The reference tables behind every bearing quotation: tolerances, fits, load ratings, and the standards they come from. Written for engineers who need the number now and the reasoning behind it, not a reprint of the standard.
Bore and outside diameter deviation, inner ring runout Kia, the ABEC / ISO / DIN / JIS class equivalence chart and the radial internal clearance ranges.
7 bore steps · 5 classes · C2 to C5The tolerance unit formula, IT5 to IT11 values for the common size steps, and the split of shaft and housing zones by load direction.
9 size steps · 9 application fitsWhat C and C0 mean, the L10 and L10h equations, the C/P life table, reliability factors above 90 %, and equivalent load P by bearing type.
Life table · a1 factors · e and YWhich standard answers which question - boundary dimensions, tolerances, ratings, and the supporting standards for clearance, vibration, damage and lubrication.
23 standards indexedSelection normally runs in one direction: the load and speed decide the bearing type and size, the size decides the bore, and the bore decides the fit and the clearance. Each of those steps has a table here, plus a calculator that does the arithmetic for a specific number.
The values here are reproduced from the ISO tables for the common size ranges so you can screen a design quickly. Production and inspection decisions should be taken against the full current standard, and for a specific part against its own catalogue page.
Enter a bore or outside diameter and read the permitted limits for each class.
L10 and L10h from C, P and speed, and the C you need for a target life.
Length, force, torque and pressure, plus inch to metric bore conversion.
Multiply bore by speed and check the result against indicative dn guidance.
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