FAGDouble-Row Spherical Roller Bearing – 90 mm Tapered Bore (1:12), 160 mm OD, 40 mm Width, W33 Lubrication Groove, Open, CN Clearance

Product Description

What this part is

A FAG 22218-AS-K-J-W33 double-row spherical roller bearing, 90 mm bore, 160 mm outside diameter, 40 mm width. The bore is tapered at 1:12. Two rows of barrel-profile rollers run on a common spherical raceway in the outer ring, which is what makes the bearing self-aligning: the inner ring, rollers and cage swivel as an assembly inside the outer ring to absorb shaft misalignment and housing deflection without loading the roller ends.

Decoding the designation

222 is the ISO dimension series and 18 the bore code, giving a 90 mm bore. K is the 1:12 tapered bore. AS is the FAG lubrication feature on the outer ring — a circumferential groove with radial feed holes — and W33 is the ISO code for the same arrangement, one groove plus three holes. J is the pressed steel cage. No clearance suffix appears, so the bearing is normal clearance, CN.

What these specs mean in practice

A double-row spherical roller bearing carries very high radial load and takes thrust in both directions, which is what separates it from a single-row barrel roller bearing of similar appearance. Self-alignment is typically good for a degree or two of static misalignment, so the bearing suits long shafts, plummer block pairs and fabricated housings where perfect coaxiality is not achievable. The W33 groove and holes let grease or oil enter at the centre of the outer raceway and feed both roller rows evenly, which matters on a bearing this size under continuous relubrication.

Tapered bore and adapter sleeve

The 1:12 tapered bore mounts on a matching tapered shaft seat, or on a cylindrical shaft by way of an adapter sleeve. For a 22218 K the matching sleeve is an H318. An H318 fits an 80 mm cylindrical shaft, so the shaft diameter is one bore-code step below the 90 mm bearing bore, and the sleeve is used with a KM18 locknut and an MB18 lockwasher. Driving the inner ring up the taper reduces the radial internal clearance by a controlled amount, so the mounted clearance is set by drive-up distance rather than by the unmounted CN figure.

Mounting data

Bearing bore: 90 mm, tapered 1:12. Adapter sleeve shaft seat: 80 mm. Internal clearance as supplied: CN, normal. Item weight: 7.5 lbs. Operating temperature range: -30 °C to 200 °C.

Quantity and configuration

Unit Quantity: 1 Pc. Bearing only, open on both faces. The matching adapter sleeve is the H318, used with a KM18 locknut and an MB18 lockwasher.

Interchange guidance

SKF 22218 EK and NSK 22218EAKE4 are the same 90x160x40 mm tapered-bore W33 envelope and are direct functional equivalents, the NSK E4 code carrying the same groove-and-holes feature as W33. Timken 22218KEJW33 is the same specification. A 22218 without the K has a straight bore and needs no sleeve, and a 22218 in the 22200 series without W33 has a plain outer ring, so both are related sizes rather than interchanges. FAG’s E1A execution of the same envelope carries a machined brass cage and a higher rating.