NACHI 21308EW33KC3 Spherical Roller Bearing 40x90x23 mm, Tapered bore 1:12, C3

This range covers 11 NACHI E-Series double row spherical roller bearings with tapered bore (1:12 taper, K), W33 outer ring oil holes and groove, and C3 radial internal clearance, from 40 to 190 mm bore (outer diameters 90 to 320 mm, widths 23 to 108 mm). Select the size from the drop-down: each size has its own bearing number, load ratings and speeds in the Model Details.

Spherical roller bearings have two rows of rollers running on a spherical outer ring raceway. They carry heavy radial loads and moderately high axial loads in both directions, have a high impact-load capacity, and tolerate shaft deflection or mounting error.

These are E-series bearings: the E in the model number is the roller bearing design change symbol, and the load ratings and limiting speeds are the general catalogue E-series figures. They are rated on a different basis to the EXQ bearings, so compare speeds only between bearings from the same table.

21315EW33KC3 and 23134EW33KC3 show dimensions only: the catalogue has no E-series rating row for these sizes, so load ratings, speeds and mass are not shown for them. Contact AIMS if you need the figures.

Where this product is used

• Paper mill and rolling mill equipment, and other large machines where shaft deflection or mounting error can occur
• Gearboxes and industrial transmissions carrying heavy radial and combined loads
• Fans, blowers and pumps
• Conveyors, crushers and mining and mineral processing machinery
• General heavy industrial machinery

Features

• Double row spherical roller bearings: the spherical outer ring raceway lets the bearing tolerate shaft deflection and mounting error, about 2 degrees of misalignment under general service conditions
• E-series design with the load ratings and limiting speeds of the general catalogue E rows
• Heat-stabilised as standard for service up to 200 °C, with minimal dimensional change
• W33 outer ring: oil holes and an oil groove to feed lubricant to the rollers, with hole, groove and hole count tabulated for every size
• C3 radial internal clearance, larger than Normal: 50 to 65 µm on the smallest bore up to 220 to 290 µm on the largest
• Tapered bore for an interference fit on a tapered shaft seat or sleeve, which allows the bearing clearance to be set at mounting
• Load ratings, speeds and mass for every size are taken from the manufacturer’s catalogue; the speed basis is the limiting speed in the general catalogue

Key specifications

Available sizes

Speeds are the limiting speed figures (general catalogue). n/a: no E-series rating row in the catalogue for 21315EW33KC3 and 23134EW33KC3; contact AIMS.

Selecting the right option

Choose the bore first, then the outer diameter and width. The first three digits of the model are the bearing series (21300, 22200, 22300, 23000, 23100, 23200 here), and the last two digits multiplied by 5 give the bore in mm, so 22216 is an 80 mm bore. Within one bore size the series changes the outer diameter and width, and with them the load rating. For example, at a 140 mm bore the 23028EW33KC3 measures 210 x 53 mm with a basic dynamic load rating of 585 kN, while the 22328EW33KC3 measures 300 x 102 mm and 1,540 kN.

Every bearing on this page is an E-series design, so the speeds are the general catalogue limiting speeds. EXQ bearings are rated on a different basis (the EXQ brochure), so compare speeds only between bearings from the same table.

C3 clearance is larger than Normal. It suits a tight shaft fit or a temperature difference between the inner and outer ring, both of which take up clearance; the Model Details give the exact micrometre range for each size.

The bore is tapered, so the shaft seat must be tapered or the bearing mounted on a sleeve; a straight shaft will not take it directly. All sizes have a 1:12 taper.

Fitting and use

Where there is axial load, keep Fa at or below 0.6 Fr, and check with AIMS above that. A bearing running with no load can skid, so apply a load greater than 0.02 Cr.

Tapered bore bearings are always fitted with an interference fit on the shaft, on a tapered shaft seat or an adapter or withdrawal sleeve (ordered separately). Measuring the reduction in radial internal clearance is the more reliable way to set the fit than measuring axial drive-up, and the clearance left after mounting must not fall below the catalogue minimum for the bore size. Ask AIMS about the matching sleeve before ordering.

Misalignment of about 2 degrees is permitted under general service conditions. Misaligned bearings run noisier as speed rises, so the practical limit can be lower. Check fluctuating loads, oscillating loads (such as shaker screens) and high speed with AIMS before ordering.

W33 means the outer ring has oil holes and an oil groove. Line the housing lubricant port up with the groove so lubricant reaches the rollers.

Related products

Other NACHI spherical roller bearings from AIMS: NACHI E-series spherical roller bearings with straight bore (6 sizes, 140 to 240 mm bore), NACHI EXQ spherical roller bearings with tapered bore (62 sizes, 25 to 180 mm bore), NACHI EXQ spherical roller bearings with straight bore (60 sizes, 25 to 160 mm bore) and NACHI spherical roller thrust bearings (5 sizes).