Drawn cup needle roller bearings

A needle sleeve 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 bushes require that the bearing raceway 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 sleeves are open on both sides and come with needle cages or fully needled. Bearings with needle roller and cage assemblies allow higher speeds compared to full needle designs. Due to the maximum number of needle rollers, needle roller bearings with full needles have the highest load capacity in the smallest of spaces. However, their use at high speeds is limited. Since the needles are not held mechanically, the needle rollers are secured with a special grease for transport and assembly (DIN 51825-K1/2K-30). However, this has only an insufficient long-term lubricating effect. Therefore, relubrication is recommended after installation. 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 roller bearings 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.