Slewing bearing comprises inner ring, outer ring, and rolling element assembly between the rings. And it’s common to see a slewing bearing has more than one inner ring or outer ring for various purposes, i.e. easy installation and maintenance, higher level of sealing requirement, super big slewing diameter and more. Rings usually incorporate teeth. Together with attachment holes in both rings, they enable an optimized power transmission with a simple and quick connection between adjacent machine components. The bearing raceways, in conjunction with the rolling elements and cages or spacers, are designed to accommodate loads acting singly or in combination, and in any direction.
Factors in selecting a slewing bearing:
- Accuracy
- Magnitude and direction of loads
- Permissible operating temperature
- Vibration
- Operating speed
- Sealing requirement
Structures
Single row four points contact ball
Optimal economy and capacity for given dimensions or when replacing existing multi-bearing arrangements.
Double row ball
80% increase in capacity compared to a same-sized single row four-point contact ball bearings.
Single row crossed cylindrical roller
High stiffness and constant resistance to rotation.
Ball and roller combined
Roller is used mainly to cope with heavy load while ball to enable speed of higher level, combined type is designed to balance the two concerns.
Triple row roller
Provide highest capacity for a given diameter.
Wire race way
60% lighter compared to same-sized all-steel bearings.