577-572 bearing: complete specifications & equivalents
The 577-572 is a ANSI ABMA 19.2 radial bearing sized 74.612 x 139.992 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 | 74.612 mm |
| Outer diameter D | 139.992 mm |
| Width B | 36.512 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 197 kN |
| Basic static load rating C0 | 265 kN |
| Limiting speed (mechanical) | 2600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2470 g |
| Manufacturer designation | NTN 4T-577/572 |
| 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 | 2.937 in |
|---|---|
| Outer diameter D | 5.511 in |
| Width B | 1.437 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 32.7 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) | 92 of 148 |
| Bore above smallest 4t-inch-series size | 61.91199999999999 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 577 | 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 577-572 model number is decoded
NTN supplies this 2.937 in (74.612 mm) shaft position as 4T-577/572: cone 577, cup 572, profiled rollers and a pressed-steel cage, rated 197 kN basic dynamic and 265 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 577/572 without it. Imperial cross-check for the drawing: 74.612×139.992×36.512 mm converts to 2.937 × 5.511 × 1.437 in; the ABMA envelope swaps with like-numbered inch parts but the 197/265 kN ratings are NTN-specific. Cup-side note for 572: within the pure-numeric inch family tables the 577 cone is listed against several cup options, and it is the cup that fixes the 139.992 mm OD and the 36.512 mm assembled width — quote the full 577/572 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-577/572 run near 2,600 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.
Typical equipment & failure modes
Common applications
- plant gearboxes on inch-dimensioned shaft lines
- large conveyor head pulleys in bulk-handling plant
- paper-machine and calender roll supports
- off-highway and forestry machine axles
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
- rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load
Selection pitfalls — read before you substitute
- Mount the 74.612 mm cone by induction heating (max 120 °C) and the 139.992 mm cup with a press sleeve; at 2470 g a cocked ring brinells the raceway directly.
- The pure-numeric inch family at 74.612 mm bore (139.992×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 577/572 reference at purchase.
- Do not confuse T (36.512 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.
- Shaft and housing fillets must clear the ring chamfers of 577 and 572; use undercut shoulders so the rings seat on the face, not on a radius.
- Fit selection follows the rotating ring: a rotating cone on a 74.612 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.
- The 197/265 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-577/572; 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-577/572?
4T-577/572 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 74.612 mm bore (2.937 in), 139.992 mm outside diameter and 36.512 mm assembled width T (5.511 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 197 kN, C0 265 kN, grease limiting speed 2,600 r/min, oil speed 3,400 r/min, mass about 2470 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-577/572 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the 577 cone or the 572 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 197/265 kN ratings change with the cup.
What is the difference between 4T-577/572 and a metric ISO 355 tapered bearing?
4T-577/572 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 74.612×139.992×36.512 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-577/572 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 577/572 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-577/572 list two speeds, 2,600 and 3,400 r/min?
The lower figure, 2,600 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-577/572 at 3,400 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.