nner Ring and Outer Ring
Slewing ring bearings are comprised of two rings, each of which contains a precision raceway that is induction hardened on the
surface to a specified depth. Each ring is made from a medium carbon steel forging. Silverthin™ SK and ST Series bearings have
raceways constructed in a four-point contact configuration, with 45° contact angles as standard. Other raceway configurations are
available, such as crossed roller and eight-point contact. These other options are often considered in cases where very high loads
or special stiffness requirements are needed.
Rolling Elements
Precision rolling elements (specifically hardened chrome alloy steel balls for Silverthin™ SK and ST Series bearings) facilitate
relative ring rotation between the inner and outer rings. Rollers as rolling elements are also often used.
Spacers, Spacer Balls & Separators
Spacers, typically made from a plastic material, are commonly used to separate balls to prevent them from rubbing directly against
each other. Sometimes spacer balls are utilized instead of spacers. In this case these are balls that are slightly smaller than
the load carrying balls, placed between each load carrying ball. Occasionally, application parameters warrant the use of a
separator.
Mounting Holes
Mounting holes are generally spaced around the faces of the inner and outer ring along a uniform bolt circle and equal spacing.
These holes can be thru holes, tapped holes, blind tapped holes, counter-bored holes, etc. Sometimes bolt circle or spacing
requirements need to be customized to meet the demands of a specific application, in which case custom options are available. In
the case of either the standard part numbers listed in this catalog, or other custom versions provided by Silverthin™, the
equipment designer, manufacturer, or user is responsible to determine that the mounting design is adequate.