126-TN9 bearing: complete specifications & equivalents
The 126-TN9 is a ISO 15 radial bearing sized 6 x 19 x 6 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 6 mm |
| Outer diameter D | 19 mm |
| Width B | 6 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | polymer (PA66 glass-fibre reinforced) |
| Basic dynamic load rating C | 2.51 kN |
| Basic static load rating C0 | 0.48 kN |
| Fatigue load limit Pu | 0.025 kN |
| Reference speed (thermal) | 70000 rpm |
| Limiting speed (mechanical) | 45000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 9 g |
| Manufacturer designation | 126 TN9 |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018) |
| Last verified | 2026-09-27 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-27
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018)); SKF® and SKF Explorer® are trademarks of AB SKF, used here for identification only — mpnbase is not an authorized SKF distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at skf.com.
Dimensions in inches & 1200-series range
| Bore d | 0.236 in |
|---|---|
| Outer diameter D | 0.748 in |
| Width B | 0.236 in |
| ISO bore code | 26 |
| Radial section height (D−d)/2 | 6.5 mm |
| Smallest bore in 1200-series | 6 mm |
| Largest outer diameter in 1200-series | 230 mm |
| Width range across 1200-series | 6–154 mm |
| Bore position in 1200-series (smallest first) | 1 of 32 |
| Bore above smallest 1200-series size | 0 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the 126-TN9 model number is decoded
The 12xx series is the light/normal-section self-aligning ball bearing (ISO dimension series 02). the final digit of 126 is the bore in millimetres: 126 TN9 fits a 6 mm shaft (direct miniature spelling). Envelope 6×19×6 mm (0.236×0.748×0.236 in) with a 6.5 mm radial section height, C 2.51 kN, C0 0.48 kN and Pu 0.025 kN. The open 126 TN9 carries no shields or seals and relies on application lubrication and external sealing. The TN9 suffix identifies the glass-fibre-reinforced polyamide 66 cage execution. The bore is cylindrical (straight), for a press-fit on a 6 mm shaft. Reference (thermal) speed 70000 r/min, limiting speed 45000 r/min, catalogue mass 9 g.
Typical equipment & failure modes
Common applications
- conveyor idler rollers
- agricultural machinery shafts
- textile spindles and looms
- fan and blower shafts
Known failure patterns
- contamination wear when the open arrangement is used without adequate external sealing
- lubricant starvation where no regreasing interval is maintained
- raceway smearing under marginal lubrication at start-up
- electrical pitting in VFD-driven motors without shaft grounding
Selection pitfalls — read before you substitute
- Catalogue ratings for 126-TN9 (C 2.51 kN, C0 0.48 kN) are SKF figures from PUB BU/P1 17000; geometry revisions can change ratings without changing the designation, so keep the catalogue edition with the specification.
- The fatigue load limit is 0.025 kN; it feeds the equivalent-mean-load check, not the basic life calculation — do not substitute one for the other.
- The TN9 suffix on 126-TN9 denotes a glass-fibre-reinforced polyamide 66 cage: quiet and light at the 45000 r/min limiting speed, but it softens above roughly 120 °C — check the oil temperature in hot drives.
- Mount 126-TN9 by heating the inner ring (max 120 °C) on a cylindrical bore — driving it home through the outer ring or balls brinells the raceways.
- The fatigue load limit is 0.025 kN; it feeds the equivalent-mean-load check, not the basic life calculation — do not substitute one for the other.
- At 6 mm bore, C3 clearance is the safe choice when interference fits plus temperature rise consume the CN clearance; a hot tight bearing with no residual clearance fails fast.
Frequently asked questions
What are the dimensions of 126-TN9?
SKF 126 TN9 measures 6 mm bore × 19 mm OD × 6 mm width (0.236 × 0.748 × 0.236 in), mass about 9 g. It is open, with no shields or seals.
How do I read the 126 designation?
Miniature self-aligning bearings print the bore as the final digit, so 126 is a 6 mm bearing; the leading digits give the section family.
What is the speed rating of 126-TN9?
SKF lists a 70000 r/min thermal reference speed and a 45000 r/min mechanical limiting speed for 126 TN9; real limits also depend on lubrication and fits.
How much misalignment can 126-TN9 tolerate?
Self-aligning ball bearings tolerate roughly 2–3° of static misalignment for open executions; sealed 2RS1 variants like 126-TN9 allow less (about 1°) because the seal lip binds first.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-27. Read our editorial & correction policy.