Mood, Industries, 1600x230


A quarrying company was experiencing short service life on its conveyor tail drum take-up unit. Located in an inaccessible area beneath a shaker screen, the unit´s bearings were subjected to particularly arduous conditions due to elements in the environment. This situation was compounded by the fact that regular re-greasing was a difficult task due to the remote bearing location. This lead to regular bearing failure and costly conveyor downtime. NSK analyzed the bearing application and determined that water and grit were entering the bearings and causing failure. A trial was suggested using RHP Self-Lube® with Triple Lip Seals. This solution extended the service life from 4 months to over 1 year.

Quarry, Mining , Construction, conveyor tail drum assembly
  • Quarry conveyor tail drum assembly
RHP Self-Lube, Bearing Unit, Protector, cut, 874x555
  • Self-Lube® with triple lip seal bearing insert

Key Facts

  • Quarry conveyor tail drum
  • Highly abrasive conditions including water and grit
  • Failure of the bearing resulted in seizure and conveyor downtime with consequential loss of production
  • NSK solution: Self-Lube® housing with triple lip seal bearing inserts designed for high impact and heavily contaminated environments
  • Increased life-time resulting in reduced downtime and improved efficiency

Value Proposals

  • Failed Bearing Analysis showing route cause as ingress of water and grit
  • Application assessment showed highly abrasive conditions
  • Trial of RHP Triple lip seal Self-Lube® bearings showed increase in life
  • Best practice from re-lubrication applied
  • Technical support provided for improved bearing performance

Product Features

  • Three high integrity nitrile seal lips with lubrication traps to stop ingress of contaminates
  • High strength steel outer case resists impact to seal and provides a primary dust trap
  • Available for both setscrew and eccentric locking collar insert options
  • Large size range offered, including imperial options
  • Inserts interchangeable with standard items
  • Longer bearing life through superior seal performance
  • Extended re-lubrication intervals, greatly reducing maintenance costs and increased productivity of machinery
  • Simple implementation; ready replacement for existing bearing units
  • Mounting on the shaft with balled setscrew, providing much greater resistance to loosening
Cost Saving Breakdown
Before Cost p.a. NSK Solution Cost p.a.
Bearing Costs: Old bearings per conveyor $186 Bearing Costs: New bearings $67
Engineering Costs: Bearing life: 4 months
3 hours loss of production on failure @ $1,028/h (3 per year)
$9,252 Engineering Costs: Bearing life: Ongoing
No loss of production since build
Costs of lost production: Maintenance costs: 3 x $73/h (3 per year) $660 Costs of lost production: Maintenance costs (original build) $220
Total Costs $10,096 $3,369