NKIA Series – Single-Direction Axial Load

The NKIA series is a combined needle roller bearing that supports both radial loads and axial loads, but only in one direction. It combines a radial needle roller bearing with a single-row angular contact ball bearing. These are ideal for applications where axial forces are present in only one direction. They typically require a shaft shoulder or snap ring to handle the axial positioning.

Example: An NKIA5906 is suitable for a 30mm shaft and supports radial loads along with axial loads in one direction only.

NKIB Series – Bi-Directional Axial Load

The NKIB series is also a combined bearing that supports both radial and axial loads, but unlike the NKIA, it supports axial loads in both directions. It uses a double-row angular contact ball bearing along with needle rollers. This makes NKIB bearings suitable for applications where axial forces alternate or reverse, such as in gearboxes or motor assemblies.

Example: An NKIB5906 fits the same 30mm shaft but can handle axial loads from either direction.

Summary of Differences

• NKIA: Supports axial loads in one direction only, uses a single-row angular contact bearing.
• NKIB: Supports axial loads in both directions, uses a double-row angular contact bearing.
• Both types handle radial loads via needle rollers.
• NKIB is preferred in applications where axial load direction may change.