Picture a factory conveyor belt that isn’t working correctly. Perhaps product is jamming or spilling, and an operator is making frequent adjustments or attending to blockages. This isn’t just inefficient, it’s potentially dangerous and it needs addressing quickly.
Less hazardous but perhaps just as disruptive, a broken down conveyor quickly brings other machinery, possibly even entire lines or departments, to a halt. That will have a big impact on efficiency and utilization metrics such as OEE and, ultimately, hits financial performance and profitability.
These scenarios are avoided by performing regular and effective conveyor belt maintenance. This blog reviews the importance of conveyor maintenance and identifies some useful tools and techniques. It wraps up with some recommendations for a preventive maintenance program and a list of belt maintenance points to check.
Why conveyor belt maintenance is critical
Many manufacturers rely on factory conveyor systems for efficient material flow. Any unplanned stoppage is disruptive and costly, requiring immediate attention from the maintenance team. As noted previously, problems with a belt, while they may not stop it running, can create serious safety hazards.
A troublesome conveyor belt — perhaps it’s not moving smoothly, or it’s pushing product against rails and guards — can also lead to waste. For example:
- Containers might get marked and subsequently be rejected
- Liquids could spill, transferring to adjacent containers and dripping onto the floor to cause slip hazards
- Dry packaging can get torn open
Conveyors come to a halt when either the belt or the drive system fails. However, these rarely happen without warning. More typically, there’s misalignment or slippage that creates wear, or dirt or contamination that increases friction, reduces airflow and causes overheating. Sometimes operators will report an unusual noise, smell or vibration, all of which signal a need for conveyor servicing.
Machine health monitoring for conveyor belt systems
Regular inspections are an important part of conveyor belt maintenance, but they can leave a long period between when a problem arises and when it’s discovered. This is where machine health monitoring has an important role.
Machine health monitoring entails instrumenting a piece of equipment with sensors that monitor key aspects of its performance or condition. Data captured by these sensors is compared against preset limits and analyzed for trends, sometimes on the machine itself, but more often away from the production floor.
Conveyor system characteristics that can be monitored include:
- Belt tension
- Belt speed
- Belt vibration
- Motor and gearbox/reduction drive temperatures
- Motor current draw
- Motor and gearbox/reduction drive vibration
- Gearbox oil condition
For these and other characteristics, it’s useful to set alarms for when limits are exceeded as this will signal that conveyor repair is needed. A bigger benefit is realized though from monitoring trends and anticipating when failure might occur. This kind of predictive maintenance has two big benefits: it prevents unplanned downtime, and it allows work to be scheduled for a time that’s convenient for production, rather than requiring a belt shutdown.
Common conveyor belt maintenance tasks
Conveyor system maintenance involves four main activities — inspection, lubrication, adjustment and cleaning. Here’s a closer look:
- Visual inspection of the belt: Check for signs of wear that can indicate rubbing against a guard or guide. (This often stems from misalignment.) Belt damage can also result from it being overloaded or tensioned incorrectly (which may cause cupping of the edges). Conveyors used for transporting bulk material can suffer from carryback (where material sticks to the belt), which should be removed by a scraper on the underside.
- Lubrication: Mechanical lubrication applies to both rollers and bearings, and any reduction drive or gearbox used. The former should be checked for free rotation and greased or replaced as needed, while in the latter it’s important to check fluid levels, condition and temperature.
- Tension adjustments: Conveyor belts and drive belts will stretch in use. Tension should be checked and adjusted as needed to prevent slippage and ensure smooth operation. (Ambient temperatures can also affect tension, so if an adjustment is made when the factory is very hot it should be rechecked when conditions are cooler.)
- Component inspections: Examine drive motors, pulleys, v-belts, pulley lagging and idlers for signs of wear or malfunction.
- Cleaning: Ensure the belt and any scrapers are clean and fit for use. Remove any buildup of dust or dirt from ventilation grills and fan blades to ensure an adequate flow of cooling air.
Preventing common conveyor belt issues
Preventive maintenance (PM) is essential for avoiding unplanned breakdowns and stoppages, and for preventing conveyor-related accidents. Three points to include in a conveyor PM program are:
- Belt slippage: Belts can slip on the head or drive pulley, particularly if the load varies suddenly and especially if the pulley lagging is in poor condition. As this can lead to product losses and increased wear in drive system components, it’s important to tension the belt correctly and replace lagging as needed.
- Mistracking: A belt that’s not set square within the frame will move over to one side and start to rub. This will accelerate wear and shorten belt life. It may also put product in a less-than-optimal position for automated unloading. Pulley alignment and belt tension are the keys to preventing tracking problems.
- Excessive wear: Regular inspections are essential to detect belt wear early, so conveyor repair can be initiated before it causes problems.
Conveyor belt maintenance checklist
Essential elements of conveyor belt PM are:
- Daily checks: Inspect belt alignment, check for damage, abnormal noise or vibration, ensure material isn’t building up anywhere.
- Weekly: Lubricate key components, inspect for wear, check belt tension, clean as necessary. In a plant with multiple factory conveyor systems industrial lubrication services can reduce the maintenance team’s workload and ensure this isn’t skipped.
- Monthly: Perform in-depth inspections of belt integrity, pulley conditions and safety mechanisms. For large and heavy-duty gearboxes and reduction drives, consider investing in lubrication analysis to detect signs of wear or oil breakdown.
- Quarterly/annual maintenance: Conduct detailed system assessments, replace worn components, adjust and recalibrate photo eyes and other sensors.
Support and resources for industrial maintenance
Conveyors are an essential, though often overlooked and underappreciated, piece of equipment in many factories. Regular PM reduces breakdowns, conveyor-related safety hazards and handling-related waste, although health monitoring and predictive maintenance do more to ensure high levels of availability.
ATS helps manufacturers across many industries improve the effectiveness of their maintenance operations. Our services range from short and long-term support to address maintenance backlogs or excessive downtime to help with implementing machine health monitoring. Increasingly, manufacturers use our predictive maintenance services to raise efficiency and productivity by cutting both planned and unplanned downtime. Contact us to learn what we could do for your business.
