A belt failure mid-shift does not announce itself with a warning. It arrives as a burning smell from the drive pulley at 2 a.m., a frayed edge jamming the idler frame, or a cascade of material across the return run — each scenario carrying a cost that compounds by the hour.
These five conveyor belt problems account for the majority of unplanned stoppages in mining, logistics, food processing, and port terminal operations. Each one is preventable. Each one has a defined fix.
Why Conveyor Belt Problems Happen — and Why Early Detection Matters
Industrial conveyor systems run under constant mechanical load — tension cycles, material impact, thermal variation, and pulley flex repeated millions of times across a belt’s service life. Most failures originate from three sources: improper installation, environmental stress, or ageing belt material that has passed its design limits.
Catching these faults early is the difference between a 20-minute idler adjustment and a 6-hour emergency splice. In high-volume distribution centres and bulk mineral terminals, a single hour of downtime runs between £3,000 and £15,000 in lost throughput. Structured conveyor belt maintenance programmes close that gap — permanently.
5 Common Conveyor Belt Problems and How to Fix Them
The following sections detail the most frequent challenges faced by maintenance teams and the specific steps required to resolve them. By using a structured troubleshooting approach, you can maintain the high tensile strength and dimensional precision of your equipment.
Problem 1 — Belt Mistracking: Causes and Correction Steps
Belt mistracking pulls the belt off-centre on the idler frames. The causes: misaligned idler frames, uneven material loading, or a crooked splice introducing camber into the running loop. Uncorrected, edge contact with the conveyor structure destroys the fabric plies within days.
Square the conveyor frame first — any out-of-level frame creates a permanent lateral force. Clear material buildup from pulleys; a 3mm crust of dried ore deflects the belt path. Adjust snub rollers in small increments in the direction of travel. HOLO splicing presses produce camber-free joints by confirming dimensional square before press closure, eliminating.
Problem 2 — Belt Slippage: Causes and How to Address
Conveyor belt slippage occurs when the drive pulley loses grip under load. The signs: burning rubber odour, visible speed lag between pulley and belt, and accelerating lagging wear. Root causes are insufficient tension and lagging worn smooth.
Increase take-up unit tension in measured increments until the belt runs steadily at full load. If tension is correct and slippage continues, replace the lagging. Diamond-pattern rubber or ceramic lagging restores grip on incline conveyors and high-torque bulk aggregate drives where gravity works against the drive system.
Problem 3 — Edge Wear and Fraying: Causes and Prevention
Belt edge wear is always a secondary symptom — it confirms persistent tracking faults have been running uncorrected. Continuous frame contact frays the outer fabric inward, reduces effective belt width, and exposes internal tension members to moisture and contamination. Once tension members are compromised, rated working strength drops sharply.
Install edge sensors that trigger an alarm on first frame contact — before fraying is visible. Correct the tracking fault immediately. HOLO-Cool air-cooled press technology seals trimmed edges cleanly during repair splices, preventing unravelling from the cut surface.
Problem 4 — Belt Surface Cracking: When to Repair and When to Replace
Belt surface cracking develops from UV exposure on outdoor conveyors, sustained heat above the belt’s temperature rating, or simple ageing. Cover cracks allow moisture and abrasive fines to penetrate the carcass, triggering internal delamination invisible from the surface.
Replace the section when cracks reach the fabric plies or the cover feels brittle under flex testing. HOLO PA series air-cooled presses splice replacement sections into the running loop, restoring up to 90% tensile strength. Section replacement is more cost-effective than full belt replacement on conveyors exceeding 200 metres with isolated damage zones.
Problem 5 — Material Spillage and Carryback: Causes and Solutions
Spillage drops material in transit from off-centre loading or failed skirting. Carryback sticks to the belt past the discharge point, accumulating on return idlers and creating slip hazards below the conveyor. Both issues cause premature wear and create safety non-compliance.
Install primary scrapers at the head pulley discharge point and secondary scrapers 300–500mm downstream. Adjust the loading chute to land material centrally within the troughed belt profile. Weekly inspection of the return area catches carryback buildup before it compacts into idler-damaging deposits.
Quick-Reference: 5 Conveyor Belt Problems at a Glance
The table below maps each problem to its primary symptom, root cause, HOLO solution, and recommended detection method.
| Problem | Symptom | Root Cause | HOLO Solution | Detection Method |
| Mistracking | Belt wandering off-centre | Misaligned idlers / crooked splice | HOLO press: camber-free splice | Weekly visual audit |
| Slippage | Drive pulley spinning freely | Low tension / worn lagging | Adjust take-up/diamond lagging | Burn smell/lag test |
| Edge Wear | Fraying outer fabric layers | Frame contact from persistent tracking | HOLO-Cool air press edge seal | Edge sensor / tracker switch |
| Surface Cracking | Brittle, cracked cover | UV / heat / natural aging | HOLO PA series section splice | Infrared thermography |
| Spillage / Carryback | Material on floor/frame | Poor loading / worn scrapers | Primary & secondary scrapers | Return-area inspection |
Preventive Maintenance: What to Check and When
Weekly Inspection Tasks
• Walk the full conveyor length performing a visual belt tracking audit — do not spot-check.
• Clear pulley surface buildup above 5mm; check for abnormal bearing noise at tail, head, and snub pulleys.
• Confirm all safety guards and emergency stop cords are operational before each shift.
Monthly Inspection Tasks
• Measure belt thickness at 5 points across the full width to identify uneven wear patterns.
• Inspect all splice joints for delamination or surface cracking. A HOLO belt splicing machine produces the joint geometry that holds across 1,000,000+ flex cycles.
• Run infrared thermography on motors and gearboxes under full load; calibrate take-up tension against manufacturer specifications.
How Do I Fix a Conveyor Belt That Keeps Wandering to One Side?
Clean all pulleys and idlers first — material buildup is the most common cause of persistent belt wander. Level the conveyor frame; any out-of-square frame introduces a continuous lateral force.
Adjust idler sets in the direction of belt travel in small increments until the belt centres. A camber-free splice produced on a HOLO splicing press eliminates the most common joint-related tracking cause at installation.
Upgrade Your Belt Maintenance Capabilities with HOLO
Unplanned stoppages from belt mistracking, slippage, or splice failure are preventable — provided the right equipment backs the maintenance programme.
HOLO engineers belt fabrication machinery for facilities that cannot afford extended downtime: air-cooled and water-cooled splicing presses, precision hot-press systems, and field splicing toolkits producing consistent, camber-free joints on every repair.
Visit HOLO Belt Splicing Machines to explore the full equipment range. Contact our technical team for a solution specification matched to your belt type, environment, and production volume.
• OLED Touchscreen: Multi-language, real-time data, remote monitoring.
• 8-Min Heat-Press Cycle: Fast heating → holding → cooling, consistent joints.
• Mobile APP Control: Monitor, save data, alerts.
Frequently Asked Questions
How often should conveyor belt splices be inspected?
Inspect splices weekly on all conveyors. On 24/7 high-cycle systems — food processing lines, automated distribution centres, and mineral terminals — inspect every 7 operating days. Visible delamination, surface cracking at the joint, or fastener movement requires immediate repair before the next full-load shift.
What causes persistent belt slippage even after tension adjustment?
Pulley lagging failure. Smooth or contaminated lagging cannot generate sufficient friction against the belt’s inner surface under load. Replacing worn lagging with a diamond-pattern or ceramic surface resolves slippage on bulk material drives, incline conveyors, and high-tonnage applications where torque demands exceed standard rubber lagging capacity.
When should a cracked belt be replaced rather than spliced?
Replace when cracks reach the fabric plies — test with a feeler gauge. Surface cracks confined to the cover compound are repairable by section splice on a HOLO PA series press. Full replacement is required when carcass delamination is present, tensile strength falls below 70% of rated capacity, or the belt has exceeded its design service life.