Cylindrical roller bearing size summary

Cylindrical roller bearings are designed to handle heavy radial loads and operate at high speeds. They come in various sizes and configurations to suit different applications. Here’s a summary of the typical sizes and dimensions for cylindrical roller bearings:

Basic Designations

Spindle Bearings

Cylindrical roller bearings are typically categorized by their design, denoted by specific series designations. Common series include:

N Series: Single row, inner ring has two flanges, outer ring has no flanges.

NU Series: Single row, outer ring has two flanges, inner ring has no flanges.

NJ Series: Single row, outer ring has two flanges, inner ring has one flange.

NUP Series: Single row, outer ring has two flanges, inner ring has one flange and a loose flange ring.

NF Series: Single row, outer ring has one flange, inner ring has two flanges.

NN Series: Double row, used for applications requiring high radial load capacity.

NNU Series: Double row, used for high radial load applications with greater rigidity.

Common Sizes and Dimensions

Cylindrical roller bearings come in a wide range of sizes. Here is a summary of typical dimensions for some of the common series:

NU Series

Inner Diameter (d): 20 mm to 400 mm

Outer Diameter (D): 47 mm to 720 mm

Width (B): 14 mm to 180 mm

NJ Series

Inner Diameter (d): 20 mm to 400 mm

Outer Diameter (D): 47 mm to 720 mm

Width (B): 16 mm to 180 mm

NUP Series

Inner Diameter (d): 20 mm to 300 mm

Outer Diameter (D): 47 mm to 460 mm

Width (B): 14 mm to 100 mm

NN Series (Double Row)

Inner Diameter (d): 30 mm to 400 mm

Outer Diameter (D): 55 mm to 600 mm

Width (B): 19 mm to 280 mm

NNU Series (Double Row)

Inner Diameter (d): 30 mm to 400 mm

Outer Diameter (D): 55 mm to 600 mm

Width (B): 19 mm to 280 mm

Specific Examples of Bearing Sizes

Here are some specific examples to illustrate the range of sizes:

NU2205

d: 25 mm

D: 52 mm

B: 18 mm

NJ306

d: 30 mm

D: 72 mm

B: 19 mm

NUP310

d: 50 mm

D: 110 mm

B: 27 mm

NN3010

d: 50 mm

D: 80 mm

B: 23 mm

NNU4922

d: 110 mm

D: 150 mm

B: 40 mm

Tolerances and Precision Classes

Cylindrical roller bearings are available in various tolerance classes, which determine their precision. Common tolerance classes include:

P0 (Normal): Standard tolerance, suitable for general applications.

P6 (Higher precision): Used in applications requiring higher accuracy and speed.

P5, P4, P2 (High to ultra-high precision): Used in high-precision machinery, such as machine tools and aerospace applications.

Load Ratings

Cylindrical roller bearings are designed to handle high radial loads. The load rating varies based on the bearing size and series:

Dynamic Load Rating (C): The load a bearing can handle for 1 million rotations.

Static Load Rating (C0): The maximum load a bearing can withstand without permanent deformation.

Common Applications

Industrial Gearboxes

Electric Motors

Machine Tools

Rolling Mills

Cranes and Lifting Equipment

Railway Axles

Conclusion

Cylindrical roller bearings come in a wide range of sizes and configurations to accommodate different loads, speeds, and precision requirements. When selecting a bearing, it’s essential to consider the specific requirements of your application, including load capacity, speed, and installation dimensions. Consult the manufacturer’s catalog or technical support for detailed specifications and recommendations tailored to your needs.