How to Fix Conveyor Belt Mistracking

Conveyor belt mistracking is caused by uneven loading, misaligned idlers, worn pulleys or crooked splices. Fix it by centering the load, aligning idlers, installing self-aligning training idlers, and checking pulley alignment.

Case Study: Rubber Chute Liners Reduce Primary Crusher Downtime at a Chilean Copper Mine

Background

A copper mine in the Atacama Region of Chile was experiencing high maintenance frequency on the primary crusher feed chute. The chute received run-of-mine copper porphyry ore directly from the shovel/truck cycle, with lump sizes up to 600mm and drop heights of approximately 2.5 meters.

The original chute was lined with 20mm manganese steel wear plates. Maintenance records showed liner replacement was required every 6–8 weeks on the impact zones — each change required a half-shift crusher shutdown and two maintenance crew.

Assessment

The primary wear mode was impact and gouging at the initial impact area, transitioning to sliding abrasion lower down the chute walls. Both mechanisms were present, but impact dominated at the top.

Natural rubber (NR) liners were proposed for the impact zones. NR at 50–55 Shore A absorbs impact energy elastically — rubber deforms and springs back rather than being gouged away. For the lower chute walls where ore slides rather than impacts, a higher-hardness SBR compound (65 Shore A) was proposed for better sliding abrasion resistance.

Cover thickness was increased from 20mm steel to 60mm rubber on the impact face.

Installation

Panels were manufactured as bolt-on pieces fitting the existing chute bolt pattern — no structural modification needed. Installation completed in a planned 4-hour window. The rubber panels weighed approximately 1/6 of the steel plates they replaced, simplifying handling.

Results

The rubber liners ran 22 weeks before first inspection. Impact zone panels showed approximately 40% wear — estimated total life 32–34 weeks. Steel liner life had been 6–8 weeks.

Approximate improvement: 4–5× longer liner life.

Secondary benefit: measurable noise reduction in the crusher feed area — rubber-lined chutes are substantially quieter than steel when receiving hard rock impact.

Annual shutdown comparison: - Steel liners: 7–8 liner change shutdowns per year - Rubber liners: approximately 1–2 shutdowns per year - Net saving: approximately 6 fewer half-shift shutdowns annually

Key Lessons

Match liner material to wear mechanism. Steel resists sliding abrasion well but is poor at absorbing repeated high-energy impact. A primary crusher feed chute at 2.5m drop height is an impact application — rubber is the right material for the impact zones.

Thickness matters in impact applications. 60mm rubber performs substantially better than 20mm rubber because the additional thickness provides more energy-absorbing mass and more wear material before replacement.

Elephant Rubber supplied the rubber chute liner panels for this project.