Product Details:

Solid ring needle roller bearings with shields consist of one or two rings and a set of needle rollers with a cage. These bearings offer a compact design with high load capacity. Hence, they meet the requirements for lightweight, space-saving, and high power transmission. Depending on the application, bearings with or without an inner ring can be chosen.
Primary Structural Styles
Outer race double-lip (or double-lug) retaining ring needle roller bearing, NA, NKI type
The inner and outer rings (with locking rings, complete set of roller pins, and retainers) can be installed separately. It offers high permissible rotational speeds and comes in both single-row and double-row configurations.
If the shaft cannot be used as a raceway, i.e., when hardening the shaft and using grinding is impractical or uneconomical, you can opt for this type of needle roller bearing with an inner ring.
Bearings with cage and no inner ring
NA, NKI type bearings without the inner ring are equivalent to RNA, NK type needle roller bearings.
This bearing is without an inner race, suitable for support structures with limited radial installation dimensions. The shaft collar mating with the bearing serves as the rolling surface. The shaft acting as the raceway must be hardened and ground, and only when processed to the appropriate size and shape accuracy can the full set of roller bearings achieve a longer service life and higher running precision. Additionally, due to the absence of an inner race, the shaft diameter can also be increased appropriately, thereby enhancing rigidity.
Sealed needle roller bearings with or without inner rings
Single or double sealed needle roller bearings effectively prevent the intrusion of dirt, with an appropriate amount of lithium-based grease pre-filled inside. These bearings have an inner race wider than the outer race, ensuring good sealing even when there is a slight relative displacement of the shaft within the bearing housing, thus preventing shaft contamination. The inner race also features oil holes, which can be supplemented with lubrication from either the outer or inner race as needed.