The Problem Chevron Belts Solve
On inclined conveyors, material slides backward down the belt if the incline angle exceeds what friction alone can hold. The maximum angle a flat belt can convey depends on the material β dry gravel might hold to 18Β°, wet coal to 12Β°, smooth round aggregate to 10Β°. Beyond these angles, material rolls back, causing spillage and uneven feed.
Chevron (also called cleated or profiled) belts add molded rubber profiles to the carrying surface that prevent material rollback, allowing steeper conveying angles β typically 25β40Β° depending on the chevron height and material.
How Chevron Belts Work
Chevron profiles are V-shaped or U-shaped ridges molded into the belt's top cover. Material sits in the pockets between cleats and is carried up the incline by the cleat face rather than relying solely on friction.
Standard chevron heights: - 15mm β for fine materials, moderate inclines to 25Β° - 20mm β general purpose, inclines to 30Β° - 25mm β coarser materials, steeper inclines to 35Β° - 32mm β large lump materials, inclines to 40Β°
The cleat height must suit the material particle size β cleats too short for the material size don't prevent rollback; cleats too tall for fine material cause material to avalanche over the cleats.
Side-by-Side Comparison
| Property | Flat Belt | Chevron Belt |
|---|---|---|
| Maximum conveying angle | ~18β20Β° (material dependent) | 25β40Β° (cleat height dependent) |
| Suitable for horizontal/gentle incline | Yes β preferred | Works but adds unnecessary cost |
| Material particle size flexibility | All sizes | Must match cleat height to material size |
| Belt cleaning | Easy β scrapers contact full surface | Difficult β scrapers cannot contact cleat faces |
| Return idler compatibility | Standard | Requires flat return idlers (no trough) |
| Reversible operation | Yes | No β cleats only work in one direction |
| Belt splicing | Standard step splice | Same, but splice area has no cleats β temporary capacity reduction at splice |
| Cost | Lower | Higher β molded profiles add to manufacturing cost |
| Cover wear | Even across width | Cleat faces wear; re-profiling not practical |
When to Use a Flat Belt
Inclines below 18Β°. Flat belts handle this range well for most materials. Adding chevron profiles adds cost with no functional benefit.
When belt cleaning is critical. Scrapers work effectively on flat belt surfaces. Chevron belts cannot be cleaned properly with standard scrapers β carryback increases on the return run.
Reversible conveyors. If the conveyor needs to run in both directions, chevron belts don't work β the cleats only prevent rollback in one direction. Flat belt with friction or reduced load is the only option.
Fine, sticky materials. Sticky materials (wet clay, wet coal fines) pack between chevron cleats and become difficult to discharge cleanly at the head end. Flat belt with proper discharge assistance (plows, scrapers) often works better.
Long, high-tonnage conveyors. Chevron belts have lower capacity than flat belts at the same width because cleats reduce the usable cross-section. For high-throughput systems, flat belt with a shallower incline (achieved by longer conveyor length) is usually preferred.
When to Use a Chevron Belt
Inclines of 18β40Β°. This is where chevron belts are necessary. If your terrain requires a steep incline and a longer flat belt is not practical, chevron is the solution.
Mobile and portable equipment. Tracked mobile crushers, portable stockpiling conveyors, and mobile screening plants often use steep inclines to minimize footprint. Chevron belts are standard on this equipment.
Underground incline conveyors. Space constraints in underground mines often require steep angles. Chevron belts are common on development heading and decline conveyors.
Loose, free-flowing materials. Grain, fertilizer, sand, gravel, and similar materials slide back easily on inclines. Chevron belts are standard for these materials even at moderate inclines of 20β25Β°.
Short inclines. If the inclined section is short and installing a longer flatter conveyor would require significant civil works, a short steep chevron conveyor is often the practical solution.
Limitations of Chevron Belts
Cannot use standard belt cleaning. This is the most significant operational limitation. The cleat faces and the spaces between cleats cannot be reached by standard scrapers. Carryback is higher with chevron belts. In applications where carryback is a significant problem, this is a real consideration.
Material discharge requires attention. At the head end, material must clear the cleats cleanly. Some materials bridge across cleats and don't discharge properly. A plow or deflector may be needed.
Cleat wear is the belt's wear-out mechanism. Once cleats wear below effective height, the belt loses its anti-rollback function. There is no practical way to restore worn cleats in the field.
Not suitable for troughed return. Chevron belts return flat β the cleats prevent the belt from being troughed on return idlers. This means the return run must be supported on flat return idlers, which are less common than troughed sets.
Frequently Asked Questions
What cleat height do I need for my material? As a general guide: cleat height should be approximately 1/3 to 1/2 of the maximum particle size, and at minimum 1.5Γ the material's tendency to roll. For fine materials (under 20mm), 15β20mm cleats are typical. For coarse materials (20β100mm), 25β32mm cleats. For very coarse lump material over 100mm, chevron belts become less effective and pipe belts or bucket elevators may be more appropriate.
Can I put a scraper on a chevron belt? Standard belt scrapers contact the flat carrying surface and cannot clean between cleats. Some operations use a rotating brush cleaner or a water wash system on chevron belts, but neither is as effective as scraper cleaning on a flat belt. If carryback is a concern, factor this into your decision.
What's the maximum angle achievable with chevron belts? In practice, 35β38Β° is achievable with tall cleats (32mm) and suitable material. Beyond 40Β°, pipe belts, bucket elevators, or skip hoists are more appropriate solutions.
Contact Elephant Rubber
We supply chevron conveyor belts in 15mm, 20mm, 25mm, and 32mm cleat heights in a range of EP constructions. Contact us with your incline angle, material type, particle size, and belt width requirement.