32944E1 bearing: complete specifications & equivalents
The 32944E1 is a ISO 355 radial bearing sized 220 x 300 x 51 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 220 mm |
| Outer diameter D | 300 mm |
| Width B | 51 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 385 kN |
| Basic static load rating C0 | 670 kN |
| Fatigue load limit Pu | 61 kN |
| Limiting speed (mechanical) | 1000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 9470 g |
| Manufacturer designation | NTN 32944E1 |
| Standard | ISO 355 |
| Catalog version | NTN Ball and Roller Bearings CAT.No.2203E |
| Last verified | 2026-10-01 |
Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203E) · extracted 2026-10-01
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203E); 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 & 32900-series range
| Bore d | 8.661 in |
|---|---|
| Outer diameter D | 11.811 in |
| Width B | 2.008 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 40 mm |
| Smallest bore in 32900-series | 35 mm |
| Largest outer diameter in 32900-series | 600 mm |
| Width range across 32900-series | 14–100 mm |
| Bore position in 32900-series (smallest first) | 26 of 37 |
| Bore above smallest 32900-series size | 185 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 32944E1 | 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 32944E1 model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32944E1 denotes the extra-light thin-section 32900 family of metric tapered roller bearings, 220 mm bore, 300 mm outside diameter and 51 mm assembled width T (8.661 × 11.811 × 2.008 in) to the ISO 355 boundary plan. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 220×300 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Grease relubrication at 1,000 r/min limiting speed targets the rib contact; if the drive needs 1,400 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. When pairing 32944E1 with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.
Typical equipment & failure modes
Common applications
- rolling-mill roll-neck and gearbox positions
- large crusher and SAG/AG-mill drive shafts
- wind-turbine gearbox and main-shaft arrangements
- offshore crane and drawworks drums
Known failure patterns
- cone-raceway spalling at the large rib when preload is set too high for the lubricant film
- flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft
- smearing on the roller large ends and cone rib after a dry start with preload but no oil film
- cage damage from a mounting blow delivered through the roller complement instead of the ring face
- false brinelling on a stationary paired set exposed to external vibration
Selection pitfalls — read before you substitute
- At 220 mm bore the 32944E1 set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 385 kN C level.
- The thin 51 mm section of 32944E1 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 220 mm bore smears the roller ends against the rib.
- Replacing one half of an adjusted pair without resetting end play negates the 51 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.
- On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 220 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.
- Replacing one half of an adjusted pair without resetting end play negates the 51 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.
- The 385/670 kN ratings and 61 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32944E1; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive.
Frequently asked questions
What are the dimensions and catalogue ratings of NTN 32944E1?
32944E1 is a metric 4T tapered roller bearing to ISO 355: 220 mm bore, 300 mm outside diameter and 51 mm assembled width T (8.661 × 11.811 × 2.008 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 385 kN, C0 670 kN, Pu 61 kN, grease limiting speed 1,000 r/min, oil speed 1,400 r/min, mass about 9470 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 32944E1?
4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32944E1); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 32944E1 designation encode the 220 mm bore?
last two digits E1 are the ISO bore code, ×5 = 220 mm (codes 00–03 use the 10/12/15/17 exception table). The 300 mm OD and 51 mm assembled T follow the ISO 355 dimension-series plan.
Why does 32944E1 list two speeds, 1,000 and 1,400 r/min?
The lower figure, 1,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32944E1 at 1,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 32944E1 mean?
It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN Ball and Roller Bearings CAT.No.2203E on 2026-10-01. Read our editorial & correction policy.