2. Periodically check heat shield, electrode holder assembly and electrode insulator.
Replace if worn or damaged.
3. Apply a thin film of lubricant 17672 (0558000443), supplied in spare parts kit, to
o-ring. Check o-ring for damage whenever shield is removed. Replace if necessary.
4. Power and pilot arc cables should be inspected periodically. If cuts through
protective sheath or if gas leaks are noted, replace damaged component.
5.1

Dirt or Contamination

Dirt or other contamination in the torch and loose consumable parts can cause
premature failure of the PT-20AMX / PT-21AMX Torch through internal arcing. To
avoid this, users are instructed to do the following:
1. Ensure that clean, dry, or oil-free air is being used.
2. Avoid excessive use of the silicone o-ring grease used to lubricate the torch o-
ring. A thin film is sufficient.
Wipe the torch body insulator clean with a cloth before 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.
5.2 Loose Consumables
Tests have shown that with proper use of the torch within rated operating conditions
(especially arc current and gas flow rate), the torch consumable parts do not become
loose if they are firmly installed in the first place.
1. Tighten heat shield fully at each consumable change or inspection. "Fully" means
at least 5mm (0.20") of rotation after electrode seat contacts electrode holder.
2. Check consumable tightness at beginning of each work shift, even if everything
was working normally at the end of the previous shift.
Ensure that the torch electrode seat and electrode holder are clean and free of dust
or dirt. Debris may prevent mating surfaces from having solid contact.
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MAINTENANCE