81222-TN bearing: complete specifications & equivalents
The 81222-TN is a ISO 104 radial bearing sized 110 x 160 x 38 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 110 mm |
| Outer diameter D | 160 mm |
| Width B | 38 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | polymer (PA66 glass-fibre reinforced) |
| Basic dynamic load rating C | 260 kN |
| Basic static load rating C0 | 1000 kN |
| Fatigue load limit Pu | 98 kN |
| Reference speed (thermal) | 850 rpm |
| Limiting speed (mechanical) | 1700 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2300 g |
| Manufacturer designation | 81222 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 | 4.331 in |
|---|---|
| Outer diameter D | 6.299 in |
| Width B | 1.496 in |
| ISO bore code | 22 |
| Radial section height (D−d)/2 | 25 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) | 15 of 28 |
| Bore above smallest 81200-series size | 80 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the 81222-TN model number is decoded
81222 TN is a single-direction cylindrical roller thrust bearing to ISO 104 in the heavy 812 series: a flat shaft washer, a roller-and-cage set and a housing washer stacked to 110×160×38 mm, listed in SKF catalogue PUB BU/P1 17000 ch. 11.1. The designation 81222 TN states 812 series, 110 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. Rigid washers mean no self-alignment: the shaft and housing shoulders must be square and parallel to within the catalogue seat tolerances, or the rollers edge-load across the 38 mm height. Speed planning separates the 850 r/min thermal reference from the 1,700 r/min mechanical limiting speed. Thrust bearings govern the thermal speed of many vertical arrangements, and oil circulation raises the usable speed substantially above grease values. Mounting: locate the shaft washer on the 110 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 160 mm bore, and check the stack can tilt freely before clamping.
Typical equipment & failure modes
Common applications
- screw jack and lifting screw thrust positions under slow, steady load
- vertical electric motor and pump shafts whose rotor weight loads one bearing
- extruder and injection press screw thrust blocks at low speed
- rolling-mill screwdown mechanisms and press adjusters
Known failure patterns
- smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established
- shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder
- oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips
- hard-particle indentation where oil or grease filtration is inadequate
- cage wear from rollers being dragged through unloaded zones under fluctuating thrust
Selection pitfalls — read before you substitute
- At 110 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 38 mm.
- Factor A 0.08 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most "mysterious" early thrust failures are unloaded running.
- 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 81222 TN need different minimum load and lubrication despite the shared 110×160 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 81222 TN size.
- The 260/1000 kN ratings and 2300 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); 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
How should a 81222 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 0.08 minimum load is present.
What are the dimensions and ratings of the 81222 TN?
A 81222 TN measures 110 mm bore × 160 mm outside diameter × 38 mm width (4.331 × 6.299 × 1.496 in). From SKF catalogue PUB BU/P1 17000: dynamic C 260 kN, static C0 1000 kN, fatigue limit Pu 98 kN, reference speed 850 r/min, limiting speed 1,700 r/min, mass about 2300 g. Raceway diameters Ea 117 mm / Eb 152 mm and minimum load factor A 0.08 guide the seat design.
How is the 81222 TN designation read?
The first three digits 812 give the dimension series (heavy 812 series); 22 encodes the 110 mm bore (code 22 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately.
Why does 81222 TN need a minimum axial load?
Below factor A 0.08 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts.
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.