Double Row Cylindrical Roller Bearing

A two-row cylindrical roller bearing is designed for increased strength in carrying radial loads. These bearings are interchangeable and are available in the same size range as the single row product. They feature a standard drilled pocket finger bronze retainer and a cylindrical cage. The inner ring is also interchangeable with those of competitors.

Stiffness matrix formulation for double row angular contact ball bearings

An analytical stiffness matrix formulation for double row angular-contact ball bearings is presented. The formulation takes into account the dynamic effects of the balls and includes a new approach to the computation of the stiffness matrix. The new method gives a more precise result and is similar in computational cost to previous studies.

In order for a double row angular contact ball bearing to be stiff, it must be subjected to a sufficient load. Typically, the minimum radial load required is P > C0r/100. However, it is often higher than this because of the weight of the supported part or other external forces.

Basic rating life equation for cylindrical roller bearings

The basic rating life equation for cylindrical roller bearings is based on the assumption that the load applied to the bearing is constant, either axially or radially. For cylindrical roller bearings, the basic rating life equation assumes a constant radial load P, and a constant speed n. In cases where the bearing will be subjected to non-constant loads, equivalent operating values can be calculated. These operating values induce the same fatigue in the bearing as actual loading conditions.

In some cases, a heavily loaded bearing will suffer from a higher temperature on the sliding contact than the stationary ring. This difference in temperature can be up to 20 K. This difference in temperature cannot be affected by external heat sources. Therefore, the EP additives must be taken into account when calculating the expanded adjusted rating life. Also, the operating life value is given for various mounting locations and speeds. However, it is not recommended to overspecify the bearings because they may not be able to withstand the minimum load.

Applications

Double-row cylindrical roller bearings have a number of advantages, including their axial load carrying capacity. The special curvature of the roller end faces promotes optimum contact conditions, minimizes axial contact pressures on the ribs, and forms a lubricant film that supports higher loads. They also eliminate wear at the running surface of the ribs and roller end faces, which helps to reduce the frictional torque.

Cylindrical roller bearings with double-row angular contact surfaces are primarily used in applications that require a low-friction bearing. In some cases, they're used to support a single row of bearings. These can be self-retaining, or non-self-retaining. They're also easier to mount compared to bearings without ribs or bearing sections.

Support for radial loads

Double row cylindrical roller bearings are designed to support heavy radial loads. Their open flange design and logarithmic roller profile facilitate the formation of a hydrodynamic lubricant film. These double row cylindrical roller bearings are available in a wide range of sizes and offer superior performance compared to standard cylindrical roller bearings. They also feature a modified internal construction, optimised roller-raceway contact geometry, and optimised surface quality and lubricant film formation.

The rotation speed of a bearing is also an important consideration. Some types of bearings are capable of sustaining high speeds, but this can reduce the amount of load they can support. Also, it is important to consider the possibility of misalignment. For example, double-row ball bearings should not be used in misaligned applications.

Sizes available

Cylindrical roller bearings are available in single, double and four row configurations. They feature linear contact between the raceway and the rollers and are suitable for heavy radial and impact loads. Cylindrical roller bearings are available in different sizes and are also available with thrust collars and lubrication holes.

Single row cylindrical roller bearings have a small outer diameter. Double row bearings are available in 120 mm outer diameter. Double row cylindrical roller bearings are stabilized up to 150 degrees Celsius. The operating temperature of these bearings is limited by their dimensional stability and the lubricant used in their manufacture.