Ball Bearing Number Decoder, L10 Life and Load Calculator

The designation is split into series and bore code. Four-digit coded bores use $d=5b$ mm for codes 04–96, with 00–03 treated as 10, 12, 15 and 17 mm. Selected three-digit miniature series use the final digit as a direct bore size. Family and dimension-series interpretation follows NSK E1103c Part A, attached PDF pp. 61–62 (printed A120–A123). Dimensions D and B are exact maker-catalogue lookups from SNR 2019, attached PDF pp. 8, 9, 11 and 13. The ISO 15:2017 general plan supplies the dimension-series context; no ISO table is reproduced.

For pure radial loading of a deep-groove bearing, $P=F_r$. Combined mode uses $P=F_r$ when $F_a\le eF_r$, otherwise $P=XF_r+YF_a$. X, Y and e must be supplied together from the applicable maker table, including its dependence on axial load, static rating and internal clearance. The example factors 0.56, 1.67 and 0.26 are from NSK's 6208 worked example, attached PDF p. 28. They are not selected automatically for another bearing. Other radial ball-bearing families use a maker-derived equivalent dynamic load entered directly.

For ball bearings, the ISO 281:2007 basic rating-life relation is $L_{10}=(C/P)^3$ in million revolutions. Revolutions per hour are converted explicitly from rpm. Hours are $L_{10h}=10^6 L_{10}/n_h$. The optional selected life is $L_{nmh}=a_1 a_{op}L_{10h}$, with a supplied operating factor (aISO or a compatible maker factor); its correlation is not implemented. Basic and selected lives remain separate.

Algebraic inversion gives $C_{req}=P[N_t/(a_1a_{op})]^{1/3}$ and $P_{max}=C/[N_t/(a_1a_{op})]^{1/3}$, where $N_t$ is the target in million revolutions. With adjustment disabled, the factor product is one. The load sweep varies P only and does not reselect catalogue coefficients.

Constant load magnitude, direction and speed; individual radial ball bearing; conventional rolling-contact fatigue model. C and P use the same force unit. Loads are nonnegative magnitudes, not signed shaft forces. Load reactions, dynamic amplification and service factors must already be included in the entered loads.

C is supplied by the user from the exact maker's catalogue, including any required temperature or material correction. Its default is SNR open 6205, 14.80 kN, attached PDF p. 11. The decoder never assigns ratings from a size or suffix. Changing the designation retains the rating input.

Suffix meanings are common conventions, not a complete manufacturer translation. For example, SNR commonly writes EE, SKF 2RS1 and NSK DDU for two contact seals; generic 2RS must be confirmed with the maker. C3 means greater clearance than CN; it is neither a precision grade nor an automatic life factor. The drawing illustrates deep-groove construction and is not a manufacturing section or a drawing of every decoded family.

Supports the listed metric radial ball-bearing prefixes and bore codes 00–96; miniature decoding is limited to prefixes 60, 62 and 63 with a nonzero last digit. D and B are provided only for 44 exact catalogue rows. Five-digit aliases such as 61805, slash bores such as 62/22, special bores, inch bearings, thrust bearings, roller bearings and special prefixes are outside this decoder.

Combined-load mode applies only to single-row deep-groove ball bearings. For angular contact and self-aligning types, supply P from the maker; opposed arrangements can require induced-thrust and preload analysis. No check of axial capacity or static rating C0 is performed.

L10 is a population fatigue rating at 90% reliability, not a guaranteed service interval. The optional factors are user-supplied; no lubrication, contamination, fatigue-load-limit or aISO correlation is evaluated. Do not infer a probability from an arbitrary operating factor or combine incompatible factor systems.

The maximum P result is solely the equivalent dynamic load meeting the selected fatigue-life target. It is not a permissible shaft force, a static safety limit or a speed approval. Zero speed requires static assessment. NSK's ISO 281:2007 modified-life guidance excludes P > 0.5 C or loads above the static rating C0. This tool warns above P = 0.5 C in either life mode and replaces the target success message with a maker-applicability reminder. Numerical life results beyond this boundary are arithmetic estimates, not validated design predictions. C0 is not entered or checked, so P ≤ 0.5 C alone does not establish static safety. Reduce the load or choose an appropriate bearing, and confirm heavy-load applicability and static safety with the maker. Very light loads may cause skidding. Check maker limits, lubrication, fits, mounted clearance and alignment separately. For design decisions, use ISO 281:2007 and ISO 15:2017 in context and check against the standard in force.