Full definition
Abrasion-resistant rubber is a specialized formulation primarily based on natural rubber (NR) or NR blends designed to endure wear and tear caused by abrasive materials in mining applications. This rubber is engineered to provide exceptional resistance to mineral particle impact, making it suitable for environments such as chutes, hoppers, cyclones, pipes, and mills where abrasive materials are present. The formulation typically features high-quality NR polymer, which exhibits strain-crystallizing properties that enhance its impact resilience. The hardness of these compounds usually ranges from 35 to 65 Shore A, with softer compounds providing better energy absorption during impacts — a significant advantage of NR over harder materials like steel. The incorporation of high carbon black loading, such as N330 or N220, significantly increases the abrasion resistance, improving the longevity and performance of the rubber in harsh conditions.
The thickness of abrasion-resistant rubber sheets or linings can vary between 6 to 50 mm, depending on the severity of the wear and the expected replacement interval. For premium grades, the abrasion loss is maintained below 120 mm³ as per DIN 53516, while ultra-premium grades can achieve losses lower than 80 mm³. In terms of performance, NR outperforms styrene-butadiene rubber (SBR) by 2-3 times and steel by 5-10 times when it comes to impact and gouging abrasion caused by large particles impacting at angles greater than 45°. This resilience is due to the rubber's ability to absorb and elastically return energy rather than undergoing plastic deformation or fracture, which can be critical in mining operations.
However, there are limitations to consider. Abrasion-resistant rubber exhibits poor resistance to oils and is less effective against sharp-angle sliding abrasions (less than 15°), where alternatives like steel or ceramics may provide superior protection. Common applications for this rubber include linings for chutes and hoppers, cyclone feeds and overflows, pipe elbows, mill discharge boxes, and conveyor loading zones. It is available in various forms, such as sheets for adhesive bonding, pre-molded wear tiles, and rubber-backed ceramic composite tiles, which can offer enhanced performance in specific applications. The performance and classification of abrasion-resistant rubber are guided by the ISO 14890 standard and tested according to DIN 53516, ensuring quality and reliability in demanding industrial environments.