NA49 RNA49 Heavy duty needle roller bearing, 49 series

Heavy duty needle roller bearings have a machined and ground channel-shaped outer ring with a complement of needle rollers retained and guided by a cage. The thick outer ring provides maximum load capacity and shock resistance with a relatively small radial cross section. With the high-strength cage retaining and guiding the rollers, this design provides high speed and lubrication retention capability. The assembled G2 grade needle roller has a diameter variation of less than 2μm in groups. In addition to fully loaded needle bearing, all adopt high rigidity cage, which can correctly guide the needle parallel to the axis.