Maintaining your Limestone Pelletizing Operation

This article was authored by:

Craig Peppin
Service & Lab Manager

An effective maintenance program is indispensable to sustaining an efficient, productive limestone pelletizing operation. While maintenance is often overlooked, it should always be incorporated as part of a facility’s regular operation procedures. Limestone pelletizer plant maintenance ensures equipment reliability, preserves a safe work environment, and detects minor problems before major issues develop. The following procedures are recommended to preserve limestone pelletizing equipment reliability.

Limestone Processing Maintenance

Choosing Suitable Limestone Pelletizing Equipment

The first step to proper limestone pelletizing maintenance is to employ equipment that is appropriately prepared to handle limestone. As experts in limestone pelletizing and equipment design, FEECO can engineer solutions to complement a variety of stages in a limestone pelletizer plant. Additionally, while special equipment customizations are not often required for standard limestone processes, FEECO has the ability to customize equipment to complement a customer’s specific processing needs if needed.

Reducing Limestone Build-Up

As with many other materials, a common limestone pelletizing issue is material build-up within the processing equipment. If left untreated, build-up could wear down equipment and result in equipment failure and costly down-time. Frequent removal of limestone should be performed on all equipment in order to prevent related issues.

Limestone Pelletizing Equipment Maintenance

Maintenance on limestone pelletizing equipment must be routinely performed to ensure consistent results from all components within a system. Considered to be a proactive measure in equipment care, regular maintenance supports equipment longevity and the overall dependability of a limestone pelletizing system. In addition, the following maintenance concerns should also be addressed:

  • While all equipment requires regular upkeep, limestone pin mixer maintenance is especially important. The action within a pin mixer results in a lot of wear on the equipment, making regular care and maintenance even more important to this process. Performing thorough limestone pin mixer maintenance promotes equipment longevity and processing consistency.
  • Similar to limestone pin mixer maintenance, limestone dryer maintenance is an important step in preventing unnecessary wear on equipment. An unforgiving natural material such as limestone rock can be abrasive on equipment. Consistent, thorough limestone dryer maintenance supports the equipment’s ability to continuously process mined limestone and allows operators to catch any minor issues before they escalate.

Regardless of the processing stage, all equipment should be regularly maintained in order to support individual machine performance and sustain a healthy pelletizing system overall. Outlined below are fundamental maintenance tips for commonly used limestone pelletizing equipment:

General Limestone Equipment Maintenance Recommendations

  • While performing maintenance procedures, always look for wear, damage, or any other signs of faulty equipment. Report any irregularities to the appropriate personnel and log the information in the equipment’s records. Do not operate damaged equipment.
  • Follow all safety procedures outlined in the original equipment manual, as well as any additional facility safety requirements.
  • Record all maintenance related activities, including inspections, lubrication, and adjustments.
  • Always follow regularly scheduled maintenance and lubrication programs recommended in the equipment manual.

Bulk Material Handling Equipment

Limestone Bucket Elevator Maintenance

  • Regular cleaning should be performed to thoroughly remove material build-up.
  • The two head bearings and the two boot take-up bearings should regularly be lubricated. Each of these four lubrication points should be serviced at least once a week.
  • The drive motor, speed reducer and couplings, and chain and sprocket or belt pulley should also be inspected and maintained per manufacturer’s recommendations.
  • Periodic inspections should be conducted on the following components: drive system chains; the elevator’s vertical position; the head and boot pulleys (to ensure the belt is centered); electrical wiring and its associated contacts and switches; and nuts and bolts (to ensure they are properly tightened).
  • It is especially important to clean out the boot after each use if the elevator is used seasonally to handle limestone. The equipment should be operated for a short period every two weeks to ensure belt flexibility is maintained.

Limestone Belt Conveyor Maintenance

  • Regular cleaning should be performed to thoroughly remove material build-up.
  • Periodic inspections should be conducted on the following: scraper mechanisms; belt tracking; idler wear; roll freeze; extended grease fittings; and the drive sprocket and chain.
  • Lubricate the following components as directed by manufacturer recommendations: bearings, idlers, motor, speed reducer, and drive chain or belt pulley.

Limestone Chain Mill Maintenance

  • Regular cleaning should be performed to thoroughly remove material build-up.
  • Lubricate the following components as directed by manufacturer recommendations: bearings and drive motor.
  • Regularly inspect internal components, checking chains and hardware for wear.

Pelletizing/Agglomeration Equipment

Limestone Disc Pelletizer Maintenance

  • Regular cleaning should be performed to thoroughly remove material build-up.
  • Lubricate the following components as directed by manufacturer recommendations: bearings, reducer, drive motor, motor slide shifting screw, and the ball oiler or oil hole (depending on which base is used).
  • Periodic inspections should be conducted on the following: bearings, reducer, drive motor, spray system, nozzle head, and spray tip.
  • Routinely inspect scrapers and plows. Worn or damaged scrapers/plows can lead to an uneven bed surface, which in turn can negatively affect the process.

Limestone Pin Mixer Maintenance

  • Regular cleaning should be performed to thoroughly remove material build-up.
  • Lubricate the following components as directed by manufacturer recommendations: assemblies, bearings, speed reducer and couplings, and screw conveyors and drive.
  • Periodic inspections should be conducted on the following: assemblies, bearings, v-belt, shaft, and shaft seal.
  • Periodically check clearance between pin tip and liner. The pins will wear over time and it is crucial to maintain original clearance. If clearance is too large, the pins will need to be adjusted or replaced.

Thermal Processing Equipment

Limestone Dryer Maintenance

  • Regular cleaning should be performed to thoroughly remove material build-up.
  • Periodic inspections should be conducted on the following: bearings, drive chains, couplings, hammers, motor, reducer, trunnion wheel/tire contact pattern, v-belts, burner system, internal devices, thrust assemblies, girth (bull) and pinion gears, and floating tire assemblies. In addition, the following contacts should be visually inspected: breeching seals; thrust rollers to tire and trunnion wheels to tires.
  • Lubricate the following components as directed by manufacturer recommendations: bearings, drive couplings, drive motor, thrust assemblies, floating tire assemblies, trunnion wheel bearings, and trunnion wheels and tires.
      • Girth/pinion gear
      • Trunion wheel/tire contact

Note: This is an overview and is not considered a complete maintenance list. Always consult your original equipment manual to ensure all necessary maintenance is followed.

For more information on limestone dryer maintenance, limestone pin mixer maintenance, or how FEECO’s knowledgeable service team can assist you with your limestone equipment maintenance, contact us today!

About the Author . . .


Craig Peppin is FEECO’s Customer Service Manager and Lab Manager.

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