39 www.drivesncontrols.com September 2026 FOOD AND BEVERAGE n Food and bev drive failures start at specification A geared motor on a packing line conveyor fails after just 14 months. It might then be replaced like-for-like, only to fail again after a similar timespan. A report into the failure blames water ingress, and suggests shorter inspection intervals as the corrective action. But two years later, drives in the same location are still failing. Maintenance cannot correct a specification error, only postpone it, but it often gets the blame. The tell is repeatability: maintenance failures will be scattered across locations and intervals, while specification failures cluster on the same position at similar running hours, across lines and sites, regardless of who looks after them. Five types of application account for a significant proportion of the most commonly reported problems. n Washdown conveyors A gearbox under load runs hot, and the air inside it expands. Wash it down and that air contracts, drawing in water and cleaning chemicals past the output seal, while the seal itself remains intact. Just a fraction of a percent of water in the oil can reduce rolling bearing lives to a quarter of their datasheet ratings. Caustic foam can attack aluminium and its anodising, chlorinated sanitiser can pit 304 stainless, and painted cast iron can fail at the edges. Housing materials needs a grade, not an adjective. n Spiral freezers and chilled halls The conflict here is in the seal compound. Fluoroelastomers shrug off an 80°C caustic wash, but go hard when temperatures drop below 20°C, while the nitrile that stays compliant in a freezer will not survive a wash. Oil viscosity chosen for a warm ambient is close to solid at –25°C, so bearings run dry through start-up. These drives fail after a defrost rather than in production, which sends investigators to the wrong place. n Fillers, cappers and seamers Indexing machinery applies peak torque several times its continuous rating, hundreds of times an hour, but selection by kilowatt rating and ratios takes no account of that fact. Bearing life falls with roughly the cube of the load, so a load that is a fifth above the assumed value costs about 40% of calculated life. The first symptom is not mechanical: backlash grows, fill weights drift, and the line is investigated as a quality problem for months. These are the mathematical realities. n Augers, mixers and dividers Powder and paste handling are breakout problems. Flour or milk powder standing over a weekend can require a starting torque way above the running duty, and screws coupled straight to the output shaft add an overhung load that is often overlooked. Size on running torque alone and the failure arrives as a fatigued shaft at the keyway or a collapsed output bearing. n Ovens, proofers and retorts Ambient is the forgotten line. A drive rated at 40°C and installed at 55°C beside an oven exit loses much of its thermal headroom, and grease life roughly halves for every 15°C above its design point. Nothing here looks like a specification fault, but that’s exactly what it is. The pertinent questions All of the above failures can be avoided in one conversation – provided that it happens before the drive reaches the bill-of-materials stage, and involves someone who knows the application rather than the data in a catalogue. The test is which way the questions run. What is the breakout torque after a weekend standstill, rather than the running torque? How many starts an hour, against what inertia? What is in the cleaning chemistry, at what temperature and how often? What is the ambient temperature at the mounting position rather than in the room, and which way up will the drive sit once the hygienic frame is fixed? If none of those questions are answered, you are buying a kilowatt and a ratio, not a drive for the duty. Specified properly, you pay for a drive once. Specified badly, it is paid for every 14 months, for the life of the machine – by someone who did not make the decision. n Drives on food and beverage lines have a reputation for having short lives – and poor maintenance is usually blamed. But according to Joe White, engineering design manager at Brown GearTech, these failures are often determined by decisions at the specification stage. Geared motor failures are common on conveyors subject to washdown processes
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