Timken3581/3530Tapered Roller Bearing Cone & Cup Set – 1.3750 in Bore, 3.3125 in Outside Diameter, 1.1875 in Width, Case-Carburized Steel

Product Description

What this part is:

Timken 3581/3530 single-row inch tapered roller bearing, supplied as a matched cone and cup. Bore Diameter: 1.3750 in (34.925 mm). Outside Diameter: 3.3125 in (84.138 mm). Overall Width: 1.1875 in (30.163 mm). Series: 3500. Rolling Elements: Tapered Roller. Number Of Rows: 1. Bore Type: Straight. Bearing Material: Case-carburized steel. Item Weight: 0.80 kg (1.80 lb). Design units are imperial.

Decoding the designation:

3581 — the cone, meaning the inner ring together with its tapered roller set and cage. Inner Ring Width (B): 1.2160 in (30.886 mm).

3530 — the cup, the outer ring that carries the mating raceway. Outer Ring Width (C): 0.9375 in (23.813 mm).

No precision suffix — Precision Class: Not specified. A Timken precision class is carried by an explicit suffix such as -2 or -3, and neither appears on this part.

What these specs mean in practice:

Dynamic Load Rating: 113,000 N (25,500 lbf) at one million revolutions. Static Load Rating: 134,000 N (30,100 lbf). The 90-million-revolution Timken ratings are C90 29,400 N (6,610 lbf) radial and Ca90 15,400 N (3,460 lbf) thrust.

K Factor: 1.91. e Factor: 0.31. Y Factor: 1.96. The K factor is the ratio of radial to thrust capability, so a 1.91 puts this in the steeper end of the general-purpose inch range and gives it real combined-load capacity alongside its radial rating. The e factor sets the thrust-to-radial ratio above which the thrust term enters the equivalent load calculation.

G1 Factor: 39.5. G2 Factor: 10.5. Geometry Factor (Cg): 0.0808.

Mounting data:

Effective Center Location: -0.4 in (-10.2 mm), measured inside the cone backface. Max Shaft Fillet Radius: 0.140 in (3.600 mm). Max Housing Fillet Radius: 0.03 in (0.76 mm). Shaft Backing Shoulder Diameter, frontface (da): 1.69 in (43 mm). Shaft Backing Shoulder Diameter, backface (db): 1.95 in (49.5 mm). Housing Backing Shoulder Diameter, frontface (Da): 3.15 in (80.00 mm). Housing Backing Shoulder Diameter, backface (Db): 2.99 in (75.95 mm). Cage Location relative to backface (Aa): 0.07 in (1.8 mm). Cage Location relative to frontface (Ab): 0.05 in (1.3 mm).

The two fillet figures are the largest corner radii on the shaft and housing that the bearing corners will clear.

Quantity and configuration:

Unit Quantity: 1 Pc — one 3581 cone with its matching 3530 cup, forming one complete single-row bearing. A TS tapered roller bearing is normally mounted in opposing pairs on a shaft, with the second position taking its own bearing.

Interchange guidance:

Cross-references: SKF 3581/3530, FAG K3581-3530, NSK 3581/3530, NTN 4T-3581/3530, Koyo 3581/3530, Fersa 3581/3530, BCA / Bower 3581/3530, PEER 3581/3530. The cone and cup halves are matched: a 3581 cone runs against a 3530 cup, and the 3520 and 3525 cups are different outer rings.