seCTIoN 4
4.1
GeNeRAL
WARNING
4.2
INsPeCTIoN AND CLeANING of CoNsUMABLes
A. Disassemble the front end of the PT-7 as follows:
1. Position torch head in a downward direction (refer to Figure -1) and remove the shield. The nozzle, swirl
baffle, and electrode will drop from the head and remain in the shield. Remove these components and
inspect for wear. The nozzle and electrode will generally wear at the same rate. For best performance,
replace together.
. Nozzle: Replace if the orifice is clogged, nicked, or out-of-round.
. Electrode: See Figure 4-1 for electrode maintenance.
4. Shield: The face of the shield will gradually erode from the heat and molten metal spray. Replace the
shield if more than 1/8 inch (. mm) has eroded from the face. Refer to Figure 4-1.
5. Swirl Baffle: This is a ceramic part and may crack or chip if dropped. Always replace if cracks or chips are
present.
6. O-ring: Lubricate as per Figure 4-1. Replace if cut or worn. Air leaking past this seal will reduce cutting
performance.
B. To replace the above front end components, refer to Figure -1.
THE HEAT SHIELD FACE WILL GRADUAL-
LY ERODE WITH USE. SEE PARAGRAPH
4..A.4.
BefoRe ANY MAINTeNANCe Is ATTeMPTeD oN ThIs ToRCh, MAKe
sURe The PoWeR sWITCh oN The CoNsoLe Is IN The "off" PosI-
TIoN AND The PRIMARY INPUT Is DeeNeRGIZeD.
LUBRICANT (P/N 1767) CAN BE APPLIED TO
O-RING OR HEAT SHIELD.
HEAT SHIELD
19/"
(15.1 mm)
figure 4-1. o-ring, electrode, and shield Maintenance
O-RING
REPLACE ELECTRODE BEFORE LENGTH
BECOMES SHORTER THAN 19/ INCH -
(15.1 mm).
ELECTRODE
MAINTeNANCe