AEC Continuous Vacuum/Pressure Conveying Systems - Manual (Page 63)

Page 62 Single- and Dual-Blower Continuous Vacuum/Pressure Systems
Dry Flow Chem Car (GATX)
Attach the adapter assembly to the A style nozzle cap.
Material Pickup Device Operation and Settings
Making Railcar Unloading Connections
All Style Cars
All probe connection settings and operations follow the same pattern, no matter which type of
railcar is being unloaded.
1. Loosen the locking thumb screw on the adapter assembly and move 45° in either
direction from the 0° position. Hand-tighten the adapter thumb screw to lock the setting.
With the tubing connections made as specified, start up the power unit.
The most efficient operation during conveying usually is obtained at vacuum gauge
readings of 10 inches of mercury. The 45° setting of the car connection will, in most
cases, have to be increased to reach this reading.
The bulk density of the material, distances of conveying, number of material tube bends,
and the outside air temperatures in extreme climate conditions, will all dictate the proper
settings for most efficient operation.
2. If surging occurs, which momentarily increases vacuum to a point in excess of the high
level vacuum switch setting at the power unit, the system shuts off before a full vacuum
hopper of material is drawn.
To correct this, decrease the adapter adjustment reading by about five (5) inches of
mercury (169.5 millibars) and recycle the power unit. Do not hurry this adjustment.
Cycle the power unit at least twice to bring the system into equilibrium before making
further adjustments.
3. Usually, when the probe connection is set for your system and type of material, no further
adjustments are necessary. Adjustments to the system are simple if you change material
type.