Applications
The operational performance and maintenance requirements of a flowmeter application
are directly related to the care and consideration given to material flow patterns.
Material Feed
The following material in-feed characteristics are considered ideal:
•
material velocity is constant and relatively low
•
material flowrate is uniform (not pulsing)
•
air flow through the flowmeter is negligible
•
flowguide is always 1/6 to 1/2 full during operation
In cases where material cannot be gravity fed from an elevated bin to the flowmeter,
choose a mechanical feeding device that provides the most consistent material flow.
Most coal scale applications require an airlock on the flowmeter infeed and discharge; in
such cases, rotary airlock feeders can provide the airlock. Install a screw conveyor just
before the flowguide to modulate the heavily pulsing discharge of the infeed rotary
feeder. For best results, overfeed the screw conveyor, maintaining a constant plugged
screw condition.
screw conveyor
rotary airlock feeder
pneumatic supply
For high or variable velocity feeder material discharges, employ a
transition
s. (Refer to
For slight to moderate material pulsing at a frequency greater than one pulse per second,
use a heavier flowmeter sensing head range spring and/or viscous damper fluid as
compensation.
For heavily pulsing feeder discharges, at a frequency less than one pulse per second,
consult your local Siemens Milltronics representative,
or visit www.siemens-milltronics.com.
EN-4
rotary airlock feeder
C-40 coal scale
Feeder / Flowguide Transition,
Milltronics C-40 – INSTRUCTION MANUAL
reverse flowguide
page 5.)
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