Advantages

• Due to the smaller cross-section, greater rigidity, higher load-carrying capacity & lower inertia of the needle roller bearings help size and weight reductions in machinery.
• Though they are less wide, their load carrying capacity is high and is most suitable for applications where the load is high & the radial space is less.
• Needle roller bearings, which are designed to withstand oscillation can operate under severe conditions & interchange with sliding bearings.

• Transmissions, transfer cases, engines & valve trains.
• Steering and braking systems.
• Axle support.
• Outboard engines.

• Assemblies with bearings.
• Engineered polymer cages.
• Bearings with one or two seals.
• Closed end bearings.
• Oil holes.
• Drawn sleeves.

• Drawn cup needle roller bearings
• Drawn cup needle roller bearings with closed ends.
• With and without inner rings.

Drawn cup needle roller bearings, are needle roller bearings with a deep thin-walled outer ring with open or closed ends. They have very low sectional height & high load carrying capacity. They are used when the housing bore cannot be used as a raceway & very compact bearing arrangement is required. Drawn cup needle roller bearings are generally used directly on the shaft. Where the shaft cannot be hardened and ground, they can be combined with an inner ring.

Drawn cup needle roller bearings with closed ends. The drawn cup of hardened sheet steel & needle roller & cage assembly forms a non-separable unit. The outside surface of the rollers is slightly relieved towards the roller ends giving a favorable load distribution in the bearing. The space available for lubricant is large. Usually they have a single row of rollers. Some may have two-needle roller and cage assemblies adjacent to each other with the lubrication hole in the outer ring.

With and without inner rings. For applications where a seal is not available, or cannot be used, bearings with integral seals may be used. These are rubbing seals of polyurethane or nitride rubber(NBR). High quality lithium base grease is used in them. To utilize maximum load carrying capacity, the raceways on the shaft must have the hardness and surface finish normally found on bearing raceways. Recommendations will be found in the section.

Needle Roller Bearings Specifications & Standards

Dimensions: The boundary dimensions of the drawn cup needle roller bearings are in accordance with ISO.

Bore Size: Bore is a hollow, usually cylindrical chamber or barrel where the metal balls are to be placed. Its size is measured in millimeters.

Outer Ring Width: It is the width of the outer ring measured in millimeters.

Revolutions: Revolutions indicate the rotation speed of the bearing. Bearing Weight – It indicates the weight of the bearing, measured in pound.

Tolerance: They are usually meant for normal tolerance but can be enhanced.

Internal Clearance: SKF needle roller bearings with inner ring are supplied with Normal radial internal clearance as standard. For needle roller bearings without inner ring, a suitable internal clearance is achieved by selecting appropriate tolerance.

Misalignment: The line contact between the raceways and the rollers prevent damaging edge stresses from occurring & also allows bearings to accommodate very minor angular misalignments of the shaft relative to the housing.

Cages: There are standard cages but some may