Ball and SAG Mill Liner from BSC

Description

SAG mills and Ball mills are used in mineral processing to grind rocks and ore into a fine slurry to aid the extraction of precious metals.

The mills are massive rotating steel cylinders with steel lifters bolted inside the shell against a flexible liner. SAG Mill liners Ball Mill liners have traditionally been rubber however this becomes damaged and needs to be replaced periodically.

Mills are critical to the process of extracting minerals and the cost of downtime for repairs can be tens of thousands of dollars per hour.

Nukote polyurea is recommended for full relining projects because it works better than rubber and dramatically reduces the shutdown time.

The Challenges

A SAG mill liner is sprayed directly onto the shell of a SAG mill - Western Australia

When the SAG mill liners need to be replaced, using rubber sheets is very time consuming, requiring long, expensive shutdowns.
The slurry is abrasive and wears away steel between the seams in the rubber (called racing). This results in serious damage to the mill shell and the repairs required make future re-lines even slower and more expensive..
The bolts holding the lifters in place often break requiring unscheduled shutdowns.

The BSC SAG Mill Liner Solution

BSC expert teams have lined dozens of mills around the world with fast curing, flexible, and resilient Nukote ST and HTD polyurea ball and SAG mill liners.

The old rubber is removed with ultra high-pressure water jetting. The surfaces are then decontaminated and profiled ready for coating. Nukote HTD polyurea is applied in a single coating, Where the shell steel has been worn away, this can first be filled in with repair material or sprayed with extra polyurea.

The top section of the mill is coated first, then the mill is rotated so the lining can be completed. The charge of balls doesn't need to be fully removed.

The BSC process for mill shell lining can shave days off the time required for traditional rubber lining. Clients report fewer on-ongoing bolt breakages and longer service life.

Key Nukote HTD Physical Properties

Elongation

275% ± 50% at break

Tensile Strength

21.0 ± 1.0 MPa

Hardness

50 ± 5 Shore D

100% solids

0% VOC

Abrasion Resistance

<12mg loss Taber CS 17 wheel 1Kg/1000 rev

For Nukote lining solutions for mining projects,
contact BSC for more information.