NSK22212CDKE4C3Double-Row Spherical Roller Bearing 60 x 110 x 28 mm, 1:12 Tapered Bore, H312 Adapter Sleeve Mount, W33 Lubrication Groove, C3 Clearance, 1 Pc

Product Description

What this part is

An NSK double-row spherical roller bearing, 60 mm bore x 110 mm outside diameter x 28 mm wide, in the ISO 222 dimension series, with a tapered bore. Two rows of barrel rollers share 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.
12 — bore code for a 60 mm bore.
CD — NSK’s internal design and cage code: a floating centre guide ring between the two roller rows, with a pressed steel cage. This is the character pair most often misread on NSK spherical rollers, because a leading C looks like a clearance class. It is not a clearance code — NSK’s own table lists C and CD together as a design-and-cage entry, and the clearance on this bearing is stated separately as C3.
K — tapered bore, taper ratio 1:12. The character that decides how the bearing mounts.
E4 — oil groove plus lubrication holes in the outer ring. This is NSK’s code for the feature the rest of the industry writes as W33, which is why both forms are carried on this listing. E4 is a lubrication feature, not a capacity code.
C3 — radial internal clearance greater than Normal.

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 H312 adapter sleeve, letting the bearing clamp anywhere along a plain 55 mm shaft. The shaft is 55 mm and not 60 mm — the sleeve wall takes up the difference, and getting that wrong is the most common ordering mistake on tapered-bore bearings. H-series adapter sleeves are normally supplied complete with their locknut and lockwasher; NSK’s equivalents are the AN12 nut and AW12X washer, and NSK sells the complete adapter as H312X.
An AHX312 withdrawal sleeve, where the bearing sits on a stepped 55 mm seat. Withdrawal sleeves are supplied without a nut, which is ordered separately.

The reason to accept the extra part is control. How far you draw the bearing up the sleeve sets how much the inner ring expands, and therefore the running clearance you end up with — and it lets you mount a bearing anywhere along a length of plain round bar with no machined seat. Measure the clearance reduction as you tighten: over-driving preloads the bearing before it ever turns and is the classic commissioning failure, and under-driving lets the inner ring creep on the sleeve.

C3 clearance starts looser than Normal when cold, so working clearance survives the inner ring growing under a tight fit and operating heat — a sensible pairing with a tapered bore, where the mounting itself already takes clearance out. The outer-ring groove and holes let grease or oil be fed straight into the roller rows through the housing, which is the biggest single factor in how long the bearing lasts, provided the housing has a lubrication port aligned to the groove.

Published ratings and mounting data

NSK publishes the following for the 22212EAKE4 in this envelope:

Basic dynamic load rating Cr: 178 000 N
Basic static load rating C0r: 174 000 N
Thermal speed rating (oil bath, ISO 15312): 5 300 rpm
Mechanical speed rating: 8 000 rpm
Limiting speed: 4 800 rpm on grease, 6 000 rpm in an oil bath
Calculation factors: e = 0.23, Y0 = 2.9
Mass: approximately 1.1 kg
Adapter sleeve: H312 (NSK complete adapter H312X), for a 55 mm shaft
Withdrawal sleeve: AHX312, for a 55 mm seat

NSK quotes three different speed figures for this family and they are not interchangeable: the thermal rating is where heat generation balances heat dissipation under a standard reference condition, the mechanical rating is the structural ceiling for the cage and rollers, and the limiting speeds are the practical ones you design to, depending on whether you grease or oil the bearing. Comparing an NSK thermal rating against another maker’s limiting speed will mislead you every time.

Quantity and configuration

Sold as 1 Pc. One complete bearing: inner ring with both roller rows, cage and centre guide ring, 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 a torque setting, because the taper turns small axial travel into large radial expansion and torque 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

Dimensionally equivalent tapered-bore 22212 bearings include NSK 22212EAKE4C3 (NSK’s own high-capacity design in the same envelope), SKF 22212 EK, FAG 22212-E1-XL-K, NTN 22212EAKW33, NTN-SNR 22212EAKW33, Timken 22212KEJW33, RHP 22212EKJW33 and Link-Belt 22212LBK — specify C3 to match. All mount on the same H312 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. The lubrication codes are one feature under different letters: E4 on NSK, W33 on SKF, Timken, RHP and Link-Belt, S on FAG, D1 on NTN Japan, B33 on legacy SNR. Two traps — SKF W on its own means the groove and holes are absent, and the straight-bore 22212 is a related size, not an interchange: same envelope, but it mounts directly on a 60 mm shaft and this bearing will not.