special constructions

Cage designs

Cage designs are used in slewing bearings that are subject to high loads, torque, or rotational speeds. Due to these conditions, it is often not possible to separate the rolling elements (balls or rollers) with plastic spacers, which are used for most standard applications. Our cage designs are available in brass or steel design. Depending on the type of slewing bearing and the particular application, the cages are either assembled as a complete unit or in segments.


Surface coating

DV-B Slewing bearings have a high surface quality before shipment and are normally not subject to any further surface treatments. However, slewing bearings can be coated to ensure an even higher surface protection. The range of protections spans from simple corrosion protection coatings to multilayer coating systems in compliance with guidelines for coating thickness, RAL-colour numbers and more. As an alternative to painting systems slewing bearings can be supplied with yellow-chromated surface protection. A passivation layer of a few microns only is formed on the surface, having a good corrosion protection effect without influencing the dimensions significantly. A particular feature is the zinc flame-sprayed surface coating. The layer of zinc that is applied protects the slewing bearing for a very long period of time, even with adverse ambient conditions, and is often applied to slewing bearings on wind turbines and offshore constructions.

 


Axial ball bearings

This type of bearing is suitable for sustaining very high axial pressure loads. In each case a raceway shell is manufactured in an upper and lower ring, in which balls roll off. Due to the design, only very small radial loads and tilting moments can be transmitted depending on the existing axial load. This type of bearing is not self-holding and will be supplied unassembled.

 


Types with increased number of screws

For load combinations with high tilting moments and low axial loads as well as for slewing bearings with a suspended position of installation, it is often the carrying capacity of the bolted connection and not the raceway geometry that is decisive to the dimensioning. In order to avoid an increase in the bearing size, DV-B offers special solutions in the form of increasing the number of fastening bolts or enlarging the borehole diameter. When transmitting load cases, DV-B examines the bolted connection from the start and, if necessary, suggests a suitable solution.