ABRASIVENESS RATING

Abrasiveness rating is the qualitative scale that describes how rapidly a given bulk material wears the belt cover, idler shell and chute lining surfaces it contacts. Unlike bulk density or angle of repose, abrasiveness is not a single measurable number; it is a category — Low / Medium / High / Very High — based on field experience, supplemented by quantitative tests such as the DIN abrasion loss (mm³ on a standard rubber wheel) for cover compounds and the Bond Abrasion Index for mining ores.

Typical classifications: Low — grain, dry coal, wood chips, paper trim; Medium — wet coal, cement, limestone, salt; High — quarry stone, iron ore, sinter, glass cullet; Very High — silica sand, taconite, alumina, ferro-silicon, fused magnesia. Selection of [cover compound](/glossary/cover-compound) grade follows directly: Low/Medium materials run on Grade L or general-purpose covers; High abrasiveness needs Grade D or Grade H covers; Very High demands the toughest cut-and-gouge cover compounds plus thicker top covers (often 10–20 mm instead of the more typical 5–8 mm).

Idler choice also tracks abrasiveness. Standard steel-shell rolls handle Low to Medium duty; [ceramic-lagged](/products/ceramic-lagged-idler) shells are common for High abrasiveness mining duty; [stainless-steel](/products/stainless-steel-idler) shells serve corrosive-plus-abrasive duty (fertilizer, salt, marine). The Bulk Material Properties tool tabulates an abrasiveness rating against every listed material so designers can quickly cross-reference cover and idler specs against the cargo class.