TimkenNA41125Tapered Roller Bearing Single Cone 1-1/8″ Bore, Two-Row Service, Cone Only, 1 Pc

Product Description

What this part is

A Timken inch-series tapered roller bearing cone, part number NA41125. The cone carries the inner raceway, the tapered rollers and the cage as one non-separable unit. Bore is 1.1250 in (28.575 mm). Cone only. The matching cup is the Timken 41286.

Decoding the designation

In the Timken inch scheme the number identifies the cone geometry and the prefix identifies its service variant. The NA prefix marks a cone furnished for two-row and TDO service, which is the same raceway geometry as the plain 41125 cone produced to the tolerance and finish used where two cones share one cup or run against a common spacer. The trailing number carries no dimensional meaning of its own; the 41125 identity fixes the bore, the raceway angle and the roller path, and the mating cup number 41286 is a separate part number.

What these specs mean in practice

A tapered roller bearing converts part of its radial load into an axial reaction along the raceway taper, so a single row locates a shaft in one direction and a pair is mounted in opposition to locate it in both. A cone furnished for two-row service is intended to sit alongside a second cone, either against a double cup or across a cone spacer, and in that arrangement the internal setting is governed by the spacer width rather than by adjustment at assembly.

Quantity and configuration

1 Pc. Cone only, comprising inner ring, rollers and cage. Supplied without the 41286 cup and without any cone or cup spacer.

Fitting notes

The cone is an interference fit on the shaft seat and the mounting force is applied to the cone backface, not through the rollers. In a two-row mounting the cone backfaces bear against the spacer or against each other, so the seat length and the shoulder position govern the finished row spacing.

Interchange guidance

The matching cup is the Timken 41286. The plain Timken 41125 cone shares the raceway geometry and is the single-row form of the same part. A 41286-B is a flanged cup for the same raceway family, so the cup choice changes the housing mounting rather than the bearing geometry. Cones in adjacent 411xx numbers are related sizes with different bores and are not interchangeable.