KEENAN MechFiber 250 and
280 Operator’s Manual
8
Revision C01, 04
th
Dec 2019
4. Operating principles
The KEENAN MechFiber mixer wagon
’s main operating functions are weighing,
chopping/mixing and feeding out.
4.1 Weighing
The KEENAN MechFiber mixer wagon
’s electronic weighing system allows the exact quantity
of individual materials to be loaded into the mixing chamber for accurate rationing. Individual
loads can be weighed, or successive loads accumulated to give total weight of feed. See
Section 6 (Weighing System) and the Readout Manual for more detailed information.
4.2 Chopping/mixing
Load ingredients in the sequence recommended by your KEENAN Physical Nutritionist, or as
suggested in Section 7 (Operation). Ensure bales are broken up prior to loading. As a general
rule, material should be tumbling freely when mixing. If not, then the machine is overloaded
and will not achieve the desired mix quality. Mixing is carried out by a centrally-mounted rotor
fitted with six angled paddles revolving at 5
–6rpm. Each paddle imparts a shearing action,
sweeping the feed ingredients onto the strategically placed knives to produce a consistent and
thorough mix with all types of materials, including baled silage, hay or straw, roots and liquids.
The angled paddles help mixing by sweeping the material from end to end. The placement of
the blades ensures the materials reach optimum size/length, without grinding it down and
destroying the all-
important ‘scratch factor’ of the forages, producing a MechFiber mix.
Mixing time will be determined by the required chop length. Follow procedures contained in
this manual or consult your KEENAN Physical Nutritionist for further information.
4.3 Feeding out
During mixing, the mixing chamber is separated from the feed-out chamber by a Variable Feed
Control (VFC) or guillotine door, thus ensuring complete mixing. The feed-out chamber
contains an auger which runs the entire length of the machine.
When chopping/mixing is complete, the feed-out tray should be set to the required position,
and the VFC-door dropped, allowing the material to be swept up by the paddles and pushed
onto the auger
– see figure 2. The VFC-door should be partially opened at first, and when feed
is seen discharging, then 15
–20 seconds should be allowed before opening the VFC-door fully.
Door position and ground speed should be set/used to allow an even feed-out rate.
CAUTION:
The VFC-door should only be opened or closed when the PTO is engaged
(paddles
turning) when material is in the machine.
