7018-NTN bearing: complete specifications & equivalents
The 7018-NTN is a ISO 15 radial bearing sized 90 x 140 x 24 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 90 mm |
| Outer diameter D | 140 mm |
| Width B | 24 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 72 kN |
| Basic static load rating C0 | 63.5 kN |
| Fatigue load limit Pu | 4.15 kN |
| Limiting speed (mechanical) | 4900 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1350 g |
| Manufacturer designation | NTN 7018 |
| 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 & 7000-series range
| Bore d | 3.543 in |
|---|---|
| Outer diameter D | 5.512 in |
| Width B | 0.945 in |
| ISO bore code | 18 |
| Radial section height (D−d)/2 | 25 mm |
| Smallest bore in 7000-series | 10 mm |
| Largest outer diameter in 7000-series | 420 mm |
| Width range across 7000-series | 8–65 mm |
| Bore position in 7000-series (smallest first) | 19 of 36 |
| Bore above smallest 7000-series size | 80 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 7018 | GENERIC-ISO | full Dimensions and internal design equivalent — standard interchange. | Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier. |
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 7018-NTN model number is decoded
7018 is the 90 mm bore member of NTN's standard-section 7000 single-row family, with a 140 mm outside diameter and 24 mm section width. The designation breaks down as 70 is the single-row dimension series (standard-section 7000 single-row family); 18 encodes the 90 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 1350 g, which at this 25.0 mm radial section keeps the bearing comfortably inside high-speed spindle weight budgets. Selection starts from the thrust share: as axial load grows past roughly half the radial load, an angular-contact position of this section usually outlives a deep-groove one. Shaft and housing shoulders must clear the ring corners yet support enough face — the catalogue abutment diameters for the 90 mm bore give the working limits.
Typical equipment & failure modes
Common applications
- marine auxiliary and winch gearbox shafts
- rolling-mill and metalworking drive shafts
- large pump, fan and compressor rotor shafts
- crane and hoist gearbox shafts
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
- loss of preload after housing-fret or shaft creep, leaving the pair loose — ball skidding, cage rattle and a falling natural frequency follow
- resin-cage cracking on the 7900-series sizes after hot, dry running or solvent attack on the polymer
- edge loading and early spalling from housing bores that are out of round or shoulders that are too small for the ring face
- lubricant starvation scoring at the ball/raceway contact when grease volume or relubrication interval is guessed instead of calculated
Selection pitfalls — read before you substitute
- Bearings of 90 mm bore arrive heavy enough that handling damage (dents from slings, tilting on the shaft) is a real failure precursor — use proper lifting and heating kit.
- 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.
- Grease rated for deep-groove motor duty is not automatically right at 4,900 r/min with preload; check the grease speed factor against the catalogue figure.
- Grease rated for deep-groove motor duty is not automatically right at 4,900 r/min with preload; check the grease speed factor against the catalogue figure.
- 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 72/63.5 kN ratings and 4.15 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 7018; 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 7018?
7018 is a single-row angular contact ball bearing to ISO 15: 90 mm bore, 140 mm outside diameter, 24 mm width (3.543 x 5.512 x 0.945 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 72 kN, C0 63.5 kN and a 4.15 kN fatigue load limit Pu; the grease limiting speed is 4,900 r/min and the oil rating 6,500 r/min; mass about 1350 g.
How is the 7018 designation structured?
70 is the single-row dimension series (standard-section 7000 single-row family); 18 encodes the 90 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 140 mm OD and 24 mm width follow the ISO 15 boundary-dimension plan for that series.
Which axial direction does 7018 support?
One 7018 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 7018?
Per NTN Ball and Roller Bearings CAT.No.2203E, the grease limiting speed is 4,900 r/min and the oil rating 6,500 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 7018?
The 90/140/24 mm envelope is ISO 15 interchangeable, but internal geometry — contact angle, osculation, cage and shoulder details — is maker-specific. Re-verify C 72 kN / C0 63.5 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.