A rolling thrust bearing carries load along a shaft axis while permitting rotation. This calculator applies the basic L10 rating-life equation to a constant pure-axial case using catalogue C and either the ball-bearing exponent 3 or roller-bearing exponent 10/3.
Thrust Bearing Interactive Calculator
Enter equivalent axial load, catalogue dynamic axial rating, constant speed and bearing-type selector (0 ball, 1 roller). Results are basic rating life, not guaranteed service life.
Equation Used
- Constant speed and constant equivalent dynamic axial load.
- Entered C is the applicable catalogue basic dynamic axial load rating in the same force unit as P.
- Exponent is 3 for ball bearings or 10/3 for roller bearings.
- The displayed pure-axial case uses P=Fa only where the selected bearing catalogue permits it.
- Lubrication, contamination, reliability adjustment, misalignment, mounting, temperature, minimum load, static safety and duty cycle are omitted.
Rolling Thrust-bearing Load Path
A rolling thrust bearing transfers axial load from one race through balls or rollers to the other race while allowing relative rotation. The bearing type, direction capability and permissible loading must come from its catalogue.
The figure is a schematic ball-thrust section. It does not prescribe groove geometry, fits, alignment or lubrication.
What This Calculator Does
The tool applies the basic, unadjusted rating-life equation to constant load and speed. It supports the standard exponent 3 for ball bearings and 10/3 for roller bearings.
It is an initial catalogue calculation only, not a bearing-selection approval or service-life guarantee.
Basic Rating Life
L10h = 106L10/(60n)
p = 3 ball; 10/3 roller
L10 is the life reached or exceeded by 90% of a sufficiently large group of apparently identical bearings under the defined basic conditions. Actual service life can differ.
Worked Basic-life Example
For P=20 kN, C=80 kN, n=100 rpm and a ball-bearing exponent p=3, C/P=4, L10=64 million revolutions and L10h is about 10,667 hours. The C needed for a 10,000-hour target in this same simplified case is about 78.3 kN.
Model Boundary
- Calculated: basic unadjusted L10 from entered catalogue rating, equivalent load, constant speed and standard exponent.
- Pure-axial simplification: P=Fa only when applicable to the selected thrust bearing.
- Not calculated: combined-load factors, duty cycle, reliability adjustment, lubrication, contamination, fatigue load limit, misalignment, mounting, preload, temperature, minimum load, static safety, wear or suitability.
Frequently Asked Questions
What does L10 mean?
It is a statistical basic rating life reached or exceeded by 90% of a sufficiently large group of apparently identical bearings under the rating definition.
Which exponent should I use?
Three for ball bearings and 10/3 for roller bearings.
Is P always equal to axial load?
No. P equals axial load only for the stated pure-axial case and a compatible bearing type; other loading requires the manufacturer’s equivalent-load factors.
Is calculated life guaranteed service life?
No.
Does the tool check static capacity or minimum load?
No.
Can it select a bearing?
No. Apply the manufacturer's complete catalogue procedure.
References
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