NSK Case Study


Air Recirculation Fan

Cost Savings: $415,546

A customer was experiencing bearing failure on an Air Recirculation Fan application within an ore preparation plant. This had been a regular problem. Compressed air cooling was applied to try and reduce the bearings’ high running temperature. NSK Engineers conducted an Application Review including a temperature survey of the fan and bearings, revealing major issues with incorrect fitting of the bearings, over-lubrication and inadequate sealing arrangement. NSK recommended using NSKHPS Spherical Roller Bearings within NSK SNN Pillow Blocks and NSK Labyrinth seals. In addition, recommendations were given for correct fitting and correct lubrication intervals and amounts. A trial was conducted resulting in no bearing failure for more than 12 months. The compressed air cooling was also removed, adding additional savings.

Key Facts

Air recirculation fan application
High bearing temperatures in operation
Extraordinary measures – compressed air – required to countermeasure temperature rise
Incorrect fitting, lubrication amounts and frequencies

Air Recirculation Fan

Value Proposals

NSK engineering conducted an Application Review including a Temperature Survey and a Bearing Condition Report
NSK engineers recommended NSKHPS Spherical Roller Bearings in combination with SNN Pillow Blocks and Labyrinth seals and suggested changes in the lubrication amounts and intervals
Trial conducted, with NSK Engineering overseeing the installation and implementation of NSK recommendations
The customer benefited from increased productivity, reduced maintenance costs and the removal of compressed air resulting in a significant cost savings

Product Features

Manufactured from grade 200 cast iron
High precision bore for optimum bearing seating
Split block design allows for easy mounting and dismounting of pre-assembled shafts
Available for shaft diameters from 20 to 140 mm and/or 3/4” to 5 1/2”
Threaded lubrication hole(s) on the cap and 1 drainage outlet on the base
Dimples on the housing surface facilitate additional holes for sensors, lubrication, mounting bolts or locating pins
Large oil bath to maximize oil change intervals
Good heat transfer
Contact and non-contact seal options
SNN Pillow Block and
NSKHPS Spherical Roller Bearing

Cost-Savings Breakdown

  Before Cost NSK Solution Cost  
  $9,002/hour x 36 hours downtime due to bearing failure $324,072 No downtime $0  
  $45/hr x 36 hours x 2 persons due to bearing failure $3,240 Manpower, fitting of NSK bearing $45/hr x 8 hours x 2 persons $720  
  Compressed air $88,954 Removal of compressed air $0  
  Bearing $804 Bearing $804  
  Total Costs $417,070 Total Costs $1,524  
Before Cost
$9,002/hour x 36 hours downtime due to bearing failure $324,072
$45/hr x 36 hours x 2 persons due to bearing failure $3,240
Compressed air $88,954
Bearing $804
Total Costs $417,070
NSK Solution Cost
No downtime
Manpower, fitting of NSK bearing $45/hr x 8 hours x 2 persons $720
Removal of compressed air $0
Bearing $804
Total Costs $1,524

Your Partner for Machine Optimization

Our AIP Added Value Program is based around a simple proposition: ‘improvement pays’. By working with you throughout the AIP Value Cycle, we will help you achieve improvements in machine reliability, productivity and performance, all of which carry a tangible and measurable cost benefit – and we have the tools to prove it! That’s what we mean by improvement pays.