Tweco PAK 10 - Manual (Page 27)

Manual No. 0-0515 15 Service
SERVICE
The Service Section is divided into six parts:
4.1 Torch Maintenance
4.2 Torch Leads and Leads Extension Packages
4.3 PAK Unit Maintenance
4.4 Gas Pressure Regulators
4.5 Trouble Shooting Guide
4.6 Test Procedures
4.1 TORCH MAINTENANCE
The 4B and 4BT torch parts are interchangeable with
two exceptions. First of all, the 4BT collet is a different
design than the 4B. This is so that the collet can be
installed from the front of the torch. By installing the
collet from the front of the torch the back cap is elimi-
nated in the 4BT design. These differences require
slightly different disassembly and assembly procedures.
When a different procedure is required, the torch model
will be specified, otherwise the step applies to both torch
models.
Torch Disassembly and Inspection
WARNING
Disconnect primary power before disassembling
the torch.
Disassemble the torch parts as follows:
1. Pull off the shield cup (1) and inspect it for damage.
Wipe it clean, or replace it if it appears to be dam-
aged.
2. Use the tip wrench (17) to unscrew the tip (2). Check
the tip for wear as indicated by an elongated or over-
size hole. Make sure that the tip is clean and that
threads have not been damaged. Replace the tip if
necessary.
3. Lift out the gas distributor (3). Remove the elec-
trode (7) and check the end for pitting.
1. Shield Cup
2. Tip
3. Gas Distributor
4. Liner (includes 9-2960 O-ring)
5. O-ring (included with Liner)
6. Sleeve
7. Electrode
8. O-ring (included with Shield Cup)
9. Gasket
10. Head Assembly:
a) PCH-4B
b) PCM-4BT
11. O-Ring: PCH-4B
12. Collet with 8-0525 O-Ring
13. Spring
14. Back Cap: PCH-4B
15. Liner Wrench
16. Tip Wrench
17. Collet Wrench: PCM-4BT
Figure 4-A Plasma Cutting Torch (PCH/M-4B), Exploded View
9 10b
3 9 5 4 1 2 6 7 8 10a
13
15
14 11
12
16 17
3 5 4 1 2 6 7 8
13 12
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