7907 bearing: complete specifications & equivalents
The 7907 is a ISO 15 radial bearing sized 35 x 55 x 10 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 35 mm |
| Outer diameter D | 55 mm |
| Width B | 10 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | polymer (PA66 glass-fibre reinforced) |
| Basic dynamic load rating C | 13.3 kN |
| Basic static load rating C0 | 8.85 kN |
| Fatigue load limit Pu | 0.64 kN |
| Limiting speed (mechanical) | 13000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 88 g |
| Manufacturer designation | NTN 7907 |
| 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 | 1.378 in |
|---|---|
| Outer diameter D | 2.165 in |
| Width B | 0.394 in |
| ISO bore code | 07 |
| Radial section height (D−d)/2 | 10 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) | 3 of 32 |
| Bore above smallest 7900-series size | 10 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 7907 | 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 7907 model number is decoded
From the extra-light, high-speed 7900 single-row family, 7907 measures 35 mm across the bore, 55 mm over the outer ring and 10 mm across the faces. Decoding 7907: 79 is the single-row dimension series (extra-light, high-speed 7900 single-row family), with 07 encodes the 35 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. With C 13.3 kN and C0 8.85 kN, each mm of bore carries about 0.38 kN of dynamic rating. Against a deep-groove bearing of the same 35 mm bore, this bearing trades some pure-radial comfort for real one-direction thrust capacity and higher running accuracy. A 35 mm shaft typically takes a k5/m5 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
- printing-press cylinder and folder shafts
- machine-tool spindle cartridges and driven tooling
- industrial pump and blower impeller shafts
- gearbox input shafts under helical-gear thrust
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
- current-erosion pitting on VFD-driven motor shafts, first visible as a grey frosted band across both raceways
- 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 35 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 8.85 kN really covers the worst static case before substituting it for a 7000.
- The C0 of 8.85 kN is a static rating, not a permissible running thrust — sizing continuous axial load from C0 alone is a recurring drawing-office error.
- 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 35 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.
- The 13.3/8.85 kN ratings and 0.64 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 7907; 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 7907?
7907 is a single-row angular contact ball bearing to ISO 15: 35 mm bore, 55 mm outside diameter, 10 mm width (1.378 x 2.165 x 0.394 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 13.3 kN, C0 8.85 kN and a 0.64 kN fatigue load limit Pu; the grease limiting speed is 13,000 r/min and the oil rating 17,000 r/min; mass about 88 g.
How is the 7907 designation structured?
79 is the single-row dimension series (extra-light, high-speed 7900 single-row family); 07 encodes the 35 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 55 mm OD and 10 mm width follow the ISO 15 boundary-dimension plan for that series.
Which axial direction does 7907 support?
One 7907 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 7907?
Per NTN Ball and Roller Bearings CAT.No.2203E, the grease limiting speed is 13,000 r/min and the oil rating 17,000 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 7907?
The 35/55/10 mm envelope is ISO 15 interchangeable, but internal geometry — contact angle, osculation, cage and shoulder details — is maker-specific. Re-verify C 13.3 kN / C0 8.85 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.