The Steep Angle Problem
Conveyor belts become impractical at steep angles. Standard flat belts max out at around 18β20Β° for most materials. Chevron (cleated) belts extend this to 30β38Β°. But some applications need steeper angles still β 45Β°, 60Β°, even 90Β° vertical lift. For these, a different belt type is needed.
Sidewall conveyor belts β also called corrugated sidewall belts or steep incline belts β can convey materials at angles up to 90Β°.
How Sidewall Belts Work
A sidewall belt has three components:
Base belt: A standard EP belt carcass with carrying-side cover.
Corrugated sidewalls: Flexible corrugated rubber walls bonded to both edges of the base belt, extending upward. These walls retain material on the belt at steep angles, preventing lateral spillage.
Cross cleats (T-cleats or C-cleats): Rubber cleats bonded across the carrying surface at regular intervals (typically every 300β600mm). These act as shelves that support the material weight on steep inclines, preventing the load from sliding backward.
The combination of side containment and cross-cleat support means material can be carried at virtually any angle, including vertical.
Comparison: Sidewall Belt vs Chevron Belt vs Flat Belt
| Property | Flat Belt | Chevron Belt | Sidewall Belt |
|---|---|---|---|
| Maximum incline angle | 18β20Β° | 28β38Β° | Up to 90Β° |
| Material containment | Belt edges only | Belt edges + cleat faces | Enclosed by sidewalls |
| Capacity | High | Moderate | Lower (cross-cleat pockets) |
| Material particle size | Unlimited | Limited by cleat height | Limited by cross-cleat spacing and sidewall height |
| Belt cleaning | Easy | Difficult | Very difficult |
| Cost | Lowest | Moderate | Highest |
| Complexity | Simple | Moderate | High |
| Maintenance | Easy | Moderate | More demanding |
| Noise | Standard | Standard | Standard |
| Length of inclined section | Unlimited | Unlimited | Typically shorter runs |
When Sidewall Belts Make Sense
When angle exceeds 38Β°. This is the primary reason to specify a sidewall belt. If your terrain requires a steeper angle than chevron can achieve, sidewall is the solution.
Space-constrained installations. A sidewall belt can replace multiple transfer conveyors and intermediate hoppers. A single steep sidewall conveyor from ground level to a stockpile top can replace a ground-level conveyor + incline conveyor + transfer point sequence. This reduces footprint, dust emission points, and maintenance locations.
Underground development inclines. Some underground mine configurations use very steep incline conveyors where space for a longer shallower angle is not available. Sidewall belts are used in these situations.
Small to medium capacity applications. Sidewall belts are not typically used for high-tonnage main haulage. They're suited to feed conveyors, secondary conveyors, and material distribution β typically up to 500β1,000 t/h depending on belt width and cross-cleat size.
Limitations of Sidewall Belts
Cannot be cleaned effectively. The corrugated sidewalls and cross cleats make standard belt scrapers impractical. Material adheres in the pockets between cleats and is difficult to remove. Carryback can be significant. This is the most important operational limitation to plan for.
Return run complexity. The sidewalls and cleats must flatten out on the return run. This requires carefully designed transition sections and return rollers that accommodate the sidewall profiles. The belt must not be over-bent at transitions or the sidewalls crack.
Limited material size. Cross-cleat pocket dimensions limit maximum material size. Very coarse ore (over 150β200mm top size) doesn't suit standard sidewall configurations.
Higher cost and maintenance. Sidewall joints, cleat attachments, and sidewall material are all wear items that require periodic inspection and replacement. Maintenance is more involved than a standard flat belt.
Not reversible. Like chevron belts, sidewall belts only work in one direction.
Key Specification Parameters
When specifying a sidewall belt, the following parameters define the system:
- Belt width: The base belt width (e.g., 650mm, 800mm, 1000mm)
- Sidewall height: How tall the corrugated sidewall extends above the base belt surface (e.g., 120mm, 160mm, 200mm, 315mm) β determines material volume per pocket
- Cross-cleat type: T-cleat (standard) or C-cleat (for finer materials that would pass under a T-cleat)
- Cross-cleat spacing: Typically 300β600mm β affects capacity and maximum lump size
- EP rating: The base belt tension rating for the conveyor length and lift height
- Conveying angle: Up to 90Β° β affects capacity calculation
Frequently Asked Questions
We need to convey crushed aggregate at 60Β°. Is sidewall belt the right choice? Yes, if the aggregate top size suits your chosen cross-cleat pocket dimensions. Provide us with your material top size, required capacity (t/h), conveyor length, lift height, and angle and we'll specify the appropriate configuration.
How do sidewall belts handle on the return run? The belt must transition smoothly from the loaded incline configuration back to flat for the return run. This requires well-designed transition sections. Belt bending radius at transitions must not exceed the minimum recommended for the sidewall height selected.
Do you supply sidewall belts as complete systems or just the belt? We supply the sidewall belt itself. The complete conveyor system including structure, drives, and idlers is typically engineered and supplied by a conveyor system integrator who specifies our belt.
Contact Elephant Rubber
We manufacture sidewall conveyor belts in a range of widths, sidewall heights, and EP ratings. Contact us with your application parameters for a specification and quote.