SKF22211KW33Double-Row Spherical Roller Bearing 55 x 100 x 25 mm, 1:12 Tapered Bore, H311 Adapter Sleeve Mount, W33 Lubrication Groove, 1 Pc

Product Description

What this part is

A Torrington double-row spherical roller bearing, 55 mm bore x 100 mm outside diameter x 25 mm wide, in the ISO 222 dimension series, with a tapered bore. Two rows of barrel rollers run on one spherical outer raceway, so the inner ring and roller set swivel bodily inside the outer ring. That self-aligning action absorbs shaft deflection and housing misalignment that would destroy a cylindrical roller or deep groove ball bearing in the same envelope, while carrying very heavy radial load and thrust in both directions.

Decoding the designation

222 — double-row spherical roller bearing, dimension series 22.
11 — bore code for a 55 mm bore.
K — tapered bore, taper ratio 1:12. The character that decides how the bearing mounts.
W33 — annular lubrication groove around the outer ring plus three lubrication holes through it.

There is no clearance suffix in the base designation, so the bearing carries Normal (CN) radial internal clearance. The carton also carries the legacy Torrington designation 55SD22 and an F4 marking; both are retained on this listing as searchable alternates.

What these specs mean in practice — the tapered bore:
A 1:12 tapered bore does not fit a plain shaft. It has to be drawn up a matching taper, which means one of two accessories, neither of which is included with this bearing:

An H311 adapter sleeve, letting the bearing clamp anywhere along a plain 50 mm shaft. Note that the shaft is 50 mm and not 55 mm — the sleeve wall takes up the difference, and mis-reading that is the commonest ordering mistake on tapered-bore bearings. H-series adapter sleeves are normally supplied complete with their KM11 locknut and MB11 lockwasher.
An AHX311 withdrawal sleeve, where the bearing sits on a stepped 55 mm seat. Withdrawal sleeves come without a nut, ordered separately.

What you gain is direct control over internal clearance and the ability to mount a bearing anywhere along a length of plain round bar with no machined seat — which is exactly why conveyor and bulk-handling builders specify them. How far you draw the bearing up the sleeve sets how much the inner ring expands, and therefore the running clearance you finish with. Measure the clearance reduction as you tighten: over-driving preloads the bearing before it ever turns and is the classic way to kill one on commissioning, and under-driving leaves the inner ring free to creep on the sleeve.

The outer-ring groove and three holes let grease or oil be fed straight into the roller rows through the housing instead of relying on lubricant migrating in from the ends. Relubrication is the largest single factor in spherical roller bearing life, so on anything greased in service this feature matters — and it does need a housing with a lubrication port lined up on the groove.

Published ratings and mounting data

Timken, which absorbed Torrington in 2003, publishes the following for the 22211KEJW33 that succeeds this bearing:

Basic dynamic load rating C: 140 000 N (31 400 lbf)
Basic static load rating C0: 142 000 N (31 900 lbf)
Thermal reference speed: 5 800 rpm on oil, 4 700 rpm on grease
Mass: approximately 0.81 kg
Adapter sleeve: H311, for a 50 mm shaft
Withdrawal sleeve: AHX311, for a 55 mm seat

Those speeds are thermal reference figures, not limiting speeds. Timken rates this family thermally rather than kinematically, so do not compare the numbers directly against an SKF or FAG limiting speed for the same size — they are measuring different things, and the thermal figure will always look lower.

Quantity and configuration

Sold as 1 Pc. One complete bearing: inner ring with both roller rows and cage, plus the outer ring. Spherical roller bearings are a non-separable assembly, so there is no cup or cone to buy alongside. This is the bare bearing only — no adapter sleeve, withdrawal sleeve, locknut, lockwasher or housing is included, and a sleeve is required to mount it.

Fitting notes

Slide the sleeve onto the shaft, fit the bearing onto the sleeve taper, then draw it up with the locknut while measuring the reduction in radial internal clearance with a feeler gauge across the unloaded roller row. Work to the published clearance-reduction figure rather than to a torque value, because the taper turns small axial travel into large radial expansion and torque alone tells you very little. Bend one lockwasher tab into the nut slot once you are satisfied. Seat the outer ring squarely in its housing and let it take up its own alignment before final tightening; clamping the outer ring off-neutral throws away the self-aligning capability. Align the housing lubrication port with the outer-ring groove and purge before the first run. A plain shaft seat at h9 is generally adequate under an adapter sleeve.

Interchange guidance

Torrington’s bearing business went to Timken in February 2003, so the current-catalogue successor is Timken 22211KEJW33. Other dimensionally equivalent tapered-bore 22211 bearings include SKF 22211 EK, FAG 22211-E1-XL-K, NSK 22211EAKE4, NTN 22211EAKW33, NTN-SNR 22211EAKW33, RHP 22211EKJW33 and Link-Belt 22211LBK. All of them mount on the same H311 adapter sleeve, because H-series sleeve dimensions follow ISO 2982-1 and DIN 5415 rather than any one maker’s standard, so sleeves interchange freely across brands. Read the lubrication codes as one feature under different letters: W33 on Timken, SKF, RHP and Link-Belt, E4 on NSK, S on FAG, D1 on NTN Japan, B33 on legacy SNR. Two traps — SKF W alone means the groove and holes are absent, and the straight-bore 22211 is a related size, not an interchange: same envelope, but it mounts directly on a 55 mm shaft and this bearing will not.