Mood, Industries, 1600x230

Introduction

A worldwide manufacturer of automotive components was experiencing significant unplanned downtime due to the failure of the Ball Screws in the Machining Center. This had a major effect on the manufacturing output resulting in increased costs and reduced machine reliability. 6 month was the average life of the Ball Screws. NSK analyzed three of the failed Ball Screws to determinate the main reason for the failures. NSK's Technical Department developed a special design to improve the technical characteristics, especially the high-performance sealing design. Two Ball Screws were installed in the most critical points in the plant. The product testing was successful. Reduced machine downtime and a major increase in ball screw life were achieved.

  • Machining Centre
Ball Screw X1 Sealing concept
  • Ball Screw with High-performance X1 Seal Design

Key Facts

  • Machine center with very arduous working conditions
  • Failure of Ball Screws due to high loading and agressive environment
  • NSK Solution: High-performance seals and high-speed/high-load Ball Screws
  • Nut design Ball Screws to maintain better stiffness and improved quality
  • Increased lifetime by 6 times
  • Reduction in production downtime and material costs

Value Proposals

  • Plant survey including inspection of  the machines environment and working conditions 
  • NSK analyzed three Ball Screws to observe the running paths and lubrication conditions
  • NSK Technical Department designed a special Ball Screw that could be assembled without any change from  the customer

Product Features

  • High-performance seal design to work in a harsh environments
  • Decrease in the operating temperature and wear (precision and preload)
  • Increase of operating life, due to the greater load capacity and the lower preload
  • Reduction of the torque required, due to a lower degree of preload, with a corresponding reduction of the energy consumption of the machine
  • Reduced maintenance with K1 lubrication system 
  • Longer grease life 
  • Optimum lubrication even with high loads and harsh operating conditions
  • No contamination of cutting/cooling liquid with grease
Cost Saving Breakdown
Before Cost p.a. NSK Solution Cost p.a.
Bearing Costs: Costs for Ball Screws x 2 machines $8,980 Bearing Costs: Costs for Ball Screws x 2 machines $4,276
Costs of lost production: Production costs: 6 hours/stop x 12 stops x 360 pieces/hour x $10.85/piece $277,095 Costs of lost production: No failures in 36 months $0
Engineering Costs: 4 hours for each Ball Screw x $54.28/hour x 14 changes $2,993 Engineering Costs: 4 hours for each Ball Screw x $54.28/hour x 2 changes $427
Total Costs $289,068 $4,703

Reference:SS-E-7028