Page 109 - Rollingbearings

SKF life testing
SKF life testing

SKF carries out life testing in the
ISO 17025 accredited SKF Engineering and
Research Centre in the Netherlands,
together with the other SKF group research
and testing facilities.
The purpose of this life testing is to
improve the design, the materials and the
manufacturing processes of bearing prod-
ucts, and the engineering analysis tools
required for the design of bearing
applications.
Typical life testing activities include tests
on bearing population samples under differ-
ent conditions, such as:

• full ilm lubrication conditions
• boundary and mixed lubrication
conditions
• predeined contamination conditions of
the lubricant

Apart from testing in different conditions,
SKF life tests are performed to:
• verify the data published in product
catalogues
• audit the quality of the manufacturing of
SKF bearings
• research how lubricants and lubrication
conditions inluence bearing life
• support the development of rolling contact Bearing size
fatigue and friction models
• compare SKF products with competitors’
B.3
products
Life tests are sophisticated and wide-rang-
ing and are run under strictly controlled con-
ditions. Post-test investigations with state- Table 8
of-the-art equipment make it possible to
Guideline values for the static safety factor s 0 – for continuous and/or occasional loads –
investigate the factors that affect the life of roller bearings 1)
the bearings in a systematic way. Certainty of load level Continuous motion Infrequent motion
As an example, the SKF Explorer bearing Permanent deformation Permanent deformation
design is the result of optimizing inluencing acceptance acceptance
factors determined by analytical simulations Yes Some No Yes
and experimental veriication.
High certainty 1 1,5 3 0,8
For example, gravity loading
and no vibration
Low certainty ≥ 2,5 ≥ 3 ≥ 4 ≥ 2
For example, peak loading

1) For spherical roller thrust bearings, use s 0 ≥ 4.

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