7326 bearing: complete specifications & equivalents
The 7326 is a ISO 15 radial bearing sized 130 x 280 x 58 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 130 mm |
| Outer diameter D | 280 mm |
| Width B | 58 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 305 kN |
| Basic static load rating C0 | 293 kN |
| Fatigue load limit Pu | 16 kN |
| Limiting speed (mechanical) | 2700 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 17600 g |
| Manufacturer designation | NTN 7326 |
| Standard | ISO 15 |
| 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 & 7300-series range
| Bore d | 5.118 in |
|---|---|
| Outer diameter D | 11.024 in |
| Width B | 2.283 in |
| ISO bore code | 26 |
| Radial section height (D−d)/2 | 75 mm |
| Smallest bore in 7300-series | 10 mm |
| Largest outer diameter in 7300-series | 420 mm |
| Width range across 7300-series | 11–80 mm |
| Bore position in 7300-series (smallest first) | 25 of 32 |
| Bore above smallest 7300-series size | 120 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 7326-BCBM | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 130×280×58 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
| 7326-BM | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 130×280×58 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
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 7326 model number is decoded
At 130 x 280 x 58 mm, NTN 7326 sits in the heavy-duty 7300 single-row family of the angular-contact programme. Reading the code: 73 is the single-row dimension series (heavy-duty 7300 single-row family), 26 encodes the 130 mm bore (bore code x 5); with no letter after the digits it is the standard 30 deg contact-angle execution — the 40 deg version carries a B. Catalogue mass is about 17600 g, which at this 75.0 mm radial section keeps the bearing comfortably inside high-speed spindle weight budgets. The 130/280/58 envelope is an ISO 15 boundary plan, so dimensional interchange with other makers holds — ratings and internal geometry do not automatically follow. After mounting, check axial float or preload with a dial gauge on the shaft end — the specification, not hand feel, decides whether the contact angle works as rated.
Typical equipment & failure modes
Common applications
- crusher and mill pinion shafts
- large pump and turbine auxiliary shafts
- steel-plant conveyor and table roll drives
- wind-turbine and heavy-machinery auxiliaries
Known failure patterns
- impact brinelling dents on the 30 deg contact path after a shaft-side hammer blow during mounting, because axial shock travels straight through the contact angle
- thermal runaway from excessive preload: the pair runs hot, grease darkens and the contact ellipse spreads until the raceways smear
- machined-cage land scoring when a high-speed spindle runs past its grease rating and the cage runs dry on its guidance surface
- edge loading and early spalling from housing bores that are out of round or shoulders that are too small for the ring face
- edge loading and early spalling from housing bores that are out of round or shoulders that are too small for the ring face
Selection pitfalls — read before you substitute
- At this size the shaft fit, shoulder geometry and preload procedure dominate the outcome; a 130 mm bore bearing forgives nothing in a poorly machined housing.
- The standard 30 deg bearing and its B (40 deg) sibling share the envelope; picking between them is a load-direction decision, not a quality upgrade.
- A single-row angular contact left loose on the shaft to "help assembly" will fret the seat: the contact angle keeps driving the ring axially under load.
- On a 130 mm shaft, an interference fit eats internal clearance; skipping the clearance/preload recalculation is the classic cause of a new bearing running 20 deg C hotter than the drawing suggests.
- If the application vibrates at standstill (transport, idle machine next to a running line), specify protection: the contact ellipse of a preloaded bearing false-brinells faster than a loose one.
- The 305/293 kN ratings and 16 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 7326; internal geometry legitimately differs between manufacturers, so re-verify ratings, contact angle and suffix before substituting another make on a rated drive.
Frequently asked questions
What are the dimensions and catalogue ratings of NTN 7326?
7326 is a single-row angular contact ball bearing to ISO 15: 130 mm bore, 280 mm outside diameter, 58 mm width (5.118 x 11.024 x 2.283 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 305 kN, C0 293 kN and a 16 kN fatigue load limit Pu; the grease limiting speed is 2,700 r/min and the oil rating 3,600 r/min; mass about 17600 g.
How is the 7326 designation structured?
73 is the single-row dimension series (heavy-duty 7300 single-row family); 26 encodes the 130 mm bore (bore code x 5); with no letter after the digits it is the standard 30 deg contact-angle execution — the 40 deg version carries a B. The 280 mm OD and 58 mm width follow the ISO 15 boundary-dimension plan for that series.
Which axial direction does 7326 support?
One 7326 alone takes thrust in one direction only, along its 30 deg contact angle; reversing thrust calls for a second bearing or a factory-matched DB/DF/DT pair (the catalogue right-hand columns list the paired ratings). Radial load is always carried as a combined load through the angled contact.
What lubrication speeds does NTN print for 7326?
Per NTN Ball and Roller Bearings CAT.No.2203E, the grease limiting speed is 2,700 r/min and the oil rating 3,600 r/min. These are catalogue ceilings for a correctly mounted bearing with the stated lubricant; preload, fill quantity, ambient heat and paired arrangements all move the real limit.
What should be checked before substituting another make for 7326?
The 130/280/58 mm envelope is ISO 15 interchangeable, but internal geometry — contact angle, osculation, cage and shoulder details — is maker-specific. Re-verify C 305 kN / C0 293 kN, the speed figures, contact angle and suffix meaning against the donor catalogue before swapping on a rated drive.
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.