What is the common term for long parallel rollers in bearings?

The common term for long parallel rollers in bearings is needle bearings. Needle bearings are a type of roller bearing that uses cylindrical rollers that are elongated, which resemble needles. This design allows them to carry a heavier load in a compact space compared to standard roller bearings, making them particularly effective in applications where space is a constraint.

Needle bearings are often used in machinery and automotive applications due to their ability to reduce friction and support both radial and axial loads. Their design also aids in reducing the overall weight of the assembly while maintaining high performance.

The other types of bearings mentioned have different designs and applications. For instance, ball bearings use spherical balls, roller bearings employ thicker cylindrical rollers, and axial bearings are specifically designed for handling axial loads rather than radial loads. Each bearing type serves a unique purpose based on its mechanical structure and intended application.