Continuous Annealing Process

A continuous annealing line at a steel plant was experiencing an average of 17 hours of downtime per year, costing approximately €21,915 per hour of failure. NSK engineers who analysed the failed bearings determined that both the bearing type and the sealing arrangement were inadequate for the application; the ideal solution was multi-row sealed cylindrical roller bearings (crane sheaves).

• Steel strip production process — 8 machines; average service life 4 months
• Heavy load, low speed application; contamination and lubrication problems
• Bearing failure caused 17 hours of lost production per year; over 119 hours in 7 years
• A Crane Sheave Bearing Unit with integrated seal arrangement and revised housing design was proposed
• Post-trial inspection found no bearing damage; life extended beyond 3 years
• Expected service life of the new NSK design: 5 years

Technical Features: Full-Complement Cylindrical Roller Bearing for Crane Sheaves

• Better contact seals; sealing against water and foreign matter
• High load carrying capacity; higher radial and axial capacity
• Highly corrosion-resistant phosphate coating
• Relubrication holes in inner and outer rings
• Bearings pre-lubricated with lithium grease
• Can be mounted with DIN 471 retaining rings
• Suitable for outdoor use thanks to the coating