7910 bearing: complete specifications & equivalents
The 7910 is a ISO 15 radial bearing sized 50 x 72 x 12 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 50 mm |
| Outer diameter D | 72 mm |
| Width B | 12 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | polymer (PA66 glass-fibre reinforced) |
| Basic dynamic load rating C | 18.4 kN |
| Basic static load rating C0 | 14.5 kN |
| Fatigue load limit Pu | 0.98 kN |
| Limiting speed (mechanical) | 9200 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 157 g |
| Manufacturer designation | NTN 7910 |
| 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 | 1.969 in |
|---|---|
| Outer diameter D | 2.835 in |
| Width B | 0.472 in |
| ISO bore code | 10 |
| Radial section height (D−d)/2 | 11 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) | 6 of 32 |
| Bore above smallest 7900-series size | 25 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 7910 | 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 7910 model number is decoded
NTN 7910 belongs to the extra-light, high-speed 7900 single-row family: the catalogue boundary dimensions read 50 / 72 / 12 mm (bore / OD / width). Decoding 7910: 79 is the single-row dimension series (extra-light, high-speed 7900 single-row family), with 10 encodes the 50 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. Because the contact line is angled, one bearing of this type takes radial load plus thrust from one direction only — the opposite direction needs a second bearing or a matched set. Size selection is usually finished by checking that the C0 of 14.5 kN covers the maximum static or shock condition with the catalogue safety factor, not only the running load. Set preload or end-play with the pair as a unit and lock the adjustment; a single angular-contact bearing cannot run free like a deep-groove one.
Typical equipment & failure modes
Common applications
- machine-tool spindle cartridges and driven tooling
- industrial pump and blower impeller shafts
- gearbox input shafts under helical-gear thrust
- electric motor shafts with axial locating duty
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
- resin-cage cracking on the 7900-series sizes after hot, dry running or solvent attack on the polymer
- flaking that starts at the raceway shoulder on the thrust-loaded side when axial load repeatedly exceeds the design share
- current-erosion pitting on VFD-driven motor shafts, first visible as a grey frosted band across both raceways
Selection pitfalls — read before you substitute
- In this size class the common miss is lubrication interval, not fit — a 50 mm spindle at the catalogue speeds needs a calculated relubrication plan, not a calendar one.
- The 7900 extra-light section is chosen for speed and stiffness, not for load margin — check that C0 14.5 kN really covers the worst static case before substituting it for a 7000.
- The 9,200 r/min speed figure assumes the catalogue lubrication state and a correctly set pair; real limits drop fast with excess grease fill or heavy preload.
- The C0 of 14.5 kN is a static rating, not a permissible running thrust — sizing continuous axial load from C0 alone is a recurring drawing-office error.
- The 9,200 r/min speed figure assumes the catalogue lubrication state and a correctly set pair; real limits drop fast with excess grease fill or heavy preload.
- The 18.4/14.5 kN ratings and 0.98 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 7910; 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 7910?
7910 is a single-row angular contact ball bearing to ISO 15: 50 mm bore, 72 mm outside diameter, 12 mm width (1.969 x 2.835 x 0.472 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 18.4 kN, C0 14.5 kN and a 0.98 kN fatigue load limit Pu; the grease limiting speed is 9,200 r/min and the oil rating 12,000 r/min; mass about 157 g.
How is the 7910 designation structured?
79 is the single-row dimension series (extra-light, high-speed 7900 single-row family); 10 encodes the 50 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 72 mm OD and 12 mm width follow the ISO 15 boundary-dimension plan for that series.
Which axial direction does 7910 support?
One 7910 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 7910?
Per NTN Ball and Roller Bearings CAT.No.2203E, the grease limiting speed is 9,200 r/min and the oil rating 12,000 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 7910?
The 50/72/12 mm envelope is ISO 15 interchangeable, but internal geometry — contact angle, osculation, cage and shoulder details — is maker-specific. Re-verify C 18.4 kN / C0 14.5 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.