HK2512F bearing: complete specifications & equivalents
The HK2512F is a ISO 3245 radial bearing sized 25 x 32 x 12 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 25 mm |
| Outer diameter D | 32 mm |
| Width B | 12 mm |
| Seal / shield | open |
| Basic dynamic load rating C | 11.1 kN |
| Basic static load rating C0 | 15.2 kN |
| Fatigue load limit Pu | 1.85 kN |
| Limiting speed (mechanical) | 6500 rpm |
| Mass | 21 g |
| Manufacturer designation | HK2512F |
| Standard | ISO 3245 |
| Catalog version | CAT. No. 2203-3/E 2024 |
| Last verified | 2026-09-25 |
Source: catalog reference (CAT. No. 2203-3/E 2024) · extracted 2026-09-25
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (CAT. No. 2203-3/E 2024); NTN® is a trademark of NTN Corporation, used here for identification only — mpnbase is not an authorized NTN distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at ntnglobal.com.
Dimensions in inches & HK-series range
| Bore d | 0.984 in |
|---|---|
| Outer diameter D | 1.26 in |
| Width B | 0.472 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 3.5 mm |
| Smallest bore in HK-series | 3 mm |
| Largest outer diameter in HK-series | 58 mm |
| Width range across HK-series | 6–38 mm |
| Bore position in HK-series (smallest first) | 18 of 24 |
| Bore above smallest HK-series size | 22 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the HK2512F model number is decoded
NTN HK2512F belongs to the HK-series of open-end drawn-cup needle roller bearings (ISO 3245).Fw = 25 mm names the shaft journal that doubles as the inner raceway; around it the drawn cup measures 32 mm outside and 12 mm across. There is no separate inner ring — the thin-walled cup is drawn from sheet steel, hardened, and press-fitted into the housing, giving the smallest radial section of any rolling bearing at this shaft size. The F suffix marks NTN's caged drawn-cup execution: a formed steel cage spaces the rollers, lowering friction versus full-complement drawn cups. Mid-size drawn cups like this appear throughout passenger-car and light-truck transmissions, pressed into cast housings where a machined ring would not fit. Agricultural PTO shafts and small tractor linkages use this size at the pivot points: the cup is pressed into a welded eye and forgotten until the implement is overhauled. Mounting this size in a split housing needs the cup pressed into one half only, with the joint face relieved so the shell is not pinched when the case bolts come up to torque.
Typical equipment & failure modes
Common applications
- industrial gearbox lay shafts
- hydraulic pump and motor shafts
- compressor crankshaft supports
- lightly loaded high-speed idler positions where roller skidding must be watched
Known failure patterns
- cage wear or fracture from sustained operation near the limiting speed
- cup cracking from an oval or tapered housing bore distorting the thin shell
- fretting of the cup outer surface in a soft or worn housing seat
Selection pitfalls — read before you substitute
- The HK2512F drawn cup is a thin shell that takes the shape of its housing: the housing bore must be machined to tolerance (typically N6/N7 for steel housings) — a worn or oval seat distorts the cup and cuts life.
- Mid-size cups like HK2512F (25 mm shaft) inherit the shape of their seat: a scored or oval housing bore from the previous bearing will cut the new bearing's life short.
- The cage in HK2512F guides the rollers but is not a seal: it retains nothing against dust or washdown, so the housing still needs its own sealing arrangement at 25 mm.
- The 12 mm standard width of HK2512F is the general-purpose section at 25 mm shaft; wider HK variants in the same 25×32 mm envelope carry more load and are not interchangeable if the housing width is fixed.
Frequently asked questions
Does HK2512F need a hardened shaft?
Either the 25 mm shaft journal must be hardened to 58–64 HRC and ground to Ra ≤ 0.2 µm, or you can fit the matching inner ring (IR20x25x12.5) so a standard unhardened shaft can be used.
What are the dimensions of a HK2512F needle roller bearing?
A HK2512F drawn-cup needle roller bearing has a 25 mm shaft diameter (Fw, under-roller diameter), 32 mm outside diameter and 12 mm width, per ISO 3245 boundary dimensions. It has no inner ring — the shaft journal serves as the raceway.
What does Fw mean on a HK2512F drawn-cup bearing?
Fw is the under-roller diameter — the diameter of the shaft journal on which the needle rollers run directly. For HK2512F, Fw = 25 mm, so the shaft must be machined to 25 mm, hardened to 58–64 HRC and ground, unless a separate IR inner ring is fitted.
Can a HK2512F needle roller bearing carry axial load?
No. Drawn-cup needle roller bearings like HK2512F carry radial load only and provide no axial shaft location. Axial forces must be carried by separate thrust washers or a locating bearing in the arrangement.
Reviewed & verified by the MPN Base engineering desk against source catalog CAT. No. 2203-3/E 2024 on 2026-09-25. Read our editorial & correction policy.