81210-TN bearing: complete specifications & equivalents
The 81210-TN is a ISO 104 radial bearing sized 50 x 78 x 22 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 50 mm |
| Outer diameter D | 78 mm |
| Width B | 22 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | polymer (PA66 glass-fibre reinforced) |
| Basic dynamic load rating C | 91.5 kN |
| Basic static load rating C0 | 300 kN |
| Fatigue load limit Pu | 31 kN |
| Reference speed (thermal) | 1700 rpm |
| Limiting speed (mechanical) | 3400 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 360 g |
| Manufacturer designation | 81210 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 | 1.969 in |
|---|---|
| Outer diameter D | 3.071 in |
| Width B | 0.866 in |
| ISO bore code | 10 |
| Radial section height (D−d)/2 | 14 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) | 5 of 28 |
| Bore above smallest 81200-series size | 20 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the 81210-TN model number is decoded
81210 TN is the rigid-washer thrust solution for a 50 mm shaft: unlike ball thrust types, the line contact of cylindrical rollers gives 91.5 kN C within just 22 mm of axial space, per the ISO 104 plan. The designation 81210 TN states 812 series, 50 mm bore, glass fibre reinforced PA66 TN cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.0072. Static safety matters for shock duty: compare peak axial force against C0 300 kN with the application's static factor, since crane hooks and screw positions see their worst load at zero or low speed. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.0072) is present without clamping the rollers.
Typical equipment & failure modes
Common applications
- 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
- screw jack and lifting screw thrust positions under slow, steady load
Known failure patterns
- cage wear from rollers being dragged through unloaded zones under fluctuating thrust
- washer back-face fretting where the seat is too narrow to support the full ring face
- oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips
- electrical erosion of raceways on VFD-driven shafts without grounding or insulation
- roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)
Selection pitfalls — read before you substitute
- At 50 mm bore the minimum load (A 0.0072) 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.
- the 1,700 r/min reference speed is the thermal criterion under load, the 3,400 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.
- The 91.5/300 kN ratings assume flat, full-support washer seats; a housing face narrower than the 78 mm washer OD invalidates the rating through edge stress.
- 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 81210 TN need different minimum load and lubrication despite the shared 50×78 mm outline.
- The 91.5/300 kN ratings and 360 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 the 81210 TN take reversing thrust?
No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load.
How should a 81210 TN be mounted?
Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.0072 minimum load is present.
What are the dimensions and ratings of the 81210 TN?
A 81210 TN measures 50 mm bore × 78 mm outside diameter × 22 mm width (1.969 × 3.071 × 0.866 in). From SKF catalogue PUB BU/P1 17000: dynamic C 91.5 kN, static C0 300 kN, fatigue limit Pu 31 kN, reference speed 1,700 r/min, limiting speed 3,400 r/min, mass about 360 g. Raceway diameters Ea 53 mm / Eb 75 mm and minimum load factor A 0.0072 guide the seat design.
How is the 81210 TN designation read?
The first three digits 812 give the dimension series (heavy 812 series); 10 encodes the 50 mm bore (code 10 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately.
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.