TimkenLM229139-3Tapered Roller Bearing Cone, 5.625 in / 142.875 mm Bore, 33.00 mm Cone Width, Class 3 Precision, Case-Carburized Steel

Product Description

What this part is

A Timken LM229139-3 single tapered roller bearing cone in Class 3 precision — the inner ring with its full tapered roller set and cage, as one non-separable unit. Brand: Timken. Part Number: LM229139-3. Cone Part Number: LM229139. Base Number: LM229139. Series: Timken imperial LM series, LM2291xx family. Bore: 5.625 in / 142.875 mm. Cone Width: 1.2992 in / 33.000 mm. Number Of Rows: 1. Precision Class: Timken Class 3. Bearing Class: Class 3. Bearing Material: Case-carburized steel. Cage Type: Stamped, roller-guided. Cage Material: Steel. Closure Type: Open. Cone Backface To-Clear Radius: 0.06 in. Cone Frontface Backing Diameter: 5.63 in. Design Units: Imperial (inch). Harmonization Code: 8482.20.00.

Decoding the designation

LM: Timken imperial series prefix, the LM range of tapered roller bearings. 229139: the cone number within the LM2291xx family, which mates the LM229110 cup. -3: Timken precision Class 3, a tighter bore, width and runout grade than the standard Class 4 / K tolerance. Cartons often stamp the class as a leading asterisk, so the same cone reads as LM229139 *3, LM229139-3 and LM2291393.

What these specs mean in practice

At this size the bearing is doing structural work — final drives, planetary carriers, large gearbox output shafts, mill and crusher shafts, heavy axle positions. The taper geometry takes a large radial load and a substantial one-way thrust at the same time, which is why tapered rollers run in opposed pairs: the pair locates the shaft both ways and the axial setting is tuned at build. Class 3 tightens bore, width and runout, so the dialled-in endplay is the endplay delivered, and the gear tooth contact pattern stays where the designer put it.

Quantity and configuration

Cone only — inner ring, rollers and cage as one non-separable unit. Unit Quantity: 1 Pc. Mating cup: Timken LM229110, outside diameter 7.6762 in / 194.975 mm, cup width 1.0827 in / 27.501 mm. The mounted LM229139/LM229110 assembly measures 5.625 in bore x 7.6762 in outside diameter x 1.2993 in overall width (T).

Interchange guidance

The standard assembly is LM229139/LM229110. Inch tapered roller numbering is an industry standard rather than a brand code, so Koyo LM229139, NTN LM229139, SKF LM229139 and the shortened trade form 229139 describe the same cone envelope. A plain LM229139 without the -3 suffix is the same cone in standard Class 4 / K precision and substitutes where the tighter class is not called out; the Class 3 cone fits any standard application. Adjacent cones in the same family, LM229140C, LM229146 and LM229147C, share the LM229110 cup on the same 5.625 in bore and 7.6762 in outside diameter but differ in cone geometry and rating, so they are related sizes rather than direct equivalents.