Solito Solution™  #44

Ball Mill


The mine experienced repeated failures of pumps used on ball mills to circulate lubricating oil. The unscheduled downtime accumulated quickly. Resulting losses of productivity was averaging 12 hours per event six times a year.


Sustainable repairs and revised maintenance procedures returned $1,440,000 of annual production to the mine. Additionally $90,000 of annual maintenance expense was eliminated.

We Found: Six pumps per year were being replaced due to catastrophic failure. The pumps were literally being destroyed from within due to sever particulate contamination in their lubricating oil. The primary culprit was improperly seated filter element seals inside the filter the filter housings.

We Fixed: After the seal was replaced, a seal inspection procedure was developed. The area that housed the crusher’s lubrication equipment was cleaned. This revealed other potential contamination ingress points that were appropriately sealed. A lubrication storage and dispensing facility was added on site.

How We Facilitated Changes: The seal inspection procedure was added to routine PMs. Maintenance technicians were trained in the inspection procedure. All maintenance technicians received training in the proper storage, dispensing, and use of lubricants. Overall awareness of proper lubrication procedures was emphasized throughout the time Solito was on the project.

The numbers: Each failure resulted in at least 8 hours of downtime. The longest failure required 1 week to repair. Production was valued at $30,000/hour.

Returned production to mine:

8 hours X $30,000 = $240,000 of lost production per failure

6 failures/year X $240,000/failure = $1,440,000 annual production returned to the mine

Annual maintenance savings because of unscheduled oil and filter consumption:

$15,000/oil & filter change X 6 changes/year = $90,000 maintenance savings per year