81212-TN bearing: complete specifications & equivalents
The 81212-TN is a ISO 104 radial bearing sized 60 x 95 x 26 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 60 mm |
| Outer diameter D | 95 mm |
| Width B | 26 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | polymer (PA66 glass-fibre reinforced) |
| Basic dynamic load rating C | 137 kN |
| Basic static load rating C0 | 465 kN |
| Fatigue load limit Pu | 47.5 kN |
| Reference speed (thermal) | 1400 rpm |
| Limiting speed (mechanical) | 2800 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 650 g |
| Manufacturer designation | 81212 TN |
| Standard | ISO 104 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings |
| Last verified | 2026-09-27 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings) · extracted 2026-09-27
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings); 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 & 81200-series range
| Bore d | 2.362 in |
|---|---|
| Outer diameter D | 3.74 in |
| Width B | 1.024 in |
| ISO bore code | 12 |
| Radial section height (D−d)/2 | 17.5 mm |
| Smallest bore in 81200-series | 30 mm |
| Largest outer diameter in 81200-series | 420 mm |
| Width range across 81200-series | 16–95 mm |
| Bore position in 81200-series (smallest first) | 7 of 28 |
| Bore above smallest 81200-series size | 30 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the 81212-TN model number is decoded
The heavy 812 series bearing 81212 TN carries pure axial load at low to moderate speed: 137 kN dynamic and 465 kN static across a 60×95 mm washer pair, 26 mm overall height. Reading the code: the first three digits 812 give the dimension series (heavy 812 series), the last two 12 encode the 60 mm shaft washer bore (code 12 × 5), and TN names the cage execution. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the glass fibre reinforced PA66 TN cage is standard for this size. The 650 g mass and 26 mm axial height sit between 60 and 95 mm washer diameters; check the seat shoulder spans the full ring face — a narrow shoulder causes washer fretting long before fatigue does. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.
Typical equipment & failure modes
Common applications
- extruder and injection press screw thrust blocks at low speed
- rolling-mill screwdown mechanisms and press adjusters
- slewing and turntable pivots with predominantly axial force
- crane hook crossheads carrying pure hook thrust while the hook swivels
Known failure patterns
- cage wear from rollers being dragged through unloaded zones under fluctuating thrust
- housing-washer rotation scored into an unmachined or loose seating face
- oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips
- false brinelling and rust-red witness marks on standby machines under external vibration
- roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)
Selection pitfalls — read before you substitute
- At 60 mm bore the minimum load (A 0.017) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.
- Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.
- Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81212 TN need different minimum load and lubrication despite the shared 60×95 mm outline.
- The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81212 TN size.
- the 1,400 r/min reference speed is the thermal criterion under load, the 2,800 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.
- The 137/465 kN ratings and 650 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only.
Frequently asked questions
Can a thrust ball bearing replace the 81212 TN?
They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting.
What ruins a 81212 TN in service?
Unloaded running below factor A 0.017 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 2,800 r/min limiting.
Which dimensions does the 81212 TN have?
A 81212 TN measures 60 mm bore × 95 mm outside diameter × 26 mm width (2.362 × 3.74 × 1.024 in). From SKF catalogue PUB BU/P1 17000: dynamic C 137 kN, static C0 465 kN, fatigue limit Pu 47.5 kN, reference speed 1,400 r/min, limiting speed 2,800 r/min, mass about 650 g. Raceway diameters Ea 64 mm / Eb 91 mm and minimum load factor A 0.017 guide the seat design.
What is the difference between 811 and 812 series?
811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81212 TN belongs to the heavy 812 series, 60×95×26 mm.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings on 2026-09-27. Read our editorial & correction policy.