AAF International OptiFlo Cartridge Collector - Manual (Page 6)

6
9.0 On-line Cleaning
1. A timer continuously and progressively energizes the solenoid on
each valve (attached to the compressed air reservoir) releasing a
sharp burst of compressed air to a pulse pipe in line with a
cartridge or column of cartridges. On special applications using
the demand pulse option, the timer operation can be activated (or
deactivated) at high (or low) pressure drop settings.
2. This sharp burst of compressed air into the pulse pipe results in
a shock wave traveling upstream through the center of the
cartridge(s).
3. The shock wave and additionally induced clean air from the
outlet plenum momentarily reverse airflow and dislodge
accumulated dust from the filter cartridge(s).
4. The configuration allows discharged dust to fall freely into the
hopper below. Additionally, the downward path of the incoming
air will blow the dislodged dust toward the hopper.
10.0 Initial Start-Up Instructions
1. Check the compressed air lines to be sure they are connected to
the NPT connection on the compressed air manifold(s). Turn on
the compressed air supply to the manifold(s). Pressure should be
90-100 psig.
2. Check that cartridges are properly installed. Close the access
ports and secure tightly.
3. Be sure the hopper discharge device is operating properly.
Follow manufacturer’s instructions.
4. Energize the solid-state pulse panel. The “On” light inside the
enclosure will illuminate. With the demand pulse option, decrease
the pressure switch set points to “zero” to activate timer.
5. Listen for firing of the pilot solenoids and diaphragm pulse valves
to determine that they are operational. Note that as each
solenoid is activated, a small puff of air vents from the hole at the
solenoid valve base.
6. Partially open the fan damper or duct blast gates.
7. Start fan and note the initial differential pressure gauge reading.
This gauge reading indicates the pressure drop across the filter
face and eventually the dust cake. Rising pressure readings
indicate that dust is being collected.
WARNING: Efficient fan sizing includes an allowance for pressure
drop across filter media with a thin residual dust cake as the normal
operating condition. During the initial dust caking period for New
media, unit airflow may have to be restricted to avoid fan motor
overload. Partial blank-off of the inlet or outlet will do. Fan motor
amperage readings will indicate need and adequacy.
Do not operate fan for extended periods without imposing the
pressure drop induced by conditioned media or checking fan
motor amperage.
NOTE: With a light dust load, pressure drop may take days to change
appreciably.
8. The final operating pressure drop reading should be in the range
for 2 to 4 inches w.g. Cleaning pulses will cause momentary
spikes in the pressure reading. In making adjustments to the
factory settings, remember the following:
• Increasing the time interval between pulses will increase the
pressure drop.
• Decreasing the time interval will tend to lower the
pressure drop.
• Excessive pulsing can cause premature cartridge wear and
adversely affect overall filtration efficiency.
With the demand pulse option adjust only the pressure settings.
Never adjust the pulse duration (“on time”) without first
consulting your AAF representative.
10.1 Maintenance
1. Daily or Weekly — Record the collector pressure drop for at
least the first 30 days of operation. Adverse operating conditions
can be detected by a change in pressure drop. After start-up, the
pressure drop will gradually rise to its normal operating level,
which will generally be less than 4.0" w.g.
2. Monthly — Open the air reservoir drain plugs to expel
condensation. Check the compressed air line regulator, dryer,
and filter for proper operation. Also inspect the hopper outlet
discharge device(s) for proper operation and air seal.
Follow manufacturer’s instructions for inspection and
maintenance.
3. Six Months — Ducts leading to and from the collector should be
inspected for dust build-up at least once every six months. In
addition, perform the following inspections:
a. Examine the filter cartridges. Look for signs of excessive
wear or damage on the cartridges.
b. Inspect joints for evidence of air or dust leakage.
c. Check for evidence of moisture or dust buildup within
the collector.
d. Check all electrical apparatus for proper operation.
e. Check to see if the diaphragm pulse valves and solenoid
valves are pulsing when energized by the timer.
f. Check discharge air condition for signs of dust.
4. Filter Cartridge Replacement — Follow the procedures in the
sections for Filter Cartridge Installation and Initial Start-Up
Instructions.