Scalping screens protect primary crushers-thus affecting everything thereafter, including minimising recirculation and maximising material value. Mining companies are continually looking for a more efficient way to eliminate fines from entering the primary crusher and reduce wear. For years, vibrating grizzly feeders have widely been used, but that may be about to change. Eccentric screening technology has been making headway for more than 20 years and is proving to offer multiple benefits that far exceed grizzly feeders. W.S. Tyler’s N-Class Eccentric Scalping Vibrating Screens are one example of this technology. Over the past 20 years, more than 225 units have been sold into aggregate and mining applications throughout the world.

This four-bearing vibrating screen features an eccentric shaft assembly technology that offers a unique alternative to grizzly feeders. During every revolution, the eccentricity designed into the shaft forces the screen body upward while the counterbalance weights travel downward. This causes both the force generated by the body and the force generated by the weights to cancel each other out while generating a consistent positive stroke that:

• Minimises structural vibration
• Handles material volume spikes without losing momentum
• Creates a self-cleaning action that minimises plugging and clogging
• Improves overall screening efficiency

Rather than use individual grizzly bars, the N-Class scalps materials with up to 101.6-mmthick perforated plate. This in itself provides another set of benefits:

• Less elongated material falls through the circular perforated plate versus the grizzly feeders screening ‘strips’
• Multiple decks can be easily set up to best separate multiple products
• Circular holes and slightly tapered edges further minimise plugging and clogging
• Easier to switch between opening sizes

W.S. Tyler’s N-Class Eccentric technology is designed to handle heavy-duty applications, yet is flexible enough to fit into most operations that have an apron feeder or the ability to use one. With an incline of 10-20^o, a rubber marshmallow mounting system and heavy-duty frame design, it can take the impact without requiring significant maintenance.

Production          Up to 5,000 t/h

Size Range          From 1.2 m x 2.4 m up to 2.4 m x 7.3 m

Max Particle Size              Up to 203 cm x 101.6 cm

Max Particle Thickness  Up to 101.6 cm

Decks    Up to two

Optional               Electric brake motor for easier stopping