Needle bushes

A needle bush is a needle bearing with the smallest radial overall height. It consists of non-cutting, thin-walled outer sleeves and needle roller and cage assemblies, which together form a structural unit. These bearings enable particularly space-saving and easy-to-mount bearings with high radial load carrying capacity. They can be combined with axial needle roller bearings AXW to absorb axial forces. Most of the bearings are single-row and have no lubrication hole. Two-row versions have a lubrication hole and the suffix ZW. Needle bushings require that the bearing race on the shaft is hardened and ground. If the shaft cannot be designed as a raceway, then the bearings can be combined with the inner rings IR or LR. If axial filter elements such as shoulders and snap rings are not used, the housing bore can be designed easily and particularly economically. At the same time, this simplifies the installation of the bearings. Needle bushes are closed on one side. They are therefore well suited to terminating bearing points on shaft ends. This provides protection against accidents when the shaft is rotating and the bearings are protected from dirt and moisture. The bottom is smooth or beaded (stiffened) depending on the size. Due to the profiled bottom, small axial guides are also possible. Needle bushes are available in unsealed versions according to DIN 618-1 / ISO 3 245 and sealed according to DIN 618-2. Under normal operating conditions, the lip seals protect against dirt, splash water and the loss of lubricant. Sealed bearings are greased with a lithium complex soap grease according to GA08. Unsealed bearings can be used at temperatures up to +140°C. Sealed needle bushings are suitable for temperatures from -30°C to +100°C, limited by the lubricant and sealing material. Bearings with a plastic cage are suitable for operating temperatures from -20°C to +120°C.