30215 bearing: complete specifications & equivalents
The 30215 is a ISO 355 radial bearing sized 75 x 130 x 27.25 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Bore diameter d | 75 mm |
| Outer diameter D | 130 mm |
| Width B | 27.25 mm |
| Seal / shield | open |
| Internal clearance | CN available |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Operating temperature | -30 to +120 °C |
| Mass (geometry estimate) | 1231 g |
| Standard | ISO 355 |
| Catalog version | iso355-geometry |
| Last verified | 2026-09-24 |
Source: ISO 15 boundary-dimensions standard · extracted 2026-09-24
Standard-interchange bearing: dimensions per ISO 15; CN clearance, P0 tolerance and a stamped-steel cage are catalogue defaults unless the supplier states otherwise, and mass is a geometry-derived estimate. Brand catalogue load ratings and limiting speeds for 30215 are being backfilled — use the inquiry form for certified values.
Dimensions in inches & 30200-series range
| Bore d | 2.953 in |
|---|---|
| Outer diameter D | 5.118 in |
| Width B | 1.073 in |
| ISO bore code | 15 |
| Radial section height (D−d)/2 | 27.5 mm |
| Smallest bore in 30200-series | 20 mm |
| Largest outer diameter in 30200-series | 200 mm |
| Width range across 30200-series | 15.25–41 mm |
| Bore position in 30200-series (smallest first) | 12 of 19 |
| Bore above smallest 30200-series size | 55 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 30215 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; brand-specific OEM equivalents (NSK/FAG/NTN) pending multi-source data. |
Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.
How the 30215 model number is decoded
In the 30200-series the last two digits of 30215 encode the bore: code 15 = 75 mm (code × 5 from 04 upward). The ISO 355 envelope is 130 mm outside diameter and 27.25 mm total assembly width T over the separable cone and cup — 2.953 × 5.118 × 1.073 in, with a 27.5 mm radial section height. Tapered rollers carry combined radial and single-direction axial load; bidirectional thrust needs an opposed pair (X face-to-face or O back-to-back) adjusted at fit-up. With a rotating cone on a 75 mm shaft, typical catalogue practice is a k5 shaft seat with an H7 housing bore, EP lubrication and a defined end-play setting — verify against the load direction and magnitude.
Typical equipment & failure modes
Common applications
- conveyor head and tail pulleys
- fork-lift steer axles
- industrial transmission shafts
- light-truck and van wheel hubs
- final-drive pinion and differential bearings
Known failure patterns
- cup creep and housing bore fretting when the outer ring is left without its specified press fit
- roller large-end smearing and scoring against the inner-ring guide rib from loss of the EP lubricant film
- raceway spalling at the roller-rib junction after the L10 life or sustained axial overload
- over-preload heat: a shim stack cut too thin drives contact stress up and seizes the cone on the seat
- under-preload end play that lets the rollers skid, producing noise and false brinelling
Selection pitfalls — read before you substitute
- On this 75 mm-bore 30215, thermal growth of the shaft closes up the adjusted clearance; set cold end play around 0.03–0.12 mm and recheck after the first hot run — a medium-series cone that was correct cold on the 75 mm seat can seize hot.
- The 302 light series at 75 mm bore (130×27.25 mm, 27.5 mm section) is the default general-purpose tapered row; a 32215 on the same 75 mm bore uses the same OD but a wider section for heavier load — it is not a like-for-like width swap.
- The 27.25 mm-wide 30215 ring seats against a shaft and housing shoulder whose fillet must clear the bearing chamfer: keep the corner radius small enough that the 75 mm bore and 130 mm cup seat square — an undercut beats an oversized radius, which lifts the ring and edge-loads the 27.5 mm section.
- When mounting 30215 to a 75 mm shaft, warm the cone to 80–100 °C and slide it dry to the shoulder; cooling shrinks it into its interference, whereas hammering a cold cone through a 130 mm assembly dents the tapered raceway before first run.
- Relubrication for 30215 must reach the rib-roller end contact, not just the 75 mm bore; in a hub repack, work EP grease through the roller set until it exudes at both faces of the 27.25 mm-wide assembly or the sliding rib contact starves first.
- Assign fits by which ring rotates: an interference shaft fit for a rotating cone; if the cup rotates instead, reverse the logic — a loose rotating ring creeps and frets its seat.
- A single 30215 takes thrust in ONE direction — the rollers roll toward the rib under load, so reverse thrust unloads the contact. For a wheel or pinion use an opposing 302-series pair adjusted against each other.
Frequently asked questions
What are the dimensions of a 30215 tapered roller bearing?
A 30215 single-row metric tapered roller bearing per ISO 355 has a 75 mm bore, 130 mm outer diameter and 27.25 mm total assembly width (2.953 × 5.118 × 1.073 in), a 27.5 mm radial section and roughly 1231 g geometry-based estimated mass; catalogue masses vary with roller and cage design.
How does the 30215 bore code work?
The last two digits of 30215 are bore code 15, giving 15 × 5 = 75 mm bore — the same convention as 6xx ball bearings, starting at code 04 (20 mm). The 130 mm OD and 27.25 mm width come from the ISO 355 diameter and width series, not the bore code alone.
What is the cone and cup of 30215?
Tapered roller bearings are separable: the cone is the inner ring with the tapered rollers and cage, the cup is the outer ring. 30215 denotes a matched cone-and-cup set. They are fitted separately — cone pressed on the shaft, cup in the housing — and adjusted against each other.
How is the preload or clearance of 30215 set?
At fit-up the 75 mm-bore cone is tightened against the cup while the hub is rotated, seated, then backed off to the specified end play — a typical starting range of 0.03–0.12 mm for a 75 mm bore — and locked with shims, a locknut or a spacer. Too tight overheats and seizes the rib; too loose causes skid, noise and early wear. Confirm the exact figure in the hub or axle-maker procedure.
Can 30215 take axial load in both directions?
A single 30215 takes thrust in one direction only — the roller large ends bear against the inner-ring rib under load. Bidirectional axial load requires an opposed pair: X (face-to-face) tolerates misalignment slightly better, O (back-to-back) gives a wider load centre and more moment stiffness.
Reviewed & verified by the MPN Base engineering desk against source catalog iso355-geometry on 2026-09-24. Read our editorial & correction policy.