Introduction of Needle Bearing

Drawn cup needle roller bearings with open ends and with closed end are needle roller bearings with a very small radial section height. They comprise thin-walled, drawn cup outer rings and needle roller and cage assemblies which together form a complete unit.

These bearings allow the design of particularly compact and easy to fit bearing arrangements with high radial load carrying capacity. In order to support axial forces, they can also be combined with axial needle roller bearings AXW, series AXW, see dimension table,

The majority of the bearings are of a single row design and do not have a lubrication hole. Double row designs have a lubrication hole and the suffix ZW.

A needle roller bearing is a bearing which uses small cylindrical rollers.

They are used to reduce friction of a rotating surface.
Needle bearings have a large surface area that is in contact with the bearing outer surfaces compared to ball bearings. Additionally there is less added clearance (difference between the diameter of the shaft and the diameter of the bearing) so they are much more compact.

The typical structure consists of a needle cage which orients and contains the needle rollers, the needle rollers themselves, and an outer race (sometimes the housing itself).
Radial needle bearings are cylindrical and use rollers parallel to the axis of the shaft. Thrust needle bearings are flat and use a radial pattern of needles.
Full complement bearings have solid inner and outer rings and rib-guided cylindrical rollers. Since these bearings have the largest possible number of rolling elements, they have extremely high radial load carrying capacity and are suitable for particularly compact designs.