HM813842-HM813810 bearing: complete specifications & equivalents
The HM813842-HM813810 is a ANSI ABMA 19.2 radial bearing sized 63.5 x 127 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 | 63.5 mm |
| Outer diameter D | 127 mm |
| Width B | 36.512 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 181 kN |
| Basic static load rating C0 | 228 kN |
| Limiting speed (mechanical) | 2900 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2130 g |
| Manufacturer designation | NTN 4T-HM813842/HM813810 |
| 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 | 2.5 in |
|---|---|
| Outer diameter D | 5 in |
| Width B | 1.437 in |
| ISO bore code | 42 |
| Radial section height (D−d)/2 | 31.8 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) | 81 of 148 |
| Bore above smallest 4t-inch-series size | 50.8 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| HM813842 | 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 HM813842-HM813810 model number is decoded
NTN supplies this 2.5 in (63.5 mm) shaft position as 4T-HM813842/HM813810: cone HM813842, cup HM813810, profiled rollers and a pressed-steel cage, rated 181 kN basic dynamic and 228 kN static. 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 — HM813842 sits in the heavy-medium HM family. Selection: C 181 kN against C0 228 kN gives a C0/C ratio of 1.26 for the 63.5 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for HM813810: within the heavy-medium HM family tables the HM813842 cone is listed against several cup options, and it is the cup that fixes the 127 mm OD and the 36.512 mm assembled width — quote the full HM813842/HM813810 pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 63.5 mm pair is misadjusted and the set will edge-load in service.
Typical equipment & failure modes
Common applications
- crusher and screening-plant eccentric shafts
- heavy truck and bus drive-axle differentials
- plant gearboxes on inch-dimensioned shaft lines
- large conveyor head pulleys in bulk-handling plant
Known failure patterns
- rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries
- 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
- 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 63.5 mm cone by induction heating (max 120 °C) and the 127 mm cup with a press sleeve; at 2130 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 63.5 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.
- An unloaded 4T-HM813842/HM813810 near 2,900 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.
- Replacing one half of an adjusted pair without resetting end play negates the 36.512 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.
- Quote the full HM813842/HM813810 pair at ordering: the HM813842 cone also ships against sibling cups, and a cup from another reference changes the 36.512 mm assembled width and the rating.
- The 181/228 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM813842/HM813810; 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-HM813842/HM813810?
4T-HM813842/HM813810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 127 mm outside diameter and 36.512 mm assembled width T (5 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 181 kN, C0 228 kN, grease limiting speed 2,900 r/min, oil speed 3,800 r/min, mass about 2130 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-HM813842/HM813810 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the HM813842 cone or the HM813810 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 181/228 kN ratings change with the cup.
What is the difference between 4T-HM813842/HM813810 and a metric ISO 355 tapered bearing?
4T-HM813842/HM813810 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 63.5×127×36.512 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-HM813842/HM813810 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 HM813842/HM813810 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-HM813842/HM813810 list two speeds, 2,900 and 3,800 r/min?
The lower figure, 2,900 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-HM813842/HM813810 at 3,800 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.