MAGUIRE FLEXBUS Lite, Установка, эксплуатация и обслуживание

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Mix Problems
Customers with mix problems have several options available.
Decrease the batch size by lowering the FUL parameter value. This does two things. First,
it causes the components to be dispensed in smaller, more frequent batches, which places
more and smaller layers of material into the mix chamber. Second, it lowers the level of
material in the mix chamber immediately after a dispense. It is critical to proper mixing that
the mix blades reach up through the top of the material in the mix chamber during mix time.
Dispensing a large batch may bury these blades, particularly when the process is not
running at full blender capacity. A smaller batch size, while reducing throughput rate, will
help prevent the mix blades being covered during mix time.
Be sure level sensor is mounted in its lowest position, and increase sensitivity as much as
possible. Both serve to keep a batch from being dispensed so early as to cover the mix
blades.
On units without flow control valves (FCA), increase the DLY parameter to as number as
high as 50 percent of the time between cycles. DLY is the time delay (in milliseconds) from
the sensor being uncovered until we begin the batch. Increasing DLY allows the mix
chamber to empty somewhat before the next batch drops.
You may increase the mix time at the end of each batch by changing the last two digits of
the MIX parameter. If throughput is very high it may be better to run the mixer
continuously. However, added mix time sometimes causes separation after an initial
mixing. Different bulk densities and static electricity both aggravate this potential for
separation from excessive mixing.
If a blender is mounted on a stand over a surge hopper, there should be a FCA, automatic
flow control valve, fitted to the bottom of the blender. This valve must be plumbed so that it
is closed when the level sensor is uncovered. When the sensor is covered the valve opens
to release material. The purpose of this valve is to ensure mixing. The FCV parameter
delays the opening of this valve for 6 seconds. You can increase this delay time if you feel
additional mixing is required before release.
On model WSB-940, be sure the weigh bin has two baffles installed. These ensure
horizontal layering (as opposed to side by side layering) of materials prior to dropping into
the mix chamber.
Bulk density and pellet shape differences, specifically smooth virgin pellets mixed with
square higher density color pellets, can separate when dropped onto a sloping pile, as
exists in a hopper, Gaylord, or surge bin. The light round pellets flow like water to the
edges, while the heavier square color pellets stay put. This is difficult to correct. It is best
not to drop these kinds of blends into large containers.
Vacuum conveying can also separate materials of different bulk densities. Maintain high air
velocity to minimize this.
Models WSB-MB series units use an air drive for the mix blade, instead of an electric
motor.