TimkenLM451349V-90090Two-Row Tapered Roller Bearing Assembly – Back to Back with Cup Spacer, 10.5000 in Bore, 14.0000 in OD, Class 3, Steel

Product Description

What this part is

Timken LM451349V-90090 matched two-row tapered roller bearing assembly in the LM451300 imperial series. Bore 10.5 in (266.7 mm), cup outside diameter 14 in (355.6 mm). The rows sit back to back with a cup spacer between them, giving a wide effective load spread and a bearing that takes radial load, thrust in both directions and overturning moment in one mounting.

Decoding the designation

The trailing 90090 marks a Timken matched assembly: the cones, cups and spacers are ground and gauged together to a set internal condition and shipped as one part number. The base geometry is the LM451349 cone against the LM451310 cup. The trailing 3 on both component numbers is Timken precision Class 3, a tighter running-accuracy grade than the standard Class 0 or Class 2 tapered roller bearing.

What these specs mean in practice

Single-row dynamic radial rating for this row geometry is 51,300 lbf at 90 million revolutions, with a single-row dynamic thrust rating of 31,600 lbf. The K factor of 1.62 is the ratio of radial to thrust capability and sets the thrust component generated by a given radial load. ISO factors are e 0.76, Y1 0.88 and Y2 1.31. Thirty-nine tapered rollers run in each row against a stamped steel cage. Class 3 tolerances tighten bore, outside diameter and runout over standard grades, which matters where the housing and shaft fits are held closely and where shaft position under load is a design constraint.

Quantity and configuration

One matched assembly. The carton marking lists two LM451349-3 cones, two LM451310-3 cups, one XC2448-S spacer and one LM451310EW. Sale unit is 1 Pc, the assembly.

Mounting dimensions

Cone backface backing diameter 11.22 in (285.00 mm) and cup frontface backing diameter 13.52 in (343.41 mm) define the shoulder faces the bearing seats against. Maximum shaft and housing fillet radii cleared by the bearing corners are 0.14 in (3.600 mm) at the cone backface and 0.06 in (1.5 mm) at the cup frontface. Cage-to-cone face clearances are 0.19 in (4.8 mm) at the backface and 0.18 in (4.6 mm) at the frontface.

Fitting notes

A matched assembly is installed as supplied, with the spacer between the rows in the ground orientation it left the factory in. The internal setting comes from the ground spacer stack rather than from adjustment at assembly, so the mounting only needs the shoulders, fits and clamp-up to be correct.

Interchange guidance

The LM451349 – LM451310CD assembly shares this bore, outside diameter, cone geometry and set of ISO factors but is a TDO build using a one-piece double cup, so it is a related size with a different effective spread and different two-row ratings. Assemblies in the LM451300 series carrying other 90-series suffixes differ in internal setting and component mix.