53
Donaldson Company, Inc.
Start-Up/Shut-Down Sequences
The recommended sequences for motor start-up and shut-
down are outlined below. These sequences assure minimal
material build-up in the hopper of the collector.
Not following these sequences
can adversely impact the life of the
filters and may result in equipment damage.
Start-Up Sequence
1. Pneumatic conveyor or transfer blower, if equipped.
2. Rotary airlock and screw conveyor - start simultaneously.
3. Manifold drive and pulse timer.
4. Positive-displacement cleaning blower.
5. Main blower.
Shut-Down Sequence
1. Main blower.
2. Positive-displacement cleaning blower.
3. Manifold drive and pulse timer.
4. Rotary airlock and screw conveyor - shut-down
simultaneously.
5. Pneumatic conveyor or transfer blower, if equipped.
Operation
Start-Up
1. Start the positive-displacement cleaning blower and check
for proper blower rotation.
2. Turn power to timer and solenoid ON.
3. Check solenoid and diaphragm valve operation.
4. Adjust the timer to allow the cleaning system pressure to
rise to 8-9 psig between pulses. Too short of an OFF time
results in inadequate cleaning pressure; too long of an
OFF time will result in the pressure relief valve discharging
cleaning air.
5. Close the isolation petcock between the positive-
displacement blower and the gauge.
6. Start the system as shown in Start-Up Sequence.
7. Adjust fan for proper airflow with the volume control
damper, if equipped.
8. Measure initial pressure drop across the tube sheet and
filter bags during normal process operation with dust
actively generated. Pressure drop will gradually rise until
an equilibrium pressure drop is achieved, generally 3 to 4
“wg for seasoned filters, although anything between 1 to 6
“wg is considered normal.
