7340 bearing: complete specifications & equivalents
The 7340 is a ISO 15 radial bearing sized 200 x 420 x 80 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 200 mm |
| Outer diameter D | 420 mm |
| Width B | 80 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 500 kN |
| Basic static load rating C0 | 610 kN |
| Fatigue load limit Pu | 27 kN |
| Limiting speed (mechanical) | 1700 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 53100 g |
| Manufacturer designation | NTN 7340 |
| 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 | 7.874 in |
|---|---|
| Outer diameter D | 16.535 in |
| Width B | 3.15 in |
| ISO bore code | 40 |
| Radial section height (D−d)/2 | 110 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) | 32 of 32 |
| Bore above smallest 7300-series size | 190 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 7340-BCBM | SKF | 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 7340 model number is decoded
At 200 x 420 x 80 mm, NTN 7340 sits in the heavy-duty 7300 single-row family of the angular-contact programme. NTN builds the number from 73 is the single-row dimension series (heavy-duty 7300 single-row family), then 40 encodes the 200 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. NTN prints 500 kN dynamic and 610 kN static for this size and a 27 kN fatigue load limit Pu. 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. A 200 mm shaft typically takes a m6/n6 fit for rotating inner-ring load; keep the housing bore to G6/H6 class so the contact geometry is not distorted.
Typical equipment & failure modes
Common applications
- heavy industrial gearbox main shafts
- large fan, blower and turbo-compressor rotors
- rolling-mill backup and drive spindles
- crusher and mill pinion 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
- thermal runaway from excessive preload: the pair runs hot, grease darkens and the contact ellipse spreads until the raceways smear
- resin-cage cracking on the 7900-series sizes after hot, dry running or solvent attack on the polymer
- contamination-induced denting — hard particles rolled into the contact ellipse become the initiation points for surface fatigue
- flaking that starts at the raceway shoulder on the thrust-loaded side when axial load repeatedly exceeds the design share
Selection pitfalls — read before you substitute
- At this size the shaft fit, shoulder geometry and preload procedure dominate the outcome; a 200 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.
- 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.
- Grease rated for deep-groove motor duty is not automatically right at 1,700 r/min with preload; check the grease speed factor against the catalogue figure.
- Never use a four-point or double-row bearing as a like-for-like swap for a single 7340 without re-checking axial float, heat and housing width — the kinematics differ.
- The 500/610 kN ratings and 27 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 7340; 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 7340?
7340 is a single-row angular contact ball bearing to ISO 15: 200 mm bore, 420 mm outside diameter, 80 mm width (7.874 x 16.535 x 3.15 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 500 kN, C0 610 kN and a 27 kN fatigue load limit Pu; the grease limiting speed is 1,700 r/min and the oil rating 2,200 r/min; mass about 53100 g.
How is the 7340 designation structured?
73 is the single-row dimension series (heavy-duty 7300 single-row family); 40 encodes the 200 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 420 mm OD and 80 mm width follow the ISO 15 boundary-dimension plan for that series.
Which axial direction does 7340 support?
One 7340 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 7340?
Per NTN Ball and Roller Bearings CAT.No.2203E, the grease limiting speed is 1,700 r/min and the oil rating 2,200 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 7340?
The 200/420/80 mm envelope is ISO 15 interchangeable, but internal geometry — contact angle, osculation, cage and shoulder details — is maker-specific. Re-verify C 500 kN / C0 610 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.