Timken Super Precision Bearings for Machine Tool Applications

ENGINEERING
A
Typical considerations in machine design also include optimization
of controllable variables affecting application performance:
• Bearing design.
• Bearing shaft and housing arrangement; shaft and housing
material.
• Installation and handling requirements of the bearing, as well
as shaft and housing preparation.
• Presence of adequate sealing for the exclusion of
contaminants; types of foreign materials possible.
• Lubricating method (lubrication type and delivery system).
• Maintenance procedures and intervals.
Boundary (or fixed) conditions that should be taken into consideration
include:
• External loads, including radial, thrust, moment, shock and
combination loads.
• Acceleration and deceleration levels.
• Operating temperature range (including extreme limits and
thermal cycling).
• Other environmental factors, such as humidity, fluids,
vibration, debris, magnetic fields.
• Spatial constraints.
Performance expectations (or desired results) to consider
include:
• Rotational accuracy and repeatability (e.g., service precision
level).
• System rigidity (axial or radial stiffness).
• Application service life.
• Speed.
Since the rolling bearing is an integral part of the machine, looking
at the key operating parameters of the system also will help focus
on the most viable bearing solution.
Once these conditions and expectations have been identified and
prioritized, the most appropriate bearing type(s), size(s), and part
number(s) that meet the basic application requirements can be
selected.
BEARING PERFORMANCE CHARACTERISTICS
The following matrix should be viewed only as a general overview
of bearings available from Timken and their general performance
characteristics. Bearing selection is not a clear-cut, simplistic
procedure, but rather a sequence of interdependent tasks that must
take into consideration customer goals, manufacturing economics,
design expectations and, above all, human safety.
Most machine tool applications require bearings with extreme
precision, designed specifically to meet the boundary conditions
and performance requirements. Timken ® super precision bearings
offer quality and precision tolerances to help customers achieve
target job requirements and production throughput. It is always
prudent to enlist the assistance of your Timken representative to
achieve optimum results.
14 TIMKEN MACHINE TOOL CATALOG