Needle roller bearings are a type of rolling bearing that uses slender needles as rolling elements. They are lightweight, high-load-capacity precision transmission components. Their core feature is that the length-to-diameter ratio of the needles far exceeds that of ordinary balls, enabling them to withstand extremely high radial loads within minimal installation space.

Needle roller bearings are primarily categorized into two types: those with an inner ring and those without an inner ring. Common series include HK (stamped outer ring), NA (solid outer ring with inner ring), RNA (solid outer ring without inner ring), and TLA (stamped outer ring without inner ring). Manufactured from high-carbon chromium bearing steel or stainless steel, these components achieve a hardness of HRC 62-65 after quenching heat treatment, delivering exceptional wear resistance, impact resistance, and high-temperature tolerance.

Their advantages lie in compact size, light weight, high load capacity, and low friction coefficient, making them ideal for high-speed reciprocating or rotational motion applications. They effectively compensate for installation coaxiality errors. Widely used in automotive transmissions, motors, construction machinery, automation equipment, medical devices, and agricultural machinery, they serve as core transmission components for miniaturized, high-load equipment.