Ball/Pebble mills

This reliable, effective grinding technology dates back more than 200 years, and Metso has since designed, manufactured, and installed more than 8,000 ball/pebble mills, all over the world. Both the ball and pebble mills utilize a tumbling media, ball mills with steel balls, and pebble mills with ceramic or the natural rock itself.

APPLICATIONS
Ball/pebble mills grind ores and other materials to a typical product size of 35 mesh or finer and are suitable in a variety of applications:

Single-stage fine grinding
Regrinding
Second stage in two-stage grinding circuits
Followed by first, second and even third stage crushing
These mills operate in either an open or a closed circuit. Open circuit is best when another stage of grinding follows the mill, reduction ratio is small, and product size control is not critical. Closed circuit is best when size control of the final product is important.

Features
Size range from 5’ x 8’ with 75 HP to 30’ x 41’ and as much as 30,000 HP
Feed Size:
Hard ores: 80% passing 1/4” (6 mm or finer)
Soft ores: 80% passing 1” (25 mm or finer)

Benefits
With more than 100 years of experience in developing this technology, Metso ball/pebble mills ensure the technology is working hard for you. Key benefits include:

Automatic operation, which saves power
Accompanying software to support the most complicated circuits and complex ores

Common flowsheets include:
Open circuit
Closed circuit with hydro cyclones
Closed circuit with vibration screens
Two-stage variations of the above, utilizing two mills in series