Hypertherm Freedom 38 PPA, Руководство по обслуживанию

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158 Freedom 38 PPA Service Manual 809010
6 – Air Compression Components
 Replace the air pressure gauge on page 171
 Replace the unloader valve on page 172
 Replace the muffler and orifice adapter on page 174
 Replace the separation tank on page 175
 Replace the separation tank manifold on page 178
 Replace the cooler unit on page 181
 Replace the compressor cooling fan on page 183
 Replace the pressure relief valve on the separation tank on page 185
 Replace the oil level gauge on page 186
 Replace the air drying filter assembly on page 187
 Replace the pressure relief valve on the air drying filter assembly on page 190
 Replace the ball valve, elbow fitting, and elbow coupler on the separation tank on page 191
 Replace the condensate release lever on page 193
The air compression components are identified in Figure 82 . A rotary screw compressor with oil injection is belt-driven by
the engine and supplies the compressed air for the plasma power supply and the auxiliary compressed air port at the front
panel.
The compressed air and oil output are separated by the oil separation tank and then the oil separation filter. The air is
cooled by the air cooler and stored in the air tank. An air drying filter removes moisture from the compressed air, which is
then available for the plasma supply and auxiliary air port. The pressure level can be read from the front panel air pressure
gauge. Air pressure is maintained by the pilot unloader valve. When the pressure exceeds the maximum level the pilot
unloader valve vents excess pressure through the muffler. This maintains the pressure within desired levels. The orifice
adapter in the pilot unloader valve maintains enough pressure in the system when venting to allow oil to flow back to the
compressor through the oil mist line. The pilot unloader valve has been specially calibrated for the system and must not
be adjusted.
A temperature switch monitors the compressor for overheating. A thermostatic valve allows the oil to be circulated
through the oil cooling unit when it reaches temperature. The majority of the oil in the separation tank falls to the bottom
and is cooled and returned to the compressor head. Some oil filtered out by the separation filter is returned to the
compressor intake through the mist line. The scavenge orifice, located at the junction of the inlet valve and mist line,
controls the rate of oil drawn from the separation filter. If the orifice becomes clogged the system cannot remove oil mist
from the compressed air. If the orifice is missing the system will not build up pressure correctly.
Condensate is removed by valves that are located on the oil separation tank and at the front panel for the air tank. A relief
valve is located on the separation tank manifold to release pressure within the separation tank. A safety relief valve on the
air drying filter manifold releases air pressure in the system should the pressure exceed 175 psi. All pressure should be
released from the system from the condensate relief valve whenever servicing the unit. Pressure in the separation tank
manifold should be released by the valve on the separation tank manifold prior to servicing any air compression lines or
hoses.