Cold Jet i3 MICROCLEAN Operator's Manual page 25

APPENDIX A:
BLAST AIR QUALITY
PORTABLE AIR
Portable air compressors are mainly used for shop tools, not dry ice blasting
units; therefore, they may not be equipped to cool or remove air moisture.
An after cooler and moisture trap/filter MUST be used. An after cooler with a
15 °F (-9 °C) approach is required to reduce the discharge air temperature 180 °F
(82 °C) to within 15 °F (-9 °C) of ambient air temperature.
If an air cooler is not used:
• Incoming air moisture will rapidly cool and freeze at the i
• Ice will accumulate in the feeder, distorting the air flow and seal.
• Ice will break off inside the hose and lodge in the nozzle, causing a jam.
• Ice may exit the nozzle and damage the target surface.
If blasting continuously, use an air dryer to further reduce the air moisture (dew
point). Desiccant dryers produce a dew point of -40 °F (-40 °C), resulting in a
dew point low enough for continuous blasting.
To verify the compressor is of adequate size for the i
air compressor needs to produce an air volume 10% greater than the i
MicroClean's maximum permissible air volume. To determine adequate air
volume, watch the pressure gauge while blasting
• If the gauge drops slowly, the compressor is insufficient.
• If the gauge drops quickly, there is a restriction or the pipe is too small.
• If the gauge stays steady, then the compressor and piping are adequate.
To maintain adequate pressure, the hose size from the compressor to the
i MicroClean needs to be a minimum 0.5in (13 mm) in diameter for lengths up
3
to 50 ft (15 m). Longer runs may require larger hose sizes.
MicroClean feeder.
3
MicroClean, the
3
3
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