Replacement Of Flex Support, Switch Band Or Handle; Replacement Of Torch Switch; Measuring Torch Gas Flows - ESAB PT-25 Manuel D'instruction

SECTION 5
5.6 REPLACEMENT OF FLEX SUPPORT, SWITCH
BAND OR HANDLE.
If damage to the flex support, switch band or torch handle
causes the need for replacement of any of these items, fol-
low the procedure in the section "Removal and Replacement
of the Torch Head" and replace the part(s) in question dur-
ing Step 7 prior to reattaching the torch head. This process
will be made easier by temporarily securing the sleeving to
the cables with vinyl electrical tape.

5.7 REPLACEMENT OF TORCH SWITCH

1. Follow Steps 1 through 3 of the section "Removal and
Replacement of the Torch Head".
2. Clip the black and white leads of the old switch as close
as possible to the red splice connections. Strip 1/4" of
insulation from the black and white leads.
3. Strip 1/4" of insulation from the new switch leads.
4. Attach the switch leads to the switch cable using the
two new splice connections included with the replace-
ment switch. Be sure to use a crimping tool made for
crimping this type of splice connection.
5. Reverse Steps 1 through 3 of the section "Removal and
Replacement of the Torch Head" to finish.

5.8 MEASURING TORCH GAS FLOWS

If low gas flow is suspected of causing poor cutting perfor-
mance or short consumable life, the flow can be checked
by using Plasma Torch Flow Measuring Kit - 0558000739
(19765). The kit includes a hand held rotameter (flowmeter)
which will indicate the gas flow rate exiting the torch. The kit
also includes a set of instructions which should be followed
exactly to insure safe and accurate use of the rotameter.
The PT-25's air or nitrogen flow rates should be as follows:
Cooling Flow ...........................................280 - 360cfh at 70 psig
Plasma Flow ............................................115 - 140 cfh at 70 psig
Total Flow ................................................395 - 500 cfh @ 70 psig
Measure the flow rates using a new 100 amp nozzle, a new
electrode and a new heat shield. Make sure that all parts
are properly installed and that the torch o-ring is in good
condition and not leaking. Measure the flows individually
if possible. If not possible, measure the total flow.
Low gas flow rates (lower than those given here) indicate
a restriction or a leak in the gas plumbing of the torch or
power source.
93
MAINTENANCE
(132 - 170 l/min. at 4.8 bar)
(54 - 66 l/min. at 4.8 bar)
(186 - 236 l/min. at 4.8 bar)