
IKO NEEDLE ROLLER BEARINGS COMBINED WITH ANGULAR THRUST
BEARINGS are available in the various types shown in the following table.
| Angular contact | Three-point contact |
|---|---|
| NATA 59 | NATB 59 |
These bearings are a combination of a caged needle roller bearing and an angular ball bearing, and the boundary dimension are the international dimension series 59, which conform to ISO standards. They can take a large radial load and a one-directional thrust load at the same time.Needle roller bearing combined with three-point contactWhen the thruse bearing load is more than 25% of the radial load, the radial load acts on the angular ball bearings and affects the bearing life, so careful attentionmust be paid to this load relationship.
If two of these bearing are mounted back to back, a two-directional thrustload can be taken. When mounting, a clearance of 0.2 to 0.3mm in the axial direction is necessary so that radial load is not broughtto bear on the angular ball bearing.
These bearings can take a large load and a two directional thrust load at theAccuracy
same time under high rotational speeds
The inner ring is of the non-interchangeable typt, split in the center of the ball
bearing raceway surface. When mouting the inner ring to shaft, it must be firmly
tightened in the axial direction. The bearing axial clearance is 0.1 to 0.3mm and
the load relationship is the same as that of NATA 59 series; that is, the thrust load
must not be more than 25% of the radial load.
The accuracy of all IKO NEEDLE ROLLER BEARINGS COMBINED WITH ANGULAR THRUST BEARINGS, with the exception of the dimensional tolerance shown below, is manufactured to JIS standardsFit
(1) Tolerance for inner ring width B1 of NATB 59 series: -0.3 mm
(2) In NATB 59 series, the inner ring of narow width side is finished to the bore
dimeter which will allow it to be transition-fitted to a shaft of k5 tolerance.
Shaft with k5 tolerance and housing bore with M6 should be used to these bearingRating life
More tight fit must be avoided to prevent radail load exerted on the balls, due to
perform to their full capacity
As these bearing take radial load on their needle bearing and thrust load on the
angular thrust bearings, the life for each must be calculated separately.