Lubrication Maintenance: Where to Oil and How Often

Why Lubricate?

Machines have many parts that rub against each other: shafts and bearings, chains and sprockets, gears and gears, slide blocks and rails. Lubricating oil or grease forms a film between them that reduces wear, lowers temperature, and prevents rust. With insufficient lubrication, parts wear faster, noise increases, motor load rises, and eventually the machine has to be stopped for repair.

Food machinery has one more concern than general machinery: lubricants must not contaminate food. Article 7 of the Standards for Food Factory Construction and Equipment (食品工廠建築及設備設廠標準) requires food machinery to be constructed so as to keep lubricating oil, metal fragments, wastewater, and other potentially contaminating substances out of products. So lubrication should be "plenty where it's needed, and not a single drop where it doesn't belong."

Lubrication Points

Common lubrication points on food machinery (actual locations for each model are in the manufacturer's manual):

• Bearings: Bearings for motors, drums, and conveyor rollers; some are sealed and maintenance-free, others have grease nipples.
• Chains and sprockets: Drive chains need regular oiling and tension checks.
• Gears and gear reducers: Gear reducers contain gear oil, and the oil level should be checked and the oil changed regularly.
• Slide rails and guide rods: Reciprocating mechanisms, such as cutting, forming, and tray-feeding mechanisms.
• Cams and linkages: Mechanisms that control the timing of motions.
• Pneumatic components: Some cylinders need a lubricator, while others are non-lube types.

What usually doesn't need oil, and shouldn't get any, are food-contact surfaces such as the inner walls of the hopper, the screw surface, the nozzle, and the conveyor belt surface. If these areas need anti-stick or release treatment, what's used is a food-safe oil or release agent, which is a separate matter from mechanical lubrication.

How Often to Oil

There's no universal answer to this; it depends on:

• The manufacturer's lubrication chart: The most important reference. A proper equipment manual lists the location, lubricant type, amount, and frequency for every lubrication point.
• Running hours: Running 4 hours a day versus 20 hours calls for different frequencies.
• Environment: Machines in humid or cold conditions (near freezers) or that are washed frequently lose lubricant faster and may need more frequent oiling.
• Washing method: Each wash with water or detergent may strip the oil film from some lubrication points.

In practice, you can divide lubrication points into daily, weekly, monthly, and yearly, make a lubrication checklist, post it by the machine, and sign off when done. If the manual is lost, ask the equipment maker for one; don't oil by feel. For the lubrication items on Dong-Yih Machinery models, call us at 06-257-4644.

What Happens with Too Much Oil?

Many people think "a bit more is safer," but it's actually the opposite:

• Overflow and dripping: Excess oil gets flung off or drips, and may land on products or food-contact surfaces.
• Attracting dust: Flour and dusting powder stick to the oil and form sludge, which increases wear and becomes a breeding ground for microorganisms.
• Bearing overheating: A bearing packed with too much grease has more churning resistance when running, so its temperature actually rises.
• Waste and cleaning burden: It takes more effort to degrease during cleaning.

U.S. federal regulation 21 CFR 178.3570 also requires that lubricants with incidental food contact be used in the minimum amount needed to achieve the technical effect.

Lubrication Safety and Hygiene

• Stop before oiling: Article 46 of the Occupational Safety and Health Facilities Rules (職業安全衛生設施規則) requires bearings in power transmission equipment to be properly lubricated and prohibits oiling while running, except where a safe oiling device is fitted; Article 57 requires stopping operation and locking out and tagging out when oiling.
• Use the right oil: Near food areas and on parts that may have incidental food contact, use food-grade lubricants (such as NSF H1). See What Is Food-Grade Lubricant (NSF H1)?
• Dedicated tools: Keep grease guns and oil brushes dedicated and labeled, and don't store them with food tools.
• Wipe off excess: After oiling, wipe away any overflow.
• Record: Note the date, location, lubricant, amount, and person.

FAQ

Q: Where do food machines need oil?
A: Commonly at bearings, chains, gear reducers, slide rails and guide rods, cams and linkages, and other drive parts; actual locations are in the manufacturer's manual.

Q: How often should I oil?
A: Follow the manufacturer's lubrication chart, adjusted for running hours, environment, and washing frequency.

Q: Is it safer to use a bit more oil?
A: No. Excess oil drips and contaminates products, attracts dust, and can make bearings overheat.

Q: Can I oil the machine while it's running?
A: No. Article 46 of the Occupational Safety and Health Facilities Rules prohibits oiling while running (except where a safe oiling device is fitted).