NACHI 22205EXQW33KC3 Spherical Roller Bearing 25x52x18 mm, Tapered bore 1:12, C3

This range covers 62 NACHI EXQ double row spherical roller bearings with tapered bore (1:12 taper, K, and 1:30 taper, K30, on 9 sizes), W33 outer ring oil holes and groove, and C3 radial internal clearance, from 25 to 180 mm bore (outer diameters 52 to 280 mm, widths 18 to 100 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.

EXQ is the high-load-capacity EX bearing with the Q axial-load-capacity and high-speed specification. Raceway and roller curvature are optimised for axial load, a floating guide ring controls the roller movement, and a high-strength pressed steel cage encloses the roller set. The rings are made from high-cleanliness steel and heat-stabilised as standard for service up to 200 °C.

The taper differs by series. The 9 sizes in the 240 and 241 series (24024, 24026, 24028, 24030, 24122, 24124, 24126, 24128, 24130) have a 1:30 taper, which the catalogue codes K30, even though the stock model number carries K. All other sizes on this page have the standard 1:12 taper (K).

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
• EXQ design: raceway and roller curvature optimised for axial load, with a floating guide ring and a high-strength pressed steel cage
• Lower temperature rise and higher permissible rotating speeds than the conventional E/EX bearing of the same size (for example the 22206EXQ is rated 9,400 rpm on grease against 8,500 rpm for the conventional 22206 in the general catalogue)
• High-cleanliness steel and optimised internal specifications; heat-stabilised as standard for service up to 200 °C
• 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: 40 to 55 µm on the smallest bore up to 200 to 260 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 permissible rotating speed in the EXQ brochure

Key specifications

Available sizes

Speeds are the permissible rotating speed figures (EXQ brochure).

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, 24000, 24100 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 120 mm bore the 23024EXQW33KC3 measures 180 x 46 mm with a basic dynamic load rating of 430 kN, while the 22324EXQW33KC3 measures 260 x 86 mm and 1,250 kN.

Every bearing on this page is an EXQ design, so the speeds are the EXQ brochure permissible rotating speeds. These are higher than the conventional E/EX figures for the same size, so check which basis a comparison quote uses.

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. Sizes in the 240 and 241 series have a 1:30 taper and every other size has 1:12, so check the taper of the shaft seat or sleeve against the size you select.

Fitting and use

Where there is axial load, keep Fa/Fr at or below 0.8, and check with AIMS above that. A bearing running with no load can skid, so apply a radial load of at least 0.015 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 EXQ spherical roller bearings with straight bore (60 sizes, 25 to 160 mm bore), NACHI E-series spherical roller bearings with tapered bore (11 sizes, 40 to 190 mm bore), NACHI E-series spherical roller bearings with straight bore (6 sizes, 140 to 240 mm bore) and NACHI spherical roller thrust bearings (5 sizes).