HM807044-HM807010 bearing: complete specifications & equivalents
The HM807044-HM807010 is a ANSI ABMA 19.2 radial bearing sized 49.212 x 104.775 x 36.512 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 49.212 mm |
| Outer diameter D | 104.775 mm |
| Width B | 36.512 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 153 kN |
| Basic static load rating C0 | 189 kN |
| Limiting speed (mechanical) | 3600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1520 g |
| Manufacturer designation | NTN 4T-HM807044/HM807010 |
| 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 | 1.937 in |
|---|---|
| Outer diameter D | 4.125 in |
| Width B | 1.437 in |
| ISO bore code | 44 |
| Radial section height (D−d)/2 | 27.8 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) | 61 of 148 |
| Bore above smallest 4t-inch-series size | 36.512 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| HM807044 | 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 HM807044-HM807010 model number is decoded
For an inch shaft of 49.212 mm carrying combined radial and thrust load, NTN lists 4T-HM807044/HM807010, a single-row 4T tapered roller set of 153 kN C and 189 kN C0 inside the 104.775 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — HM807044 sits in the heavy-medium HM family. Speed planning uses both catalogue columns: grease 3,600 r/min is the mechanical ceiling for 4T-HM807044/HM807010, oil 4,800 r/min with circulating oil — a 1,200 r/min margin at this size. The printed 153/189 kN ratings belong to the assembled HM807044+HM807010 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-HM807044/HM807010 run near 3,600 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.
Typical equipment & failure modes
Common applications
- agricultural tractor transmission and PTO shafts
- industrial gearboxes built to inch shafting
- construction-equipment pivot and wheel positions
- mining and quarry conveyor drive pulleys
Known failure patterns
- cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film
- cup creep and housing fretting when the cup seat is cut too loose for the rotating load
- flaking on one cone only when a bent shaft loads the O/X pair unevenly
- pressed-steel cage pocket wear from roller skid at light radial load and high speed
- indentation of the raceways by hard particles in an open, unsealed arrangement
Selection pitfalls — read before you substitute
- Hub and pinion positions of this 49.212 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM807044/HM807010.
- The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 49.212 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.
- An unloaded 4T-HM807044/HM807010 near 3,600 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.
- Inch and metric bores collide on paper — 49.212 mm is 1.937 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.
- Grease packs must leave free volume inside the 36.512 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,800 r/min raises temperature and destroys the setting.
- The 153/189 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM807044/HM807010; 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-HM807044/HM807010?
4T-HM807044/HM807010 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 49.212 mm bore (1.937 in), 104.775 mm outside diameter and 36.512 mm assembled width T (4.125 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 189 kN, grease limiting speed 3,600 r/min, oil speed 4,800 r/min, mass about 1520 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-HM807044/HM807010 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the HM807044 cone or the HM807010 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 153/189 kN ratings change with the cup.
What is the difference between 4T-HM807044/HM807010 and a metric ISO 355 tapered bearing?
4T-HM807044/HM807010 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 49.212×104.775×36.512 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-HM807044/HM807010 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 HM807044/HM807010 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-HM807044/HM807010 list two speeds, 3,600 and 4,800 r/min?
The lower figure, 3,600 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-HM807044/HM807010 at 4,800 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.