Timken581 / 572Tapered Roller Bearing Cones & Cup – 3.1875 in Bore, 5.5115 in Outside Diameter, 1.4375 in Width, Case-Carburized Steel

Product Description

What this part is

Timken 581 tapered roller bearing cones and a Timken 572 cup, inch TS series. Bore Diameter: 3.1875 in (80.963 mm). Outside Diameter: 5.5115 in (139.992 mm). Overall Width: 1.4375 in (36.513 mm) assembled. Rolling Elements: Tapered Roller. Number Of Rows: 1. Bore Type: Straight. Bearing Material: Case-carburized steel. Item Weight: 2.20 kg (4.80 lb) per complete bearing. Design units are imperial.

Decoding the designation

581 — the cone, the inner ring with its tapered roller set and cage. Inner Ring Width (B): 1.4212 in (36.098 mm).

572 — the cup, the outer ring carrying the mating raceway. Outer Ring Width (C): 1.125 in (28.575 mm).

No precision suffix — Precision Class: Not specified. A Timken precision class is carried by an explicit suffix such as -2 or -3.

What these specs mean in practice

Dynamic Load Rating: 207,000 N (46,500 lbf) at one million revolutions. Static Load Rating: 291,000 N (65,400 lbf). Timken’s 90-million-revolution figures are C90 53,600 N (12,100 lbf) radial and Ca90 37,100 N (8,330 lbf) thrust.

K Factor: 1.45. e Factor: 0.40. Y Factor: 1.49. A K factor of 1.45 is a shallow-to-medium taper angle, which trades some radial capacity for a higher share of thrust capability than a steeper 1.9-class bearing of the same envelope.

G1 Factor: 125.7. G2 Factor: 32. Geometry Factor (Cg): 0.13.

Mounting data

Effective Center Location: -0.21 in (-5.3 mm), inside the cone backface. Max Shaft Fillet Radius: 0.140 in (3.600 mm). Max Housing Fillet Radius: 0.130 in (3.30 mm). Shaft Backing Shoulder Diameter, frontface (da): 3.54 in (90 mm). Shaft Backing Shoulder Diameter, backface (db): 3.78 in (96 mm). Housing Backing Shoulder Diameter, frontface (Da): 5.25 in (133.35 mm). Housing Backing Shoulder Diameter, backface (Db): 4.92 in (124.97 mm). Cage Location relative to backface (Aa): 0.12 in (3 mm). Cage Location relative to frontface (Ab): 0.1 in (2.5 mm).

Quantity and configuration

Unit Quantity: 3 Pcs — two 581 cones and one 572 cup. That builds one complete 581/572 bearing plus a spare cone for a second position running against a cup already in service.

Interchange guidance

581 and 572 are industry-standard inch part numbers shared across the general taper makers, so a 581 cone or 572 cup from SKF, FAG, NSK, NTN, Koyo, Fersa, BCA or PEER interchanges on boundary dimensions and rating class. The 572 has a flanged counterpart, the 572-B, which is a different outer ring.