HM212044-HM212011 bearing: complete specifications & equivalents
The HM212044-HM212011 is a ANSI ABMA 19.2 radial bearing sized 60.325 x 122.238 x 38.1 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 60.325 mm |
| Outer diameter D | 122.238 mm |
| Width B | 38.1 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 208 kN |
| Basic static load rating C0 | 244 kN |
| Limiting speed (mechanical) | 3100 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2020 g |
| Manufacturer designation | NTN 4T-HM212044/HM212011 |
| 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 | 2.375 in |
|---|---|
| Outer diameter D | 4.813 in |
| Width B | 1.5 in |
| ISO bore code | 44 |
| Radial section height (D−d)/2 | 31 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) | 77 of 148 |
| Bore above smallest 4t-inch-series size | 47.625 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| HM212044 | 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 HM212044-HM212011 model number is decoded
NTN supplies this 2.375 in (60.325 mm) shaft position as 4T-HM212044/HM212011: cone HM212044, cup HM212011, profiled rollers and a pressed-steel cage, rated 208 kN basic dynamic and 244 kN static. Reading the designation: 4T-HM212044/HM212011 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the heavy-medium HM family lettering ties the pair to its boundary plan. Contact-angle geometry of the heavy-medium HM family gives 4T-HM212044/HM212011 its radial/axial load split — at 208/244 kN the static rating is about 1.17× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for HM212011: within the heavy-medium HM family tables the HM212044 cone is listed against several cup options, and it is the cup that fixes the 122.238 mm OD and the 38.1 mm assembled width — quote the full HM212044/HM212011 pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 60.325 mm pair is misadjusted and the set will edge-load in service.
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
- rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries
- flaking on one cone only when a bent shaft loads the O/X pair unevenly
- cup creep and housing fretting when the cup seat is cut too loose for the rotating load
- pressed-steel cage pocket wear from roller skid at light radial load and high speed
- rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load
Selection pitfalls — read before you substitute
- Mount the 60.325 mm cone by induction heating (max 120 °C) and the 122.238 mm cup with a press sleeve; at 2020 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 60.325 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.
- Fit selection follows the rotating ring: a rotating cone on a 60.325 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.
- Shaft and housing fillets must clear the ring chamfers of HM212044 and HM212011; use undercut shoulders so the rings seat on the face, not on a radius.
- Shaft and housing fillets must clear the ring chamfers of HM212044 and HM212011; use undercut shoulders so the rings seat on the face, not on a radius.
- The 208/244 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM212044/HM212011; 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-HM212044/HM212011?
4T-HM212044/HM212011 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 60.325 mm bore (2.375 in), 122.238 mm outside diameter and 38.1 mm assembled width T (4.813 × 1.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 208 kN, C0 244 kN, grease limiting speed 3,100 r/min, oil speed 4,100 r/min, mass about 2020 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-HM212044/HM212011 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the HM212044 cone or the HM212011 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 208/244 kN ratings change with the cup.
What is the difference between 4T-HM212044/HM212011 and a metric ISO 355 tapered bearing?
4T-HM212044/HM212011 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 60.325×122.238×38.1 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-HM212044/HM212011 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 HM212044/HM212011 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-HM212044/HM212011 list two speeds, 3,100 and 4,100 r/min?
The lower figure, 3,100 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-HM212044/HM212011 at 4,100 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.