What an inspection is for
An inspection is a structured look at a machine while it is either running or safely stopped, aimed at finding trouble while it is still small. It is different from maintenance work. The inspector’s job is mainly to notice and report; fixing comes afterward, often as a planned task.
Conveyors reward this approach more than most machines. They are long, they have many repeated parts, and a fault in one roller or one splice can stop an entire line. They also run close to people, so a missing guard or a failed emergency stop is a safety problem, not just an inconvenience.
How often to inspect
There is no universal frequency. A common pattern is a quick operator look at the start of each shift, a more thorough walk-down weekly or monthly, and a detailed inspection with the conveyor stopped and isolated at longer intervals. Heavily loaded, dusty, wet or around-the-clock conveyors typically deserve more frequent checks. Start with the manufacturer’s recommendations and adjust based on what your own records show.
Before you go near it
Looking at a running conveyor from a safe walkway is one thing; reaching into it is another. Anything that involves touching, cleaning, adjusting or removing a guard should be done only after the conveyor has been stopped and isolated under your site’s lockout tagout procedure. Conveyors can start unexpectedly, can hold stored energy in tensioning systems, and can have loaded belts that move when brakes or drives are released. Follow the manufacturer’s manual, local regulations and your site’s written procedures, and let only trained personnel do work inside the machine.
The walk-down, item by item
The belt or chain
Look along the whole length for:
- cuts, gouges, frayed edges, cracked or worn covers
- damaged or separating splices and fasteners
- material buildup on the belt surface
- signs of slipping, such as shiny worn patches on the drive pulley area or smell of hot rubber
- for chain conveyors, stiff or elongated links, missing pins and signs of rust or dryness
Belt edge damage is often a clue to a tracking problem, which is covered below.
Tracking
A belt should run roughly centered. Drift to one side, especially if it is getting worse, can be caused by uneven loading, buildup on rollers, misaligned rollers or frames, or worn parts. Belts that rub against the frame wear their edges quickly. Note where along the conveyor the belt moves off center, because the cause is usually near that spot.
Rollers and idlers
Rollers should turn freely. Walk the line and listen for squeals, rumbles or clicks. Look for rollers that are not turning, since a seized roller wears a flat spot and eventually damages the belt. Feel for unusually warm housings only when it is safe to do so, and avoid touching moving parts. Missing rollers, bent frames and loose brackets also belong on your list.
Pulleys, drives and take-up
Check the head and tail pulleys for lagging wear, buildup and damage. Look at the drive for oil leaks, loose guards, unusual noise or heat, and loose mounting bolts. The take-up, which keeps tension on the belt, should be neither bottomed out nor excessively stretched. A take-up near the end of its travel is a sign the belt has stretched and may need to be shortened or replaced. Where the drive uses belt drives or chain drives, look at their tension and wear too.
Skirts, scrapers and transfer points
These are the places where material spills. Look at skirting rubber for wear and gaps, scrapers and cleaners for contact and wear, and transfer chutes for buildup or blockages. Spillage is not just untidy; it jams rollers, fouls bearings and can pose a slipping hazard.
Guards
Every nip point, rotating shaft, drive and exposed moving part should have its guard in place, secure and undamaged. A guard found removed or loose should be reported immediately and not simply put back without finding out why it was off. Check that guards are not rubbing on moving parts.
Emergency stops and safety devices
Emergency stops such as pull cords and push buttons must be reachable and unobstructed. Many sites test them on a schedule by actually triggering them, with proper authorization and in a controlled way, and recording the result. The underlying emergency stop circuits are designed so that a fault should cause a stop, but only testing proves the whole chain works. Also check other protective devices such as belt misalignment switches, zero-speed switches, overload devices and limit switches. If any of these is bypassed, damaged or not responding, treat it as an urgent issue.
Electrical and controls
Look for damaged or loose cables, open enclosures, signs of overheating and moisture, and warning lights that are on. Do not open electrical enclosures unless you are qualified and authorized.
Structure and walkways
Check for loose or missing fasteners, cracked welds, corrosion, damaged supports, blocked access and housekeeping hazards around the conveyor.
Sights, sounds and smells that matter
Beyond a checklist, the senses are valuable. New noises, new vibration, a different pattern of spillage, a warm smell, or belt edges that look different from last week are classic early warning signs. Experienced operators often notice these before any instrument does, so it is worth encouraging them to say something even when they cannot explain it.
Recording what you find
An inspection that is not written down is hard to act on. A simple form or checklist with the item, the finding and the location works well, and a photo can help. Record the severity in plain terms, such as “monitor”, “fix at next planned stop” or “stop and repair now,” so the next person knows how urgent it is. Over time the records show repeat problems, like the same transfer point spilling every month, which may point to a design or adjustment issue and not just a cleaning one.
Reports should become work orders rather than being left in a notebook, and open items should be reviewed at a regular meeting so nothing quietly lingers.
A note on different designs
The checklist above is written mainly with belt conveyors in mind. Roller, screw, chain, bucket and overhead designs share the same logic but have their own wear points. Always use the manufacturer’s inspection guidance for the specific design you have.
This is general information, not engineering advice. Follow your site’s procedures and applicable regulations.