Prepare for the feeding season with a 6-step TMR mixer maintenance program

Published on Thu, 09/29/2016 - 1:11pm

Dr. Alan S. Vaage PhD.

For many beef producers feeding is a seasonal affair that often begins in the fall when grazing is no longer available.  Now is the time, before feeding must begin, to bring your TMR mixer out of storage and address a number of maintenance items to ensure a smooth feeding season.

  1. Wash the mixer, especially the inside:  Ideally the mixer will have been cleaned of any feed residues before being put away at the end of the last feeding season.  Regardless, clean the mixer again to ensure residues and accompanying spoilage and toxins that have accumulated during storage are not feed out in the first batch of feed.  More importantly, pay special attention to remove any residues sticking to the walls of the mixer, as these can impair feed sliding down the sides of the mixer and create dead-spots.  This is especially the case when feeding liquids such as whey, molasses or corn steep liquor.
  2. Detach and inspect under vertical augers:  Most vertical auger machines have at least one oil line that rises from the floor of the mixer between the wall of the auger and the planetary gearbox to maintain the level of the oil in the gearbox.  As the mixer is used, feed material and moisture may enter and accumulate in this space, and under the right conditions, damage the oil tube, cause unnoticed loss of oil, and subsequently cause damage in the planetary gearbox.  Most manufacturers of vertical mixers therefore state the auger(s) should be lifted and the area underneath cleaned and inspected periodically to prevent such a malfunction.  Increasingly hard initial starting of the TMR mixer during freezing weather may be an indication of accumulation of moist material between the auger and the planetary gearbox.
  3. Inspect the auger:
    1. Knives:  If bales or other long forage are to be processed, ensure knives are sharp enough to do the job. Generally, it is the upper half of the knives that break bales apart, while the lower half do about eighty percent of the actual cutting and particle size reduction.  Knives are not sharp if you can run your fingers along the outer third of the blade without fear of being cut; if they can’t cut you, they cannot cut forage.  It is often sufficient to replace the lower knives and rotate the replaced knives to the upper positions.  Often, blade edges are dulled by being rounded over by excessive amounts of stones and dirt in forage.  Efforts to reduce this, such as being more careful where bales or stored or digging into dirt floors of bunker silos, will increase the working life of knives.
    2. Angling blade:  Many vertical augers have an angling blade or “kicker-plate” on the outer leading edge of the auger.  This is an essential part that helps “load” the feed into the auger, and it wears down over time.  Generally, mixing time and the risk of dead-spots increase as the angling blade wears.  It should be replaced when mixing efficiency is sufficiently impaired, usually before the angling blade is half worn.
    3. Planetary gearbox bolts:  The act of mixing, and force of the feed on the auger, places a tremendous force on the bolts and floor securing the planetary gearbox and auger in place.  The bolts should be inspected and retorqued to ensure they remain tight.
    4. Grease planetary top bearing:  The top bearing of the planetary gearbox takes a large proportion of the force placed on the gearbox.  Ensure that this bearing is greased now, as well as at appropriate intervals, and that it is taking the grease, to ensure the bearing does not fail from lack of lubrication.
  4. General lubrication:  Conduct annual lubrication requirements. Apart from greasing all available fittings, this may include scheduled fluid changes recommended by the manufacturer, such as for the planetary gearbox(es) and hydraulic components.
  5. Inspect and test scale system:  The scale system is arguably the most important subsystem on the TMR mixer today in that its accurate operation is essential to ensure cost-effective feeding of TMR rations.  These systems, however, are subject to damage and drift, and should be tested periodically to ensure optimal operation, as follows:
    1. Weigh someone on an accurate bathroom or other reference scale, and then repeatedly while positioned above each weigh-bar on the TMR mixer.  Ideally, the weight recorded over each weigh-bar should not deviate by more than 10% from the average.  If one or more weight deviates appreciably, check to see that there is no obstruction around, nor damage to, the mounts of the affected weigh-bars.  If there is, repairs may need to be conducted by a qualified TMR mixer mechanic. Alternatively, the weigh-bar may have become faulty and may need to be replaced.
    2. Assuming no concern with an individual weigh-bar, the average weight of the person on the mixer scale system should be close to the weight given by the reference scale. If it is out by less than 10%, the mixer scale indicator can be calibrated to bring the indicated weight closer to the reference weight.  If there is a substantial difference between the mixer weight and a known weight (>10%), it would be wise to have the scale system inspected by a qualified mechanic.
  6. Inspect tires, road signs and lights:  Finally, depending on where the mixer is to be used, be sure to check that it is appropriately equipped for road safety and to be operated on public road. This may include ensuring that any installed road lights are actually working.  Finally, check the tires for wear, and inflate them to the recommended pressure to minimize the chance of tire failure under load, and you’re set to go.

With the above preparations you should be ready for a smooth feeding season, and left to focus on what really matters, cost-effective, healthy, and hopefully, profitable production ...“Because Nutrition Matters™”.
Dr. Alan Vaage is a Ruminant Nutritionist with over 30 years of experience in the beef industry, and currently provides technical support for Jaylor Fabricating Inc., Orton, Ontario.  Dr. Vaage can be contacted by email:
Dr. Alan S. Vaage Ph.D.
September 26, 2016