Typical elements of belt construction.
Typical elements of belt construction.
Details of typical belt construction using Kevlar fiber.
Details of typical belt construction using Kevlar fiber.

DuPont Protection Technologies recently announced that the inclusion of its Kevlar material in mining conveyor belts has demonstrated increased productivity and reduced annual maintenance costs. Data collected in a field trial hosted by Chilean copper producer Codelco’s Andina Division, said DuPont, demonstrated a capacity increase of more than 18%, with a 60% reduction in annual maintenance costs.

In the test, Andina replaced a 48-m-long conveyor belt containing a 5-ply conventional nylon/polyester (EP) cord carcass with a comparable belt containing a single-layer DuPont Kevlar

Advanced Performance (AP) fiber. DuPont said throughput increased 3,000 t/d, while required belt maintenance time fell significantly and yearly maintenance costs dropped from $0.14/t to $0.05/t.

“The lightweight strength, durability and performance of this advanced material in extreme conditions make it an ideal choice in this application,” said William F. Weber, vice-president, Kevlar, DuPont Protection Technologies. “The belts can run faster with less wear and tear, enabling mining companies to break boundaries—to ‘Dare Bigger’ in terms of their capacity.” (Dare Bigger, according to the company, is the new brand platform for DuPont Kevlar.)

DuPont said Kevlar fiber enables conveyor belt manufacturers to offer lighter, more flexible, and longer life solutions to mining applications, increasing throughput and reducing operational costs associated with installation, maintenance, replacement and energy consumption. Claimed advantages include:

  • Ease of installation—Belts made with Kevlar fiber are easy to integrate into an existing setup because, unlike polyester/nylon or steel, belts made with Kevlar can go on almost any size pulley or system without reconfiguration.
  • Productivity improvements—Belts made with Kevlar fiber are lighter and can run at higher speeds, are stronger and therefore help reduce maintenance downtime, and are more flexible so they allow a greater trough angle preventing materials from sliding off, even at higher speeds.
  • Energy savings—Kevlar can provide cost savings in terms of decreased
  • power consumption. DuPont has developed an energy calculator to help belt manufacturers and mining companies evaluate the benefits of adding Kevlar fiber for lower energy per ton of material conveyed.
  • Reduced maintenance—Despite their flexibility, belts made of Kevlar fiber exhibit very low creep. Since they hardly stretch, once installed, belts containing Kevlar rarely require re-splicing, a process that typically consumes a whole day. This stability helps reduce maintenance outages.