Static safety factor
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Mechanics · Bearings
Bearing Static Safety Factor Calculator
Evaluate the bearing static ratio separately without applying a universal threshold or automatic safety verdict.
Created v1.0
By Thibaut Grzelak, Mechanical Analysis Engineer
03
MetricResults
Equivalent static bearing load
kN
View calculation detailsFormulas, SI conversion, numerical substitution and resultsOpen ↓
Calculation note
Full calculation details
X₀ and Y₀ are user-supplied static factors and are not replaced by X and Y. C₀ is the published basic static load rating for the selected bearing. Some catalogues impose piecewise rules or a minimum P₀ value; this model only applies the entered X₀ and Y₀. The s₀ ratio is shown without a universal pass/fail threshold. Permanent deformation, shock and application-specific requirements require separate evaluation.
01Formulas and symbols
Formulas used
P₀
X₀ × Fr + Y₀ × FaEquivalent static bearing loads₀
C₀ / P₀Static safety factor02Assumptions and limits
Scope of validity
- X₀ and Y₀ are user-supplied static factors and are not replaced by X and Y.
- C₀ is the published basic static load rating for the selected bearing.
- Some catalogues impose piecewise rules or a minimum P₀ value; this model only applies the entered X₀ and Y₀.
- The s₀ ratio is shown without a universal pass/fail threshold.
- Permanent deformation, shock and application-specific requirements require separate evaluation.
03Validation example
Reference numerical case
- Fr = 6 kN, Fa = 2 kN, X₀ = 0.60 and Y₀ = 0.50 give P₀ = 4.6 kN.
- With C₀ = 23 kN, s₀ = 5.0.
- With P₀ = 0, s₀ = N/A.
04Frequently asked questions
Questions about the calculation
Are X₀ and Y₀ the same as X and Y?
No. Static factors X₀/Y₀ are distinct from dynamic factors X/Y and must come from applicable documentation.
What minimum s₀ should be used?
There is no universal threshold for every application. Check manufacturer recommendations, shock, precision requirements and design rules.
Why is s₀ N/A when P₀ = 0?
The C₀/P₀ ratio would divide by zero. N/A is more faithful than infinity or an automatic verdict.
05References
Technical references
- ISO 76:2006, Rolling bearings — Static load ratings, with ISO 76:2006/Amd 1:2017.
- ISO/TR 10657:2021, explanatory notes on ISO 76.
- Bearing manufacturer data for C₀, X₀, Y₀ and application criteria.