Tweco 20mm Cutmaster - Manual (Page 60)

CUTMASTER 20mm
SERVICE 5T-2 Manual 0-5078
5T.02 Inspection and Replacement
of Consumable Torch Parts
WARNING
Disconnect primary power to the system be-
fore disassembling the torch or torch leads.
DO NOT touch any internal torch parts while
the AC indicator light of the Power Supply is
ON.
Remove the consumable torch parts as follows:
NOTE
The shield cup holds the tip and starter car-
tridge in place. Position the torch with the
shield cup facing upward to prevent these
parts from falling out when the cup is removed.
1. Unscrew and remove the shield cup from the
torch.
NOTE
Slag built up on the shield cup that cannot be
removed may effect the performance of the
system.
2. Inspect the cup for damage. Wipe it clean or
replace if damaged.
Art # A-08067
Shield Cups
3. On torches with a shield cup body and a shield
cap or deflector, ensure that the cap or deflector
is threaded snugly against the shield cup body.
In shielded drag cutting operations (only), there
may be an O-ring between the shield cup body
and drag shield cap. Do not lubricate the O-ring.
Drag Shield Cap
Shield
Cup Body
O-Ring No. 8-3488
Art # A-03878
4. Remove the tip. Check for excessive wear (indi-
cated by an elongated or oversized orifice). Clean
or replace the tip if necessary.
Good Tip Worn Tip
A-03406
Example of Tip Wear
5. Remove the starter cartridge. Check for excessive
wear, plugged gas holes, or discoloration. Check
the lower end fitting for free motion. Replace if
necessary.
Art # A-08064_AC
Spring-Loaded
Lower End Fitting
Full Compression
Spring-Loaded
Lower End Fitting at Reset /
Full Extension
6. Pull the Electrode straight out of the Torch Head.
Check the face of the electrode for excessive wear.
Refer to the following figure.
Worn Electrode
New Electrode
Art # A-03284
Electrode Wear
7 . Reinstall the Electrode by pushing it straight into
the torch head until it clicks.
8 . Reinstall the desired starter cartridge and tip into
the torch head.
9. Hand tighten the shield cup until it is seated on
the torch head. If resistance is felt when installing
the cup, check the threads before proceeding.
This completes the parts replacement procedures.