High Quality Cylindrical Roller Bearings: types and dimensions

What are cylindrical roller bearings?

Cylindrical roller bearings have a single , double or more  rows of  rolling elements  using cylindrical rollers. Compared to the ball, the roller has a larger contact area perpendicular to the roller axis. This means cylindrical rollers can transmit higher forces, have greater rigidity and utilize smaller rolling element diameters under the same load.

Based on the design of the ribs on the bearing rings axial forces can be supported in one or both directions, axial displacements of the shaft relative to the housing are compensated without constraints.

Cylindrical roller bearings are manufactured to be separated for easier mounting.

As for all rolling bearings Cylindrical roller bearings are used to manage friction between moving parts of machines, particularly where high radial loads are involved.
Cylindrical roller bearings feature cylindrical rollers as their rolling elements,  arranged between inner and outer rings. Different from ball bearings, is their design, which provides a larger contact area with the raceways. This design characteristic allows them to accommodate higher radial loads, making them highly suitable for applications involving heavy machinery and equipment.

The rollers in these bearings are designed to facilitate smooth motion and ensure stability by distributing the load evenly across a wide surface area, thereby reducing stress and wear on the machine parts. Their efficiency and durability make cylindrical roller bearings a critical component in enhancing the performance and reliability of various mechanical systems.

Cylindrical roller bearings types

There are various types of Cylindrical Roller Bearings,  they all have rollers guided on one raceway ring between retaining shoulders and captured by the cage.

The outer ring can be detached. In some cases full complement (no cage) are used to increase load carrying capacity. The arrangement types have different arrangements for the shoulders or lips.

What is N type cylindrical roller bearing?

The N type cylindrical roller bearing is a distinctive variation, characterized by its inner ring design that allows for both axial displacement and high radial load capacity. Unlike other types, the N type features an inner ring with two integral flanges while the outer ring is flangeless. This configuration facilitates axial displacement of the shaft in relation to the housing in one direction, making it particularly valuable in applications where thermal expansion of the shaft or misalignment could be issues.

The design of the N type bearing enables it to accommodate high radial loads because the rollers are in linear contact with the raceways, providing a high load-bearing capacity. Additionally, the absence of an outer flange reduces friction and enables easier assembly and disassembly, which is particularly advantageous during maintenance and installation processes.

This type of bearing is often used in applications such as electric motors, gearboxes, and in machinery where axial displacement is expected due to thermal expansion and where precise shaft alignment is difficult to maintain. The N type cylindrical roller bearing’s ability to handle high radial loads while allowing for axial displacement makes it an excellent choice for a wide range of industrial applications, offering both flexibility and robust performance.

Type NU has two shoulder lips on the outer ring, the inner ring then would have no lips, In Type N the inner ring has two shoulder lips and the outer ring has none. Cylindrical roller bearings of types NU and N are used as floating bearings. Type NJ has two shoulder lips on the outer ring and one on the inner ring it can take up axial forces in one direction.

Many manufacturers such as INA and SKF design these bearings with an extra capacity (E) type having the same external design but employing rollers having larger diameters and lengths. The Extra capacity type increases the load carrying capacity.

The basic raceway shape of a cylindrical roller bearing is cylindrical as well. A limited degree of misalignment tolerance can be achieved by a slightly spherical shape of one of the raceways.

Such bearings are less susceptible to shaft deflection and misalignment. The rollers of cylindrical roller bearings are ground with a spherical transition zone between the cylindrical periphery and the rounded corner or radius. The cylindrical-spherical profile prevents the occurrence of edge stresses and achieves a modified line contact with uniform stress distribution.

Double row cylindrical roller bearings are produced for machine tool spindles  due to their increased accuracy.

Double Row cylindrical roller bearings produced with a taper will have a K designation.

Four Row cylindrical Roller bearings are ideal for use in Rolling Mills where heavy loads are present. Multirow cylindrical roller bearings are frequently specified for Back-Up and and work rolls in rolling mills. The rollers of these bearings are through bored and are guided by the pins of the cage. The pin type cage used in these bearings accommodates the highest number of rollers and therefore provides the high load ratings.

Lighter and Medium duty cylindrical roller bearings usually are manufactured with steel cages. The larger or heavier duty cylindrical roller bearings are generally manufactured using machined cages made from steel,alloys or brass and are likely guided on the rollers. In high speed applications then the cage is guided on the ground lips or shoulders of the inner or outer ring.

Because the cylindrical roller bearing is manufactured in such a way the bearing can be easily separated making it possible to mount both rings with tight fit.

Аpplications for cylindrical roller bearings

There are many applications for cylindrical roller bearings. The main applications however for cylindrical roller bearings are in power transmission applications.  A few applications they are used in are vibratory machines and rail vehicle wheel sets. As floating bearings they are commonly used in electric motors. The bearing kinematics and low friction of cylindrical roller bearings make them very suitable for high speed applications.

Cylindrical roller bearings with optimized rib contact.

Key applications where cylindrical roller bearings are commonly used:

• Electric Motors and Generators: Their ability to handle high radial loads and operate at high speeds with minimal noise and vibration makes cylindrical roller bearings ideal for electric motors and generators.

• Automotive Industry: Within the automotive sector, these bearings are utilized in transmissions, differentials, and other components where support for high radial loads is necessary. They help in achieving smoother operation and enhanced durability of the vehicle components.

• Industrial Gearboxes: Gearboxes benefit from the high load-bearing capacity and durability of cylindrical roller bearings, ensuring efficient power transmission and operational reliability in industrial machinery.

• Wind Turbines: The wind energy sector relies on these bearings for the main shafts of wind turbines. Their capacity to manage high radial loads and withstand challenging environmental conditions makes them a preferred choice.

• Railway Axleboxes: The railway industry uses cylindrical roller bearings in axleboxes of locomotives and rolling stock. Their robustness and ability to accommodate axle movements and shocks are critical for the safety and reliability of railway operations.

• Material Handling Equipment: In conveyors, hoists, and lifting equipment, these bearings facilitate smooth motion and high load capacity, crucial for efficient material handling and minimal downtime.

• Pumps and Compressors: The precision and efficiency of cylindrical roller bearings support the operation of pumps and compressors in various industries, including oil and gas, water treatment, and manufacturing, contributing to their performance and reliability.

Conclusion

High-quality cylindrical roller bearings are essential components in a wide range of industrial applications, offering unparalleled support in managing radial loads and facilitating smooth operations. From the standard design to the specialized N type, each variant caters to specific requirements, providing engineers and professionals with the flexibility to choose the optimal bearing for their application based on load capacities, dimensions, and operational conditions.

Understanding the different types and dimensions of cylindrical roller bearings is crucial in making informed decisions that enhance efficiency, reduce maintenance costs, and extend the lifespan of machinery.

Our store offers a comprehensive range of high-quality bearings designed to meet the specific needs of various industrial applications. With expert advice and a wide array of options, PIB Sales is your go-to destination for all your bearing needs.

Visit the PIB Sales shop today to discover the perfect solution for your machinery.

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