7930 bearing: complete specifications & equivalents
The 7930 is a ISO 15 radial bearing sized 150 x 210 x 28 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 150 mm |
| Outer diameter D | 210 mm |
| Width B | 28 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 108 kN |
| Basic static load rating C0 | 117 kN |
| Fatigue load limit Pu | 5.8 kN |
| Limiting speed (mechanical) | 3100 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2960 g |
| Manufacturer designation | NTN 7930 |
| 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 & 7900-series range
| Bore d | 5.906 in |
|---|---|
| Outer diameter D | 8.268 in |
| Width B | 1.102 in |
| ISO bore code | 30 |
| Radial section height (D−d)/2 | 30 mm |
| Smallest bore in 7900-series | 25 mm |
| Largest outer diameter in 7900-series | 420 mm |
| Width range across 7900-series | 9–56 mm |
| Bore position in 7900-series (smallest first) | 22 of 32 |
| Bore above smallest 7900-series size | 125 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 7930 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the 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 7930 model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, 7930 appears as a extra-light, high-speed 7900 single-row family bearing of 150 mm bore, 210 mm outside diameter and 28 mm width. Two fields make up the code — 79 is the single-row dimension series (extra-light, high-speed 7900 single-row family) and 30 encodes the 150 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. On speed, the grease limiting speed is 3,100 r/min and the oil rating 4,100 r/min. Choose the extra-light, high-speed 7900 single-row family when the shaft needs a stiff locating support and the axial component is known to act mostly one way. Mount with the thrust against the marked face: the contact angle runs from the low shoulder of the inner ring to the high shoulder of the outer ring, and reversing it throws the capacity away.
Typical equipment & failure modes
Common applications
- rolling-mill backup and drive spindles
- crusher and mill pinion shafts
- large pump and turbine auxiliary shafts
- steel-plant conveyor and table roll drives
Known failure patterns
- false brinelling on the raceway contact ellipses when a preloaded spindle sits vibrating at standstill — visible as evenly spaced flute-like wear at ball pitch
- thermal runaway from excessive preload: the pair runs hot, grease darkens and the contact ellipse spreads until the raceways smear
- pressed-steel cage pocket wear and rivet loosening after repeated ball skid at light load and high speed
- current-erosion pitting on VFD-driven motor shafts, first visible as a grey frosted band across both raceways
- contamination-induced denting — hard particles rolled into the contact ellipse become the initiation points for surface fatigue
Selection pitfalls — read before you substitute
- At this size the shaft fit, shoulder geometry and preload procedure dominate the outcome; a 150 mm bore bearing forgives nothing in a poorly machined housing.
- The 7900 extra-light section is chosen for speed and stiffness, not for load margin — check that C0 117 kN really covers the worst static case before substituting it for a 7000.
- Grease rated for deep-groove motor duty is not automatically right at 3,100 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 7930 without re-checking axial float, heat and housing width — the kinematics differ.
- The C0 of 117 kN is a static rating, not a permissible running thrust — sizing continuous axial load from C0 alone is a recurring drawing-office error.
- The 108/117 kN ratings and 5.8 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 7930; 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 7930?
7930 is a single-row angular contact ball bearing to ISO 15: 150 mm bore, 210 mm outside diameter, 28 mm width (5.906 x 8.268 x 1.102 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 108 kN, C0 117 kN and a 5.8 kN fatigue load limit Pu; the grease limiting speed is 3,100 r/min and the oil rating 4,100 r/min; mass about 2960 g.
How is the 7930 designation structured?
79 is the single-row dimension series (extra-light, high-speed 7900 single-row family); 30 encodes the 150 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 210 mm OD and 28 mm width follow the ISO 15 boundary-dimension plan for that series.
Which axial direction does 7930 support?
One 7930 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 7930?
Per NTN Ball and Roller Bearings CAT.No.2203E, the grease limiting speed is 3,100 r/min and the oil rating 4,100 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 7930?
The 150/210/28 mm envelope is ISO 15 interchangeable, but internal geometry — contact angle, osculation, cage and shoulder details — is maker-specific. Re-verify C 108 kN / C0 117 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.