INANA4909-XLMachined Needle Roller Bearing with Inner Ring — 45 mm ID, 68 mm OD, 22 mm Width, Open, Single Row, X-life

Product Description

What this part is:

INA NA4909-XL, a single-row machined needle roller bearing supplied with its own inner ring. Bore: 45 mm. Outside Diameter: 68 mm. Width: 22 mm. Rolling Elements: needle rollers. Closure Type: open. Number Of Rows: 1. Dynamic Load Rating: 51 kN. Static Load Rating: 73 kN. Limiting Speed: 8,600 rpm. Standard: DIN 617 / ISO 1206. Design: X-life.

Decoding the designation:

NA — machined needle roller bearing supplied complete with an inner ring, so it seats on a plain unhardened shaft. The same bearing without the inner ring is an RNA4909.

49 — dimension series 49, the standard-section needle series, which sets the 68 mm outside diameter against the 45 mm bore.

09 — the bore code, 09 x 5 = 45 mm.

XL — X-life execution, INA’s upgraded internal geometry and surface finish rating.

What these specs mean in practice:

Dynamic Load Rating: 51 kN. Static Load Rating: 73 kN. On a needle roller bearing the static figure sitting above the dynamic figure is the normal published relationship, because the line contact of a full needle complement spreads a stationary load over far more raceway area than point contact would. The whole 51 kN comes out of an 11.5 mm radial wall, which is the reason a needle bearing is specified: it delivers roller-bearing capacity in roughly the radial space a ball bearing needs for a fraction of it. Limiting Speed: 8,600 rpm. The inner ring is separable, so the shaft journal does not have to be hardened and ground, and shaft and housing can be worked independently.

Mounting data:

Bore: 45 mm on the supplied inner ring. Outside Diameter: 68 mm. Width: 22 mm across both rings. Radial section: 11.5 mm. The outer ring locates in a plain housing bore; the inner ring is a press fit on the shaft and is fitted separately from the outer ring and needle assembly. Boundary dimensions follow DIN 617 and ISO 1206.

Quantity and configuration:

Unit Quantity: 1 Pc. One bearing comprises the machined outer ring, the caged needle complement and the separable inner ring.

Interchange guidance:

Manufacturer part number variants: NA4909-XL, NA4909XL, NA-4909-XL, NA 49/09 XL, NA4909. Because the envelope is fixed by DIN 617 and ISO 1206, IKO, SKF, NTN, Koyo and Nachi NA4909 parts share the 45 x 68 x 22 mm boundary dimensions. An NA4909-RSR-XL is the sealed execution on the same envelope, and an RNA4909 is the same outer ring and needle assembly running directly on a hardened shaft.