many custom bearings designed to optimize bearing performance for specific
applications. Special features include changes in radial play, lubricants,
materials, preloading and design. Contact your RBC Sales Engineer for
your custom bearing needs.
Challenge us: There are many design options available to solve difficult application
The standard bearings
shown in the catalog have SAE 52100 steel rings and balls. RBC Thin
Section Ball Bearings can be manufactured from other specialty bearing
steels to provide corrosion resistance, high temperature capability,
alternative load capacity or chemical compatibility.
has manufactured thin section ball bearings from SAE 440C stainless
steel to provide corrosion resistance. As an alternative to stainless
steel rings, the entire surface of the rings can be plated with nodular
thin dense chrome (TDC). This plating, which meets AMS 2438, achieves
a molecular bond that will not flake, peel or separate from the base
material. The TDC plate has a hardness of HRC 70 - 78 and can withstand
temperatures well beyond the range of the base material.
Special RBC Thin
Section Ball Bearings have been manufactured from Aluminum, 300 Series
Stainless Steel, 17-4 Stainless Steel, and other metals.
special ball materials available include 440C Stainless Steel, 300 Series
Stainless Steel, Silicon Nitride and M-50 Steel.
Many different lubricants
are available from RBC for special applications. Greases which are designed
specifically for high speed, low torque, water resistance, high temperature,
oscillatory motion and food machinery can be provided. Additional lubricants,
such as dry film, are suitable for use in vacuums and space applications.
Standard seals for
thin section ball bearings are molded from elastomers (Buna N). Polytetra-flouroethylene
(PTFE) seals, fiber glass reinforced PTFE seals, stainless steel shields
and many other options are available for low torque and other special
The radial play
(diametral clearance) of a thin section ball bearing will need to be
predetermined if mounting fits other than those recommended are used.
Special radial play may be required for a temperature differential across
the bearing, for housing and shaft materials that have different coefficients
of thermal expansion, or to change operating characteristics of the
bearing. Radial preloaded bearings are measured to meet bore and O.D.
tolerances prior to preload.
bearings are ground so that there will be a light axial preload induced
on the bearing at nominal conditions. In some applications increased
bearing stiffness may be required. In these cases the duplex grinding
can be done such that a heavier axial load is induced in the mounted
bearing. This load can be increased or decreased to meet the requirements
of a particular application. Consult your RBC Sales Engineer for special
such as flanges, anti-rotation tabs and mounting holes can be incorporated
on the inner and outer rings. Mating parts, such as gears and housings,
may be integrated into the bearing rings for improved performance and
Standard RBC Thin
Section Ball Bearings, KA through KG and JU series, are manufactured
with brass separators. The KAA series contains nylon separators. The
A-Type bearings contain one-piece circular pocket separators, while
the C and X-Types have snap-over separators. The four basic separator
materials are brass, nylon, phenolic and stainless steel. The graph
below schematically illustrates the effects of cage design and material
on bearing performance. Specific material advantages and limitations
are listed on page 39. In comparison, the one-piece circular pocket
design may reach roughly two times the speed of the snap-over design.
Exact speed limits depend on bearing size, bearing type, lubrication
and loading. For assistance in selecting the appropriate separator for
special applications, contact your RBC Sales Engineer.