Mood, Industries, 1600x230


A mining and metal company was experiencing repeated failures on their fully mechanized bolting jumbo. Bearings were being exposed to water and abrasive particles. Short life of only two months was realized in their deep groove ball bearings used in the gear mechanism of bolter. NSK assessed the situation and found hard contaminants were entering the bearing causing failure. A trial with  NSK Molded-Oil bearings was proposed which resulted in an immediate improvement with 3x's longer life for both the bearings and machine gears.

Quarry, Mining , Construction, bolter, Sandwik
  • Fully mechanised bolting jumbo machine
Molded-Oil, Spacea, Comp
  • Deep Groove Ball Bearings with Molded-Oil

Key Facts

  • Special bolter machine working underground
  • Harsh environment with exposer to water and abrasive particles
  • 3 machines experiencing frequent bearing failures every 2 months
  • Premature gear wear due to bearing failures
  • High cost due to changing of gears
  • NSK solution: Molded-Oil bearings increasing bearing life from 2 to 6 months
  • Cost saving realized due to increase in gear changing period

Value Proposals

  • After a few site visits, customer requested a solution in order to increase the life time of the bearing
  • Application assessment and Failure Analysis indicated highly abrasive conditions like water and hard particle Ingress negatively impacting the lubrication
  • A trial was proposed using NSK Molded-Oil Deep Groove Ball Bearings which proved to be successful -extending  bearing life by 3x's
  • Molded-Oil bearings were fitted to all 3 machines resulting in a reduction in machine down time and an extension in gear changing period

Product Features

  • Stainless steel for corrosive environments
  • Molded-Oil provides continuous supply of lubrication oil
  • Grease-free property with no oil refilling keeps operating environments clean
  • Operating life more than twice as long as grease lubrication, in water or dust contaminated environments
  • Contact-seal type available in standard inventory for ball bearings
  • Achieves extended maintenance-free performance with continuous supply of lubricant
  • Available for high speed applications
  • Available in ball bearing, spherical roller bearing and tapered roller bearings
Cost Saving Breakdown
Before Cost p.a. NSK Solution Cost p.a.
Bearing Costs: Bearing costs:
- Deep Groove Ball Bearings replaced 6 times per year
$128 Bearing Costs: Molded-Oil Deep Groove Ball Bearings, replaced twice a year $385
Engineering Costs: 6 replacements/year x 3 machines x Manpower x $27/h $1,446 Engineering Costs: 2 replacements/year x 3 machines x Manpower x $27/h $482
Engineering Costs: Gear failure costs:
- Gear cost x 3 machines x 6 times/year
$19,284 Engineering Costs: Gear failure costs:
- Gear cost x 3 machines x 2 times/year
Total Costs $20,858 $7,295