Page 6 - NSK_CAT_E1102m_A7-141

2. BEARING SELECTION PROCEDURE Evaluation of accuracy Examination of fitting

The number of applications for rolling bearings is Then the size of the bearing is chosen to satisfy the A Running accuracy Page number A Operating conditions Page number
almost countless and the operating conditions and desired life requirement. When doing this, in addition A Rotational stability A19 A Magnitude and character- A82
environments also vary greatly. In addition, the diversity to fatigue life, it is necessary to consider grease life, A Torque fluctuation A18, A37, A81 A82, A83
of operating conditions and bearing requirements noise and vibration, wear, and other factors. A19 istics of loads
continue to grow with the rapid advancement of There is no fixed procedure for selecting bearings. It is A Temperature range A83
technology. Therefore, it is necessary to study bearings good to investigate experience with similar applications Page number A Materials, size, accuracies A84, A100
carefully from many angles to select the best one from and studies relevant to any special requirements for A95
the thousands of types and sizes available. your specific application. When selecting bearings for Selection of bearing of shaft and housing
Usually, a bearing type is provisionally chosen new machines, unusual operating conditions, or harsh accuracy class A18
considering the operating conditions, mounting environments, please consult with NSK. A98 Determination of fitting
arrangement, ease of mounting in the machine, The following diagram (Fig.2.1) shows an example of A Fitting
allowable space, cost, availability, and other factors. the bearing selection procedure. Examination of A Difference in temperature
internal clearance
between inner and outer
rings
A Speed
A Misalignment of inner and
outer rings
A Amount of preload

A Operating conditions and required Study of cage Determination of Examination of special Page number
performance internal clearance specifications A57

A Environmental conditions A Speed A Operating temperature
A Dimensions of shaft and housing A Noise A Environment (seawater,
A Operating temperature
Evaluation of A Allowable space Page number A External vibration and shock vacuum, gases, chemicals,
bearing types A Magnitude and direction of loads A18, A38 A Rapid acceleration and etc.)
A Vibration and shock A18 A Type of lubrication
A Operating speed, maximum speed A18 deceleration
A Misalignment of inner and outer A18, A37 A Moment load and misalignment
A18
rings Selection of cage type Selection of special
A Fixing in axial direction and mounting A20 to A23 and material material, heat treatment
for dimensional stability
arrangement A19
A Ease of bearing mounting and Examination of A Operating temperature range Page number
A19 lubricating A Speed A106, A107, A110, A112
dismounting A19, A96 methods A Lubricating methods A37
A Sound and torque A Type of seals A105
A Required rigidity A Maintenance and inspection A102
A Availability and cost A123
intervals

Determination of bearing Selection of lubricating
type and mounting method, lubricant, and
arrangement
type of seals
Determination of A Expected life of machine Page number Examination of Page number
bearing size A Dynamic and static equivalent loads A24, A25 ease of mounting/ A Procedure for mounting and A116, A121
A Speed A30, A32 dismounting dismounting
A Permissible static load factor -- A116, A121
A Permissible axial loads (in the case of A32 A Necessary equipment A100
A33 A Dimensions affecting
cylindrical roller bearings)
mounting

Determination of bearing size Determination of dimensions
affecting mounting and
procedure for mounting/
dismounting

Fig. 2.1 Flow Chart for Selection of Rolling Bearings Final specifications for
bearing and surrounding

parts

A 16 A 17