operating at full rated flow shall not exceed 27 kPa 4 psi.
b.
Controls: Provide continuous supply of dry air by automatically
cycling operation of desiccant beds. Dryer shall be complete with
panel mounted gages showing pressure in each drying tower and
spark suppressor to protect microswitch in timer circuit. Total
c.
Filters: Provide prefilter upstream of dryer to remove oil vapor,
liquid water, and solid particles. It shall have greater than 99
percent efficiency in removing both 0.5 micron diameter solid
particles and 0.5 micron diameter oil aerosol. Filter shall have
indicate saturation with oil and which shall be mounted in a
transparent cast methyl methacrylate tube for visibility and
inspection while on stream. Protect transparent acrylic tube by a
safety shield. Provide afterfilter for removal of solid particles
down to 5 microns size.
][2.7.2.8
Refrigerated Air Dryer
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NOTE: Choose this subparagraph or the subparagraph
above, entitled "Desiccant Air Dryer."
**************************************************************************
Provide for systems not exposed to freezing temperatures a compressed air
dryer of the self contained refrigerated type complete with heat exchanger,
a commercial quality refrigeration system, a moisture separator and
condensate trap, and internal wiring and piping. Install dryer between
receiver and distribution line.
a.
aluminum granules of sufficient mass to ensure adequate cooling
capacity for varying air flow loads without causing excessive
heat exchanger with a sensing element located in the aluminum
granules, to shut down refrigeration system on low or no-load
conditions. Provide means to determine exchanger temperature.
b.
Moisture Separator: Provide a centrifuge type located within the
heat exchanger to provide for moisture separation at point of
minimum air temperature.
c.
Refrigeration Unit: Provide hermetically sealed type which
operates intermittently at all but maximum load conditions. Unit
shall be capable of drying [_____] standard L/s scfm of air to an
atmospheric dew point of not less than minus 23 degrees C 10
degrees F with entering air at 38 degrees C 100 degrees F,
kPa (gage) psig. House entire unit in a steel cabinet. Provide
cabinet with access door and panel for easy access to parts for
maintenance and inspection.
]2.7.3
Pressure Reducing Regulator
Provide self-operating type designed for not less than a 1724 kPa (gage)
minus 29 degrees C 20 degrees F to plus 65 degrees C 150 degrees F.
SECTION 15501N
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