Routine maintenance of particle size reduction equipment is integral for production facilities, which is why various methods for managing maintenance have been developed. Conducting regular servicing and maintenance ensures manufacturers experience as little downtime as possible.

Whether it’s lump breakers, hammer mills, fine grinders, air classifying mills, or other machinery for particle size reduction, equipment requires maintenance on a routine basis to ensure top performance. While this can be done as needed, this often results in unplanned downtime and production interruptions. Regularly scheduled inspections and maintenance of particle size reduction equipment helps manufacturers prevent unscheduled downtime, which can eat into profits by reducing a plant’s productivity.

The Importance of Maintenance for Particle Size Reduction Equipment

Properly functioning particle size reduction equipment is necessary to meet production goals for processing facilities. Should machinery malfunction, the costs associated with equipment failure are more than just the price of repairing machinery, outsourced technicians, and spare parts.

When equipment breakdowns occur, it increases the cost of production across the board. Lost production time leads to delayed shipments and unhappy customers. Labor costs increase as inoperable machinery results in the machine’s operators being unable to keep production going. Equipment that doesn’t perform as expected can also lead to an unsafe work environment.

Types of industrial maintenance include:

  • Reactive maintenance involves repairing equipment only once it breaks down, which often results in loss of efficiency and premature failures, though it saves on costs in the short term.
  • Preventive maintenance involves carrying out routine tasks to maintain equipment to prevent unplanned downtime caused by breakdowns through inspecting and repairing machinery when it shows signs of failure.
  • Predictive maintenance involves combining data with techniques and tools that help analyze the condition of machinery, often including maintenance schedules to carry out repairs to avoid unplanned downtime caused by equipment failure.

Typical Issues with Particle Size Reduction Equipment

Identifying potential signs of equipment failure allows operators to resolve mechanical concerns before they become more significant problems. Additionally, tracking issues with particle size reduction equipment will enable manufacturers to better plan maintenance work, which means less downtime and a more productive facility. When looking to resolve issues with machinery used for reducing material, there are certain basic things for which manufacturers should look out.

Parts Wearing Out Too Quickly

If machinery wears too much during particle size reduction, testing should be done to discern which parts are wearing the most. Through crushing tests, it can then be determined how machinery handles material properties like abrasiveness, friability, heat sensitivity, and plasticity.

This will help determine the following:

  • Changes to moisture content that can affect material properties
  • Energy used during processing
  • Frequency with which parts must be replaced
  • Particle size distribution prior to and following reduction

During these tests, it’s important to look for patterns in how components wear to address possible issues with feeding or discharging material.

High Energy Costs

In some instances, improper feeding can lead to higher energy costs that affect particle size reduction. Equipment often uses more energy if material hits the rotor directly and enters the grinding chamber from an incorrect angle. This can also happen when material isn’t evenly distributed across the grinding implement’s face. When processing material, it’s best to utilize a single machine for particle size reduction, which tends to save on costs and enhance processing quality. Also, manufacturers may benefit from machinery capable of producing a narrower particle size range requiring less downstream processing.  

High Labor Costs

When workers are spending an inordinate amount of time unclogging machinery, there’s likely to be a problem. This may be due to moisture causing material to build up internally, resulting in more time spent cleaning and maintaining equipment. If this occurs at the chute feeding the machine, mitigating this may require a heater to dry material so that it slides off more easily into the grinding chamber. Sometimes creating more airflow can also release material that gets stuck against internal plates or grinding implements.  


Screens help remove correctly sized particles from material during particle size reduction. Equipment wear can be reduced by keeping all screens clean and well-maintained. Not only will this increase productivity, but it also improves the quality of the end product.

High Maintenance Costs for Equipment

Certain particle size reduction equipment requires more maintenance. It’s important to ensure that the best type of machinery is used for specific materials and applications. If there’s a question about what equipment will work best, contact our experts.

Underused Machinery

Not everything needs to be processed in-house, especially when there’s only an intermittent need. For certain activities, manufacturers of particle size reduction equipment may be able to offer toll processing services. This negates the need for expensive maintenance and can be used when developing new processes or products before purchasing new equipment.

Dangerous Equipment

There can be serious safety concerns for certain applications in which very fine dust particles become airborne during processing. Such material can explode or otherwise catch fire, so implements that protect against conflagrations must be properly inspected and maintained. In some cases, it may mean replacing a rotary airlock with one specifically designed for dust collection.

Proper Servicing

Because of the relatively high expense of the machinery used in particle size reduction, equipment is generally made to last for decades as long as it’s properly maintained. Reputable manufacturers will ensure their machines come with warranties, and many also offer maintenance agreements. Documenting installation dates, commissioning activities, and any manufacturer-directed training is important. Additionally, keeping spares of the components most likely to wear to keep equipment in good working condition is a good idea. A reliable manufacturer that can provide 24/7 service and work with customers to address emergencies and immediate safety concerns is also invaluable.    

When to Replace Specific Components

Anything with moving parts requires routine maintenance so that it performs optimally, and this is particularly so for machinery used in particle size reduction. Equipment with grinding elements will wear out the more it’s used, so conducting regular inspections is essential.

When it comes to particle size reduction, the equipment can be assessed by:

  • Monitoring and analyzing vibration levels to identify patterns.
  • Number of hours since last servicing.
  • Regularly scheduled inspections and maintenance.
  • Total hours machinery has run.

It’s important to identify what causes breakdowns of equipment used for reducing particle size and then work towards resolving these issues. This involves setting firm dates for maintenance and keeping an inventory of vital components on hand to ensure equipment stays in top condition.

Inspection & Replacement of Worn Components

Periodic inspections of equipment, along with an inventory of key parts, help manufacturers avoid downtime.

When replacing components for particle size reduction equipment, consider the following examples:

  • Bearings: Should a bearing begin to give off too much heat, it causes the outer ring to spin, resulting in vibrations within the housing, or else unusual squeaking noises from the bearing; as bearings support the weight of the rotor, it’s also recommended that they’re swapped out in pairs.
  • Hammer rods: Each time the hammers are rotated, the hammer rods should be inspected, replacing them once becoming grooved.
  • Hammers: Once cutting edges become well-rounded, hammers lose their efficiency to reduce particle size; reduction equipment featuring hammers – whether 4-way or 2-way reversible – should be replaced in sets that have been factory-balanced, but only once all cutting edges have been worn.
  • Screens (or bar grates): Essential for determining final particle size, reduction equipment should replace screens or bar grates when the perforations on screens are sufficiently lengthened, or the bar edges of grates become too smooth.
  • Wear plates: Commonly used in the processing of abrasive or hard-to-mill material, these plates protect the mill’s housing and prevent a mill from prematurely breaking down; when wear plates exhibit signs that they’re becoming too thin, they should be replaced with thinning around the bolts an early indicator.

Prater Industries: Parts for Particle Size Reduction Equipment

To ensure continuous and efficient operation, Prater Industries recommends that customers keep an inventory of important spare parts to minimize downtime should necessary maintenance or a breakdown occurs. This ensures that production lines aren’t interrupted, and machinery will continue reducing material particle size. Reduction equipment should keep the most vital components on hand to prevent manufacturers from experiencing lengthy downtime. To learn more about best practices regarding routine maintenance of particle reduction equipment, or to order parts for your machine, contact the experts at Prater today.