The Core Difference
EP belts use a carcass woven from polyester (E) and nylon (P) fabric plies. Steel cord belts use parallel steel wire ropes as the tensile member. This difference in carcass construction drives differences in strength, stretch, weight, splice method, and cost.
Neither type is universally better. The right choice depends on your conveyor length, tension requirements, lift height, and budget.
Side-by-Side Comparison
| Property | EP Fabric Belt | Steel Cord Belt |
|---|---|---|
| Tensile strength range | EP100βEP630 (kN/m) | ST630βST5000+ (kN/m) |
| Elongation at working load | 1.5β2.0% | 0.1β0.25% |
| Typical application | Up to ~500m conveyor length | 500m to 10km+ overland |
| Splice method | Mechanical fasteners or vulcanized step splice | Steel cord vulcanized splice only |
| Splice difficulty | Moderate β step splice doable on-site | High β requires trained splicing crew and equipment |
| Weight | Lighter | Heavier (steel adds significant weight) |
| Impact resistance | Good β fabric absorbs impact | Lower β steel cords can be damaged by sharp impact |
| Cost per meter | Lower | Significantly higher |
| Minimum pulley diameter | Smaller | Larger (steel cords require larger bend radius) |
| Typical service life | 3β7 years depending on application | 5β15 years on long-distance systems |
| Repair on-site | Easier β patches possible | More difficult β cord damage requires proper repair |
When to Use EP Belts
EP belts are the right choice for the majority of conveyor applications:
Conveyor length under 400β500 meters. At these lengths, the stretch characteristics of EP belts are manageable and steel cord's low-elongation advantage doesn't justify the cost difference.
In-plant and secondary conveyors. Crushers, screens, plant feed conveyors, and stackers typically use EP belts regardless of the overall mine scale.
Applications with impact loading. At primary crusher discharge and ore receiving hoppers, EP fabric absorbs impact better than rigid steel cords. An EP belt with good cover and impact bars underneath is often the right choice even on large mines.
Where on-site splicing skills are limited. Step splicing EP belts is a skill that most conveyor maintenance crews can learn. Steel cord splice requires specialist training and press equipment.
Budget-constrained operations. EP belts cost substantially less per meter. For a 200m conveyor, the difference may be significant enough to influence the decision even if steel cord would technically work.
When to Use Steel Cord Belts
Steel cord becomes the appropriate choice in specific situations:
Long overland conveyors (500m+). On a 3km overland conveyor, EP belt stretch would require very long take-up travel or frequent re-tensioning. Steel cord's 0.1β0.25% elongation makes tension management practical at these distances.
High-lift applications. Steep conveyors lifting material significant vertical distances need precise tension control. Steel cord's low stretch helps.
High-tension systems. When calculated belt tension exceeds EP belt capacity (roughly above EP630), steel cord is the engineered solution.
Long design life priority. On a conveyor where downtime is extremely costly and access for belt change is difficult (deep underground main haulage, remote overland), steel cord's longer service life can justify the premium.
Common Mistakes
Over-specifying steel cord for short conveyors. We occasionally see inquiries for steel cord belts on 150m in-pit conveyors. Unless there's a specific tension calculation driving this, EP is the practical and economical choice.
Under-specifying EP rating. Choosing EP150 for an application that needs EP315 to handle the load and impact causes premature carcass failure. The EP rating should come from proper belt selection calculation, not cost-cutting.
Ignoring splice requirements when specifying steel cord. If your maintenance crew hasn't been trained in steel cord splicing and you don't have the press equipment, a steel cord belt on a remote site is a problem waiting to happen.
Frequently Asked Questions
Can I replace a steel cord belt with an EP belt on the same conveyor? Sometimes, but it requires recalculating take-up requirements and checking pulley diameters. Steel cord and EP belts have different minimum pulley diameter requirements. A conveyor designed around steel cord may need modifications to run EP. Consult your conveyor engineer before switching.
What is the strongest EP belt available? Standard production runs to EP630. Some manufacturers produce EP800 and EP1000 for specific applications. Beyond that, steel cord is the standard engineering solution.
Do steel cord belts need different idlers? The idlers themselves are not fundamentally different, but steel cord belts are heavier, which affects idler load calculations. Belt sag is also lower with steel cord due to lower stretch, which can affect idler spacing design.
What tensile strength does my application need? This requires a belt selection calculation based on conveyor length, lift, belt width, material density, speed, and loading conditions. Contact us with your conveyor data sheet and we can assist with specification.
Contact Elephant Rubber
We manufacture both EP and steel cord conveyor belts. If you have conveyor specifications and need help selecting the right type and rating, send us the details.