Page 8 - needle bearings

Classification and Characteristics of Bearings
NTN

1. Classification and Characteristics Bearings

Needle roller bearings have relatively smaller diameter their volume. Also, because the inertial force action on
cylindrical rolling elements whose length is much larger them is limited, they are ideal choice for oscillating
than their diameter. motion. Needle roller bearings contribute to compact and
Compared with other types of rolling bearings, needle lightweight machine designs. They serve also as a ready
roller bearings have a small cross-sectional height and replacement for sliding bearings.
significant load-bearing capacity and rigidity relative to NTN offers the following types of needle roller bearings.

Needle roller and cage assembly
This assembly, a major component of a
needle roller bearing, comprises needle rollers
and a cage to support the rollers.
¡Using the shaft and housing as raceway
surfaces reduces the cross-sectional
height: it is equal to the diameter of the
needle roller bearing.
¡This structure eliminating the outer and
inner rings allows the bearing to be fitted
more easily.
¡The assembly is available in both single-row
and double-row configurations.
¡As long as the tolerance limit of the shaft
and housing is satisfied, the radial internal
clearance can be made adjustable.

Needle roller and cage assembly for connecting rods

This assembly, a major component of a needle roller bearing, comprising needle rollers and a cage to support the
rollers, is used typically for connecting rods in reciprocating compressors and small- and mid-sized internal combustion
engines such as those for motorbikes, light cars, outboard motors and versatile engines. This assembly features such a
cage that is specifically optimized for severe operating conditions involving high impact loads, complicated motions, high-
speed revolution and/or high operating temperatures.

Needle roller and cage assembly for large end

¡This assembly, subjected to a cranking motion with a
simultaneous action of the rolling elements’ rotation
and revolution, must be light but have a high rigidity,
and must have a precise dimension of the outer
diameter of the cage so that the guiding system can
keep an appropriate gap.
¡The cage is made of high-tensile special steel with a
surface hardening treatment.
¡The guiding system employed is an outer diameter
guiding system.
¡The cage that may be subjected to poor lubrication
can be protected with a surface treatment using a
non-ferrous metal.
¡For applications with a one-piece structure of crank
shaft, the cage of split type is also available.

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