Timken15580B/15520Tapered Roller Bearing Cone and Cup Assembly, 1-1/16 in ID x 2-1/4 in OD x 0.6875 in Wide, Single-Row Imperial TS

Product Description

What this part is

This is a complete single-row imperial tapered roller bearing in the Timken TS (Tapered Single) style. It is the most common tapered roller configuration in industry: a cone, the inner ring with its roller and cage assembly, that runs inside a separate cup, the outer ring. Cone and cup are separable parts, sold and stocked independently.

Cone and cup inclusion

The bearing pictured is assembled, with the cone and its rollers seated inside its outer cup, in its original poly bag, alongside the Timken carton marked 15580B / 15520. This listing is a complete bearing assembly: one cone (15580B) plus one cup (15520).

Designation breakdown

15580: the Timken cone, inner ring plus tapered rollers and cage, 1.0625 in bore. 15520: the matching Timken cup, outer ring, 2.25 in O.D. 15580B: the carton on this item reads 15580B rather than plain 15580, the trailing B being a Timken cone-specific marking, recorded here and in the cross-references exactly as printed on the box and treated as the 15580 cone envelope. Written as a pair, 15580/15520 is the assembly number. Cone-and-cup pairs in the 155xx family share the 15520 cup, so 15578/15520, 15580/15520 and 15590/15520 differ only in bore.

Specifications in application

A tapered roller bearing carries heavy radial load and thrust in one direction only, because the rollers and races are set on a cone angle that pushes the cone out of the cup under reverse thrust. Tapered rollers are therefore almost always mounted in opposing pairs, two bearings back-to-back or face-to-face on the same shaft, so that each one takes thrust one way and the pair is stable.

The K factor of 1.69 is the ratio of radial to thrust rating for this geometry. The Y factor of 1.73 and e factor of 0.35 are the equivalent-load calculation inputs for combined rather than purely radial load. Cone and cup are separable, so the cone seats on the shaft and the cup in the housing independently, with endplay or preload set by adjusting the two against each other.

Published ratings

All figures below are from The Timken Company’s own catalogue entry for 15580 / 15520. Bore (d): 1.0625 in / 26.988 mm. Outside diameter (D): 2.25 in / 57.150 mm. Assembled width (T): 0.6875 in / 17.463 mm. Cone (inner ring) width B: 0.6875 in / 17.463 mm. Cup (outer ring) width C: 0.5313 in / 13.495 mm. Dynamic radial load rating C1 (ISO, 1 million revs): 10,300 lbf / 46,000 N. Dynamic radial load rating C90 (Timken method, 90 million revs): 2,680 lbf / 11,900 N. Dynamic axial rating Ca90: 1,590 lbf / 7,070 N. Static radial load rating C0: 11,300 lbf / 50,100 N. K factor: 1.69. e factor: 0.35. Y factor: 1.73. G1 factor: 12.7. G2 factor: 10.3. Geometry factor Cg: 0.0577. Catalogue weight: 0.4 lb / 0.20 kg.

Mounting data

Effective centre location: −0.2 in / −5.1 mm, inside the cone backface. Shaft backing shoulder diameter: 1.26 in / 32 mm frontface (da), 1.52 in / 38.5 mm backface (db). Housing backing shoulder diameter: 2.11 in / 53.10 mm frontface (Da), 2.01 in / 51.05 mm backface (Db). Maximum shaft fillet radius: 0.14 in / 3.600 mm. Maximum housing fillet radius: 0.06 in / 1.52 mm. Cage location relative to backface (Aa): 0 in. Cage location relative to frontface (Ab): 0.1 in / 2.5 mm.

Quantity and configuration

One bearing assembly: one 15580B cone plus one 15520 cup. An opposed-pair application takes two assemblies.

Condition

New old stock in the original Timken carton, with the bearing still in its factory wrapping and its preservative coating.

Interchange guidance

15580 and 15520 are industry-standard ANSI/ABMA imperial tapered roller part numbers, so the same numbers are used by SKF, NTN, Koyo, NSK, Fersa, Nachi and others for the same boundary dimensions. Load ratings and internal geometry differ between makers even when the number matches. Timken is also the successor brand to Fafnir and to Torrington bearing lines, so Fafnir-era references may point here.