Tweco Thermal Arc TA 500 User Manual
Page 36
Service
4-2
Manual No 0-0470
For routine disassembly of the torch, no other parts need
to be removed. The electrode seat (4) does not require
replacement unless it has been damaged by a severe
electrode failure. This part unscrews from the center
post of the torch and should be gripped with a piece of
emery cloth. If necessary, pliers may be used very gen-
tly to remove this part.
Torch Assembly
CAUTION
There are several O-ring seals in this torch to
prevent leakage of the coolant. It is important to
observe the following precautions for all O-rings:
A. Make sure that the O-ring groove and the sur-
face that the O-ring will seal against are clean
and free of nicks and scratches.
B. Make sure that the O-ring is not cut or cracked.
C. Lubricate all O-rings with a light coating of Cat.
No. 8-4025 O-ring lubricant. This should be
used sparingly, just enough to make the O-ring
slippery but not enough to accumulate in the
torch.
If a new electrode seat (4) is installed in the torch, the
O-ring (3) in the center post of the torch should be re-
placed before installing the new one. The new elec-
trode seat may be gripped with emery cloth and
screwed into the center post of the torch. It is not nec-
essary to use pliers.
When assembling the torch, proper orientation of the
coolant baffle (20) relative to the M200 basic head as-
sembly (1) is important. The basic head assembly has
two projections on the sides of the plastic body that are
called ‘marks’ in step 8 below.
Assemble the torch as follows:
1. Install a new O-ring in the electrode seat. This
O-ring is included with each new electrode. The
O-ring is installed in the groove located about
3/8” (9.5 mm) back from the front of the elec-
trode seat.
2. Install the water tube (2) in the center of the
torch, small end first.
3. Install the electrode (5). Make sure it screws in
all the way.
4. Install new O-rings in the inner tip retainer (9).
These O-rings (7 and 8) are supplied with each
new cutting tip. The should be lubricated lightly
with Cat. No. 8-4025 O-ring lubricant and
placed in the proper groove in the tip retainer.
Figure 4-B M200 Torch
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