Slewing Ring Bearings are large-size rolling bearings that can accommodate axial, radial and moment loads acting either singly or in combination and in any direction .They can perform both slewing (oscillating) movements as well as rotational movements.
A Slewing Ring Bearing consists of an inner ring, an outer ring and rolling elements (balls or cylindrical rollers) that are separated by polyamide spacers .The rings, one of which usually incorporates a gear ,are provided with holes to accommodate attachment bolts. The holes may be threaded. Generally , only the raceways in the rings are hardened and precision-ground.Integral seals made of acrylonitrile-butadiene rubber (NBR) keep the lubricant in, and contaminants out of the bearing. Slewing ring bearings are re-lubricated through grease fittings to reduce maintenance and operating costs.
Compared to traditional pivot arrangements, slewing ring bearing arrangements provide many design and performance advantages. The compactness and large inner diameter simplify the design of the bearing arrangement and its associated components .The low sectional height of these bearings means that the pinion lever can be kept short. In most cases only flat mounting surfaces on the associated components are needed.
Slewing Ring Bearings were originally designed to be mounted only on horizontal support structure, but can now be used successfully in vertical bearing arrangements .
Slewing Ring Bearings perform extremely well in a variety of applications such as:
¤ Access platforms
¤ Bucket wheel excavators
¤ Conveyor booms
¤ Cranes of all type
¤ Small ,medium and large excavators
¤ Indexing tables
¤ Ladle turrets
¤ Offshore applications
¤ Robots
¤ Railway bogies
¤ Rotary platforms
¤ Stackers
¤ Solar mirrors
¤ Tunnel boring machines
¤ Wind turbines
