HM218248-HM218210 bearing: complete specifications & equivalents
The HM218248-HM218210 is a ANSI ABMA 19.2 radial bearing sized 89.974 x 146.975 x 40 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 89.974 mm |
| Outer diameter D | 146.975 mm |
| Width B | 40 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 252 kN |
| Basic static load rating C0 | 340 kN |
| Limiting speed (mechanical) | 2400 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2550 g |
| Manufacturer designation | NTN 4T-HM218248/HM218210 |
| Standard | ANSI ABMA 19.2 |
| Catalog version | NTN 2203E 2026-09-25 |
| Last verified | 2026-10-01 |
Source: catalog reference (NTN 2203E 2026-09-25) · extracted 2026-10-01
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN 2203E 2026-09-25); 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 & 4t-inch-series range
| Bore d | 3.542 in |
|---|---|
| Outer diameter D | 5.786 in |
| Width B | 1.575 in |
| ISO bore code | 48 |
| Radial section height (D−d)/2 | 28.5 mm |
| Smallest bore in 4t-inch-series | 12.7 mm |
| Largest outer diameter in 4t-inch-series | 260 mm |
| Width range across 4t-inch-series | 10.998–77.788 mm |
| Bore position in 4t-inch-series (smallest first) | 107 of 148 |
| Bore above smallest 4t-inch-series size | 77.274 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| HM218248-210 | SKF | full Dimensions and internal design equivalent — standard interchange. | Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier. |
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 HM218248-HM218210 model number is decoded
4T-HM218248/HM218210 belongs to the NTN inch 4T tapered roller range (heavy-medium HM family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-HM218248/HM218210 are separately stocked parts: a worn HM218210 cup can be replaced against the existing HM218248 cone, provided the new cup carries the identical reference — pairing across references changes the 40 mm assembled width and the rating. Grease relubrication at the 2,400 r/min limiting speed targets the cone-rib contact; sustaining 3,200 r/min needs an oil supply directed at the large roller ends. Cup-side note for HM218210: within the heavy-medium HM family tables the HM218248 cone is listed against several cup options, and it is the cup that fixes the 146.975 mm OD and the 40 mm assembled width — quote the full HM218248/HM218210 pair, never the cone alone. Fillet radii must clear the chamfers of the HM218248 cone and HM218210 cup; undercut shoulders seat the rings fully instead of bridging on a radius.
Typical equipment & failure modes
Common applications
- off-highway and forestry machine axles
- marine winch and deck-machinery shafts
- crusher and screening-plant eccentric shafts
- heavy truck and bus drive-axle differentials
Known failure patterns
- cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film
- false brinelling on a stationary pair exposed to vibration during transport or standby
- preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play
- cage damage from a mounting blow transmitted through the roller complement
- brinell marks on cone and cup raceways from impact during handling or hammer fitting
Selection pitfalls — read before you substitute
- Mount the 89.974 mm cone by induction heating (max 120 °C) and the 146.975 mm cup with a press sleeve; at 2550 g a cocked ring brinells the raceway directly.
- The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 89.974 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.
- Inch and metric bores collide on paper — 89.974 mm is 3.542 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.
- Quote the full HM218248/HM218210 pair at ordering: the HM218248 cone also ships against sibling cups, and a cup from another reference changes the 40 mm assembled width and the rating.
- Shaft and housing fillets must clear the ring chamfers of HM218248 and HM218210; use undercut shoulders so the rings seat on the face, not on a radius.
- The 252/340 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM218248/HM218210; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive.
Frequently asked questions
What are the dimensions and catalogue ratings of NTN 4T-HM218248/HM218210?
4T-HM218248/HM218210 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 89.974 mm bore (3.542 in), 146.975 mm outside diameter and 40 mm assembled width T (5.786 × 1.575 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 252 kN, C0 340 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 2550 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-HM218248/HM218210 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the HM218248 cone or the HM218210 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 252/340 kN ratings change with the cup.
What is the difference between 4T-HM218248/HM218210 and a metric ISO 355 tapered bearing?
4T-HM218248/HM218210 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 89.974×146.975×40 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting.
What does the 4T prefix on 4T-HM218248/HM218210 mean?
4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM218248/HM218210 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-HM218248/HM218210 list two speeds, 2,400 and 3,200 r/min?
The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM218248/HM218210 at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN 2203E 2026-09-25 on 2026-10-01. Read our editorial & correction policy.