Bearingizing Selection and Operation Guide0 pages

Cogsdill Tool Products, Inc.
Bearingizing
tools
The Bearingizing Tool combines
roller burnishing with peening
action. As the tool is rotated at a
high speed the rolls spin, rise, and
fall over a cammed arbor, delivering
up to 200,000 rapid fire blows per
minute to the work surface. The
peaks and valleys of the machined
surface are compacted into a
smooth, hardened, and ultrafine
The Bearingizer may be
the tool of choice where the
following conditions exist:
■
Parts with thin walls —
Bearingizing eliminates
barrel-shaping of the part.
■
surface finish.
Parts with irregular wall
thicknesses — the
Bearingizing tool will produce
a very round hole, whereas the
Roll-a-Finish® tool might
generate a slightly egg-shaped
hole, due to variations in wall
thickness.
■
■
Applications where porosity
is an issue (e.g.,
oil-impregnated bearings) —
the smaller “footprint” of the
Bearingizing roll leaves pores
in the surface intact.
Applications where very
tight tolerances must be
held — the Bearingizer
reduces springback in the
work surface material. The
Bearingizing tool can, in some
materials and with proper part
preparation, hold size as close
as ±.0001 inch (.002mm),
while the Roll-a-Finish tool can
achieve tolerances of ±.00025
inch (.006mm).
Where the above conditions do
not exist, the Roll-a-Finish® tool
would generally be the tool of
choice, for two reasons:
(1) the relatively wide adjustment
range of the Roll-a-Finish tool,
which is typically .040 inch
(1.01mm), and
(2) the ease of adjustment, with the
castellated adjusting collar on
the Roll-a-Finish tool.
The Bearingizing tool features a
greater number of rolls, and rolls of
a smaller diameter, as compared to
the Roll-a-Finish tool, and can only
be adjusted by change of rolls. The
Bearingizer also requires a closer
presize than the Roll-a-Finish tool.
But where the above conditions do
exist, the Bearingizing tool should be
considered.
While the Roll-a-Finish Tool
increases surface hardness by about
5 to 10%, Bearingizing increases
hardness by 10 to 30%, but with less
surface penetration.
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