When using roll compactors with
movable rolls, the actual gap size is resulting from the amount of powder
delivered to the gap and the amount of ribbon that is ejected from the gap.
This can be controlled by the speed of the augers that convey the powder
form the filling hopper to the gap.
Which is the right auger speed for the desired gap size?
This question is answered by Preset. The program computes the required
speed from various geometric values (as roll diameter, auger volume per revolution
etc.), machine settings (e.g. roll speed) and powder properties (density).
In addition to this, the actual throughput per hour, per 8h shift and per
day are prompted.
Although leading manufacturers equip their machines with automatic gap control
algorithms that will find the optimum settings on their own after some minutes,
it makes sense to set the values based on Preset's calculations beforehand:
Automatic gap control requires
some time (depending on the control parameters). Meanwhile ribbons of unwanted
thickness are produced. Especially in early development this waste of material
can not be afforded.
Of course, this could be
minimized by the use of high values for the control parameters which results
in quicker adaption, but this would mean that the machine is susceptible
to quick reactions even on unwanted events (such as plaques sticking to the
rolls). Therefore low values for the control parameters are favourable, but
this would result in longer response time which means waste of powder during
machine startup (see above).
With the right setting of
auger speed, the machine can be run with gentle (thus robust) gap control
and with minimal waste of powder.
System requirements
Windows 98SE or newer
approx. 1MB disk space
mb@jmbnet.de
