A Detailed Conveyor Belt Preventive Maintenance Checklist

Conveyor systems operate under continuous load, handling varying speeds, belt tensions, misalignment risks, and material buildup. Without routine inspection, even minor faults—like worn idlers, loose drive chains, or seized bearings—can escalate into system-wide failures. A preventive maintenance checklist addresses these technical weak points before they impact performance.

Below, we break down the checklist into specific focus areas such as mechanical components, belt condition, lubrication, etc. and also offer practical tips for carrying out the maintenance of conveyor systems. With this comprehensive conveyor maintenance checklist at their disposal, your maintenance team can thoroughly inspect the conveyor systems and successfully extend their lifespan.

What is a Conveyor Preventive Maintenance Checklist?

A conveyor preventive maintenance checklist is a detailed list of specific inspection points and maintenance tasks focused on the components and functions of a conveyor system. It outlines routine checks and actions required to maintain the conveyor’s operational condition, covering parts such as belts, rollers, motors, bearings, and safety mechanisms.

What are the Benefits of a Conveyor Belt Preventive Maintenance Checklist?

A preventive maintenance checklist designed for conveyor systems brings clear advantages that address the specific demands of these mechanical setups. A comprehensive maintenance checklist for conveyor systems:

• Prevents Belt Failures and Misalignment

  Conveyor belts rely heavily on belts running smoothly over rollers and pulleys. Regular maintenance and inspection through a checklist helps detect belt wear, fraying, or misalignment, maintaining the efficiency of material handling operations.

• Keeps Rollers and Bearings in Optimal Condition

  Rollers and bearings handle constant load and friction. Checking for signs of wear, lubrication needs, or damage prevents roller seizure and bearing failure that would halt conveyor operation and ultimately the actions minimize downtime.

• Avoids Motor and Drive Component Overload

  Overloading is one of the common conveyor belt issues that creates pressure on the motor. Proper maintenance focused on checking motor temperature, vibration, and drive tension reduces the risk of motor burnout or drive chain failure and there are no costly repairs.

• Maintains Proper Tracking and Tension

  Conveyor belts need precise tracking and tension adjustments to avoid belt drifting or excessive slack. Using the checklist to monitor and adjust these parameters prevents uneven wear and potential system jams.

• Minimizes Material Spillage and Contamination

  Checking guards, scrapers, and covers limits spillage of materials and contamination, protecting product quality and reducing cleanup costs.

• Reduces Safety Risks

  Conveyor systems have many exposed moving parts like pinch points and rotating rollers. Regular checklist-based inspections help identify missing guards or loose components that pose hazards to workers.

Conveyor Preventive Maintenance Checklist

1. Belt Components

• Belt Surface and Physical Condition
  • Visually inspect for cuts, tears, cracks, or frayed edges.
  • Check for abnormal belt wear across the width (center vs. edges).
  • Look for signs of belt cupping or curling.
  • Inspect both top and bottom surfaces of the belt.
  • Verify if belt thickness is uniform along its length.
  • Check for material buildup or sticking on the belt surface.
  • Remove any foreign objects trapped between belt and structure.
    

• Belt Tension
  • Check belt tension during operation and idle state.
  • Adjust tensioning mechanism as per manufacturer specs.
  • Ensure there’s no belt slippage during start-up or under load.
  • Verify belt sag doesn’t exceed permissible limits.
    

• Belt Tracking & Alignment
  • Observe belt alignment throughout the entire length.
  • Confirm that the belt runs centrally on all pulleys and idlers.
  • Adjust training idlers or snub pulleys if belt tracks off-center.
  • Inspect for signs of rubbing against structural elements.
  • Check belt edge wear and mark for future movement tracking.
    

• Belt Splices and Joints
  • Inspect mechanical fasteners for wear, looseness, or damage.
  • Check vulcanized splices for cracks, peeling, or separation.
  • Verify fastener retention torque if bolted joints are used.
  • Look for belt lacing failures or mismatches.
  • Replace or reinforce weakened splices immediately.
    

• Belt Cleaning Contact
  • Inspect if belt cleaners/scrapers are contacting the belt evenly.
  • Verify that cleaning blades are not scoring or damaging the belt.
  • Ensure the return belt surface is free from residual material buildup.

2. Drive System

• Drive Motor
  • Inspect motor casing for cracks, overheating marks, or dust ingress.
  • Check for unusual noise or vibration during operation.
  • Verify motor terminal connections for tightness and signs of arcing.
  • Measure and record motor running current and compare with nameplate.
  • Check motor cooling fans and clean air inlets/outlets.
  • Confirm that the motor mounting bolts are secure and show no movement.
  • Look for oil leaks if the motor is oil-cooled or integrated with a gearbox.
    

• Gear Reducer / Gearbox
  • Check oil level through sight glass or dipstick.
  • Inspect gearbox for oil leaks, rust, or surface corrosion.
  • Listen for grinding or knocking noises indicating internal wear.
  • Check for proper venting—ensure breather plugs are not clogged.
  • Verify that gearbox mounting bolts are tight.
  • Record gearbox temperature during full-load operation.
    

• Drive Pulley and Couplings
  • Inspect pulley shells for cracks, grooves, or wear patterns.
  • Examine lagging for detachment, delamination, or uneven wear.
  • Check for signs of belt slippage on the drive pulley face.
  • Measure and record pulley alignment with laser or straight edge.
  • Inspect keyway and locking assembly for looseness.
  • Examine flexible couplings for cracks, misalignment, or dust buildup.
    

• Drive Chain / V-Belt (if applicable)
  • Inspect drive chain for elongation, corrosion, or broken links.
  • Measure chain tension and compare with manufacturer’s limits.
  • Lubricate chain as per maintenance plan – wipe off excess lubricant.
  • Examine sprocket teeth for wear or misalignment.
  • For V-belts, check for cracks, glazing, or side-wall wear.
  • Measure belt deflection and tension using a tension gauge.
  • Replace V-belts or chains if mismatched or if the set is incomplete.

• Electrical Drive Components
  • Inspect contactors and relays for wear and pitting.
  • Check frequency drive (VFD) for overheating or fault codes.
  • Test motor protection devices (overload relays, thermistors).
  • Clean drive panel filters and ventilation systems.
  • Confirm grounding of drive motor and panel is intact.
    

3. Pulley System

• Head Pulley
  • Visually inspect for signs of material buildup or imbalance.
  • Check for uneven wear across the pulley face.
  • Verify axial runout using a dial indicator.
  • Listen for abnormal noise indicating possible internal faults.
  • Ensure the pulley shaft is not bent or loose in its housing.
  • Inspect end discs for cracks or fatigue signs.
    

• Tail Pulley
  • Inspect pulley face for wear or grooving from return-side friction.
  • Check for material entrapment between pulley and belt.
  • Measure pulley concentricity during rotation.
  • Examine shaft locking mechanism and confirm torque values.
  • Inspect pulley support bearings for lubrication condition.
    

• Snub Pulley
  • Confirm that the snub pulley is applying the correct tension angle.
  • Look for misalignment leading to belt tracking issues.
  • Check for structural damage to pulley brackets or supports.
  • Inspect lagging surface for embedded material or scoring marks.
    

• Bend Pulley
  • Verify that the belt wraps fully without slipping.
  • Inspect for axial movement or excessive end float.
  • Ensure the pulley guard is intact and properly fastened.
    

• Pulley Bearings
  • Check bearing housings for visible oil or grease leakage.
  • Feel housing temperature during full-load operation.
  • Listen for clicking or grinding noises indicating failure.
  • Re-lubricate bearings per OEM schedule—avoid over-greasing.
  • Inspect bearing seals and replace if cracked or missing.
  • Confirm that set screws or locking collars are fully engaged.
    

• Lagging Condition
  • Check for lagging delamination or cracking.
  • Measure lagging wear depth and compare with replacement criteria.
  • Clean rubber lagging surface—remove any sticky debris.
  • Inspect for signs of chemical or heat damage on the lagging.
  • Confirm that ceramic lagging blocks (if used) are intact and secure.

4. Idlers and Rollers

• Carrying Idlers
  • Spin rollers manually to check for rough rotation or noise.
  • Inspect roller shells for dents, warping, or excessive wear.
  • Verify consistent contact with the belt along the entire line.
  • Check if any idler frames are bent, loose, or misaligned.
  • Look for seized or flat-spotted rollers.
  • Ensure that brackets and mounts are properly torqued.
    

• Return Idlers
  • Examine return rollers for caked-on material or belt residue.
  • Rotate rollers to check for eccentric movement.
  • Inspect brackets for rust, cracks, or misalignment.
  • Confirm clearance between the return side of belt and structure.
  • Replace worn-out or damaged rollers immediately.
    

• Impact Idlers (at loading zones)
  • Inspect rubber rings/discs for cracks, wear and tears, or looseness.
  • Check for proper spacing and correct number of impact rollers.
  • Ensure idlers are absorbing impact and not bouncing.
  • Inspect support frames and clamps for looseness or corrosion.
  • Verify structural integrity of the frame beneath the impact area.
    

• Troughing Idlers
  • Measure angle of trough frames to confirm it matches design spec.
  • Check for consistent belt contact across all three rollers.
  • Inspect center and wing rollers for uneven rotation or drag.
  • Confirm frames are securely bolted and show no shifting.
    

• Training Idlers
  • Check responsiveness of self-aligning rollers to belt movement.
  • Observe if they are actively correcting belt misalignment.
  • Verify that training frames move freely but are not loose.
  • Lubricate pivot points if applicable.
    

• Transition Idlers
  • Inspect alignment at transition zones (tail to trough).
  • Check for belt stress or twisting caused by incorrect transition distance.
  • Ensure transition idlers are not causing belt lift or flap.
    

• Lubrication of Roller Bearings (if applicable)
  • Check for dry bearing noise or signs of overheating.
  • Apply the correct lubricant quantity at prescribed intervals.
  • Mark rollers for the last service date using color tags or inspection sheets.
    

5. Take-up System

• Take-up Frame & Structure
  • Inspect take-up frame for cracks, corrosion, or structural deformation.
  • Check alignment of frame with conveyor centerline.
  • Verify that the frame is not binding or rubbing against any structural component.
  • Examine welds, bolts, and joints for fatigue or loosening.
    

• Gravity Take-up (if applicable)
  • Inspect take-up pulley for free vertical movement.
  • Confirm that the counterweight moves smoothly without jerks.
  • Check guide rails for straightness, damage, or obstructions.
  • Ensure counterweight does not bottom out or over-travel.
  • Inspect wire ropes or chains used to suspend the counterweight.
  • Verify that limit stops or bumpers are in place and functional.
    

• Screw Take-up
  • Inspect screw threads for rust, bending, or jamming.
  • Lubricate screw shafts with anti-seize or specified lubricant.
  • Verify equal adjustment on both sides to avoid belt misalignment.
  • Measure screw extension to ensure it’s within travel limits.
  • Check locking nuts or plates for tightness.

• Hydraulic or Pneumatic Take-up (if applicable)
  • Inspect cylinders for seal leaks or scoring.
  • Check pressure gauge readings against design specifications.
  • Examine hoses and fittings for cracks or leaks.
  • Test pressure accumulator (if installed) for charge levels.
  • Confirm take-up movement is smooth under load changes.
    

• Pulley & Bearings in Take-up System
  • Visually inspect pulley shells for wear, debris, or grooving.
  • Confirm that pulley rotates freely without resistance or noise.
  • Check bearing mounting bolts and structural supports.
  • Monitor bearing temperature during operation.
  • Verify proper greasing and inspect for leakage or contamination.

• Travel & Range
  • Confirm that take-up travel range meets belt tension requirements.
  • Mark current travel position and track over time for abnormal shifts.
  • Clean take-up travel path of dirt, obstructions, or buildup.
  • Check that travel range limit switches (if present) function correctly.

6. Loading and Unloading Systems

• Loading Chutes & Hoppers
  • Inspect liners (rubber, ceramic, or steel) for wear or detachment.
  • Check for material build-up that could restrict flow.
  • Verify that the chute profile directs material centrally onto the belt.
  • Examine structural welds and fasteners for fatigue or loosening.
  • Inspect skirt board sealing area for leaks or misalignment.
  • Check for blockages at discharge points or corners.
  • Confirm that dust suppression devices (foggers or water sprays) are functional.
    

• Skirt Sealing System
  • Inspect skirt rubber or polyurethane sealing strips for wear, cuts, or gaps.
  • Adjust skirting to maintain light, uniform pressure against the belt.
  • Ensure clamps, bolts, and skirt holders are not loose or missing.
  • Check for dust or fines escaping the skirt area—adjust seal if needed.
  • Replace hard, brittle, or glazed skirt material as needed.
    

• Belt Load Zone
  • Observe loading pattern—material should land on the belt centerline.
  • Inspect support structure for impact and deformation.
  • Check for material spillage or uneven loading leading to belt sway.
  • Confirm that the belt is not overloaded at start-up or shut-down sequences.
  • Monitor belt speed versus material feed rate for synchronization.
    

• Discharge Chutes
  • Inspect chute liners for erosion, gouging, or detachment.
  • Confirm proper direction of material flow into bins, crushers, or transfer belts.
  • Ensure flow diverters (if any) are operating smoothly.
  • Check that discharge angles prevent backflow or plugging.
  • Examine support frames for looseness, rust, or cracks.
    

• Belt Ploughs / V-Ploughs
  • Inspect plough blades for wear, uneven edges, or detachment.
  • Confirm plough is adjusted correctly to contact the belt without excessive pressure.
  • Check frame mounts and pivot points for looseness or binding.
  • Remove any material build-up around plough assembly.
  • Lubricate moving parts (if applicable) on rotating or floating ploughs.
    

• Transfer Points
  • Inspect all idlers and pulleys before and after transfer zones.
  • Check for spillage, impact damage, or misalignment due to material drop.
  • Inspect drip pans or collection trays beneath transfer zones.
  • Confirm vibration or impact guards are intact and functioning.

7. Cleaning Systems

• Primary Belt Cleaners
  • Inspect blades for wear, cracking, or missing sections.
  • Check blade-to-belt contact pressure—adjust as per manufacturer spec.
  • Verify that the cleaner is aligned squarely to the belt width.
  • Examine mounting brackets and tensioners for looseness or corrosion.
  • Replace worn or hardened blades promptly to avoid belt damage.

• Secondary Belt Cleaners
  • Inspect contact angle and blade condition (tungsten, polyurethane, etc.).
  • Verify the cleaner is scraping the belt effectively without excessive pressure.
  • Check for blade chatter or vibration during operation.
  • Confirm the tensioning system (spring, air, or mechanical) is functional.
  • Inspect frame and bracket integrity—tighten fasteners as needed.

• Return Side Belt Plows / Scrapers
  • Examine for proper alignment with the belt centerline.
  • Check plow or scraper tips for wear and even contact with the belt.
  • Look for signs of plow bouncing or floating unevenly.
  • Inspect mounting frame and check pivot/hinge function.
  • Remove accumulated material around plow housing.
    

• Brush Cleaners (if installed)
  • Inspect bristle wear and replace brushes if flattened or broken.
  • Check brush rotation and belt contact—adjust motor or tension as necessary.
  • Lubricate brush shaft bearings.
  • Clean trapped fines from brush guard or frame.
    

• Water Spray Systems (if used for cleaning)
  • Inspect spray nozzles for clogging, wear, or misalignment.
  • Verify water pressure is within operating limits.
  • Confirm filters are clean and lines are free of scale or deposits.
  • Check for proper drainage in the spray zone to prevent pooling or slippage.
  • Inspect for water leakage into electrical areas or structural components.

• Cleaner Tensioning Systems
  • Check tensioner mechanism (spring, air, mechanical) for correct preload.
  • Inspect for rust, wear, or deformation of tension springs or cylinders.
  • Verify safety locking or manual retraction functions work during service.
  • Lubricate moving parts as per manufacturer guidelines.
    

• Material Accumulation Zones
  • Clean buildup from under the belt, especially around cleaners and plows.
  • Remove any wet or sticky residue from frames or floor pans.
  • Check if excessive material drop is due to cleaner failure or misalignment.
  • Implement scheduled cleaning for known high-dust or wet zones.

8. Safety Devices and Control Systems

• Emergency Stop (E-Stop) Systems
  • Test each emergency stop switch for immediate belt shutdown.
  • Confirm activation triggers alarms or indicator lights.
  • Inspect pull cord alignment and tension; re-tension if slack is present.
  • Check for wear, cuts, or abrasions on pull cords.
  • Examine switch casings and mounting for damage or looseness.
    

• Belt Misalignment Switches
  • Inspect actuators/arms for free movement and wear.
  • Test function by simulating misalignment—verify belt stops or alarm triggers.
  • Check switch response delay and recalibrate if necessary.
  • Verify housing is sealed and moisture/dust ingress is absent.
  • Clean accumulated dust or debris from pivot areas.
    

• Belt Tear Detectors
  • Inspect sensors for damage, dust, or detachment.
  • Simulate a tear or sensor activation to verify system response.
  • Check wiring for continuity and proper insulation.
  • Confirm the detector is located at proper intervals for maximum coverage.
    

• Speed Monitoring Devices
  • Check speed sensors for accurate readings—compared to manual tachometer.
  • Calibrate sensor if deviation exceeds specified tolerance.
  • Inspect coupling between sensor and shaft for slippage.
  • Clean sensor lenses or surfaces to avoid false readings.
  • Confirm belt stops or alarms when speed drops below safe threshold.
    

• Zero-Speed Switches
  • Test functionality by stopping the belt—verify alarm or shutdown activates.
  • Inspect rotating components connected to the switch shaft.
  • Check for oil or grime that may obstruct detection.
  • Examine mechanical couplings or magnets for breakage or looseness.
    

• Sequence Interlocks
  • Verify interlock logic on the control panel (belt A must start before belt B).
  • Test interlock override and reset functions (manual and automatic).
  • Inspect wiring, PLC outputs, or relay boards for signs of wear or corrosion.
  • Confirm all upstream/downstream equipment interlocks are intact.
    

• Start-Up Alarms and Sirens
  • Test start-up alarm delay (audible and visual) before motor engagement.
  • Confirm sufficient warning time is programmed into the system.
  • Replace worn speakers, horns, or beacons as needed.
  • Clean alarm units to maintain audibility and visibility.
    

• Trip Switches and Safety Relays
  • Inspect for proper installation and no bypass wiring.
  • Test tripping function manually to simulate fault condition.
  • Verify that all trips lead to safe shutdown and isolation.
  • Inspect relay response times and replace aged components.
    

• Control Panel Inspection
  • Open panels and inspect for loose terminals, worn relays, or overheating.
  • Check panel ventilation filters and fans for clogging or failure.
  • Verify indicator lights, HMI screens, and push buttons operate properly.
  • Backup and update PLC logic or HMI settings where applicable.

9. Structural Frame and Support Systems

• Conveyor Frame and Steel Structure
  • Inspect steel framework for visible cracks, rust, corrosion, or fatigue.
  • Tap suspicious areas to detect internal rust or delamination.
  • Check for sagging or warping due to excessive loads or misalignment.
  • Verify structural integrity of welds, joints, and bolted connections.
  • Re-tighten loose bolts and replace corroded hardware.
    

• Walkways, Handrails, and Platforms
  • Check for missing or loose grating panels or anti-slip covers.
  • Inspect handrails and toe boards for structural stability and compliance.
  • Remove material buildup that could cause slips or tripping hazards.
  • Repair bent or damaged stanchions and support brackets.
  • Lubricate hinged platform gates or swing access doors if applicable.
    

• Support Legs, Columns, and Base Plates
  • Inspect base plates for secure anchoring to foundation.
  • Check grout condition and look for cracks or shifting around mounting pads.
  • Examine vertical support members for deformation, corrosion, or pitting.
  • Verify plumb alignment using a level or laser tool.
    

• Cross Bracing and Lateral Stiffeners
  • Inspect cross braces for missing bolts, bending, or rust patches.
  • Check for signs of torsional distortion under dynamic loading.
  • Tighten or replace hardware securing stiffeners and braces.
  • Inspect brace welding seams for signs of cracking or fatigue.
    

• Expansion Joints and Structural Flex Points
  • Verify flexible joints are operating freely with no binding.
  • Inspect rubber, neoprene, or metal bellows for cracks or wear.
  • Ensure joint covers or guards are secure and intact.
  • Examine anchor bolts and sliding plates for proper movement allowance.
    

• Foundation and Ground Anchoring
  • Check for settlement, tilting, or misalignment in foundation pads.
  • Inspect anchor bolts for tension loss or corrosion.
  • Examine soil condition around foundation for water erosion or cracks.
  • Confirm vibration isolators or dampers are functioning and not degraded.
    

• Covers, Guards, and Housing Panels
  • Inspect belt covers and side panels for rust, deformation, or detachment.
  • Check for proper securing of covers—tighten or replace fasteners as needed.
  • Clean under covers to prevent material buildup and pest infestation.
  • Confirm guards comply with safety regulations (distance, height, strength).
    

• Paint, Coatings, and Corrosion Protection
  • Check painted surfaces for bubbling, peeling, or flaking.
  • Touch up exposed metal areas with corrosion-resistant paint.
  • Inspect galvanization or powder-coated layers for damage.
  • Record coating integrity ratings during scheduled assessments.

10. Lubrication Systems and Maintenance Logging

• Lubrication of Bearings and Pulleys
  • Identify all bearings and pulley shafts requiring lubrication.
  • Confirm lubricant type matches manufacturer’s recommendation (grease or oil).
  • Inspect grease fittings (zerk fittings) for damage or clogging.
  • Apply the correct quantity of lubricant to each fitting; avoid over-lubrication.
  • Clean excess grease around bearings to prevent contamination.
  • Schedule lubrication intervals based on operating conditions and load.
    

• Lubrication of Gearboxes and Reducers
  • Check oil levels in gearboxes and replenish if below recommended levels.
  • Inspect oil for contamination or metal particles; replace if needed.
  • Monitor gearbox temperature for abnormal increases during operation.
  • Verify seals and breather valves are intact and functional.
  • Follow OEM schedules for oil change intervals.
    

• Lubrication of Chains and Sprockets (if applicable)
  • Clean chains and sprockets before applying lubricant.
  • Apply chain lubricant evenly along the entire length.
  • Inspect chains for stretch, corrosion, or broken links.
  • Check sprocket teeth for wear or damage and alignment with the chain.
  • Adjust chain tension as required after lubrication.
    

• Lubrication of Slide Rails and Guides
  • Inspect slide rails or wear strips for cleanliness.
  • Apply suitable lubricant or anti-friction coating on guide surfaces.
    
  • Ensure lubricants do not contaminate the belt surface.
  • Monitor guide wear and replace worn sections promptly.
    

• Lubrication System Inspection (Automatic Lubricators)
  • Check operation of automatic lubrication units (timers, pumps, reservoirs).
  • Refill lubricant reservoirs before depletion.
  • Verify delivery lines and nozzles are unobstructed and intact.
  • Inspect control wiring and program settings for correct cycles.
  • Test system alarms or failure indicators.
    

• Maintenance Logging and Documentation
  • Record all maintenance activities in logbooks or digital systems.
  • Include date, time, technician name, and detailed work performed.
  • Document parts replaced, lubricant types and quantities used.
  • Track recurring issues or failures for trend analysis.
  • Schedule preventative maintenance and set reminders.
  • Archive inspection and maintenance reports and photographs where applicable.

What are the Tips to Follow for Conveyor Maintenance?

Under constant use, conveyor systems wear down faster than most realize. To stay on top of conveyor belt maintenance and keep operations steady, follow these maintenance tips:

• Inspect Rollers and Belts Frequently

  Look for signs of wear, cracks, or misalignment in rollers and belts, and replace defective parts immediately to prevent further mechanical strain.

• Clean Accumulated Debris from Tracks and Bearings

  Remove dust, scraps, and grease buildup from all moving parts to maintain proper motion and avoid blockages.

• Check Belt Tension and Alignment Regularly

  Adjust belts to proper tension and alignment to avoid slippage, uneven wear, and added stress on drive components.

• Lubricate Moving Parts at Scheduled Intervals

  Apply manufacturer-recommended lubricants to chains, bearings, and shafts at defined intervals to reduce friction and mechanical resistance.

• Test Emergency Stops and Sensors Without Delay

  Run manual checks on emergency stop functions and sensors to confirm immediate responsiveness and eliminate false triggers.

• Tighten Loose Fasteners and Monitor Support Structures

  Secure bolts, nuts, and structural joints regularly to maintain system stability and prevent vibration-related failures.

To Wrap Up

Organizations that stick to a preventive path with their conveyor system maintenance checklist don’t wait for disruption to force action. They set the pace, protect their uptime, and place fewer demands on emergency response.

Use our free checklist to create a steady rhythm that reduces unexpected breakdowns and thus the downtime which increases equipment longevity. It will offer you an approach to keep the conveyor system reliable and maintain operational continuity, which will ultimately optimize your maintenance efforts.