Timken36690-3/36620B-3Complete Tapered Roller Bearing Cone and Cup Set 5-3/4 in Bore x 7-5/8 in OD Class 3 Precision 36600 Series — Both Halves Included

Product Description

What this part is

This is a complete single-row tapered roller bearing: the 36690 cone paired with the 36620-B cup, from Timken’s 36600 inch series, 5.7500 in (146.050 mm) bore by 7.6250 in (193.675 mm) outside diameter, supplied to Class 3 precision on both halves.

A tapered roller bearing is built as two separately numbered halves. The cone is the inner ring complete with its tapered roller set and cage, and it presses onto the shaft. The cup is the outer ring with the tapered raceway ground into its bore, and it presses into the housing. This listing supplies both.

What is and is not included

Both halves are included: the 36690 cone with its rollers and cage, and the 36620-B cup. The set does not include shims, lock nuts, seals or a housing. Endplay shimming is machine-specific.

Decoding the designation

36690 is the cone number from the 36600 inch series. In Timken’s inch numbering the cone and cup are numbered separately within a common series: 36690 and 36691 are cones, 36620 is a cup. The cone number selects the bore, giving the 5.7500 in / 146.050 mm shaft fit, and the cup number fixes the 7.6250 in / 193.675 mm housing fit.

B in 36620B is a Timken design-revision letter on the cup. Timken’s catalogue lists the 36690 / 36620-B pairing under TSF, Tapered Single with Flange, and publishes a flange outside diameter (D1) of 7.7772 in / 197.541 mm with a flange width (C2) of 0.1563 in / 3.97 mm. A flanged cup locates axially against the face of the housing rather than against a shoulder machined inside the bore, which gives a repeatable seat in a through-bored or thin-walled housing. A flanged cup does not drop into a housing bored for a plain cup.

−3 on both numbers denotes Timken precision Class 3. The notations 36690-3, 36690 #3 and 36690 *3 all mean the same thing, as do 36620B-3, 36620B #3 and 36620B *3. K-36690 and K-36620-B are Timken component-order designations for the cone and the cup ordered as loose components.

What Class 3 precision buys you

Timken supplies inch tapered roller bearings in graded precision classes: Class 4 is the standard commercial grade, then Class 3, Class 0, Class 00 and finer. Each step up tightens the tolerances on bore, outside diameter and width, and on the radial and axial runout of the ground raceways.

A Class 3 bearing runs truer than a standard bearing in the same envelope, on the shaft and in the housing alike. It is specified where runout translates directly into a product-quality problem: machine tool spindles, precision gearboxes and index drives, printing and converting rolls, gear grinders, paper machine positions. It costs more than a standard bearing and it is stocked far less widely.

A standard 36690/36620B fits where a Class 3 set is called for, and it does not run the same. Both rings in this set are Class 3. Precision class governs runout on each ring independently, so a Class 3 cone paired with a standard cup gives the runout of the standard cup. The specific Class 3 runout limits are set by Timken’s precision tolerance tables.

Published ratings

The figures below are Timken’s own published data for the complete 36690 / 36620-B single-row assembly, which is what this listing is. A load rating belongs to the pair, because capacity is a property of the roller set running between both races.

Cone part number: 36690. Cup part number: 36620-B. Series: 36600. Bore (d): 5.7500 in / 146.050 mm. Outside diameter (D): 7.6250 in / 193.675 mm. Cone inner ring width (B): 1.1250 in / 28.575 mm. Cup outer ring width (C): 0.9063 in / 23.020 mm. Outer ring flange outside diameter (D1): 7.7772 in / 197.541 mm. Outer ring flange width (C2): 0.1563 in / 3.97 mm. Dynamic radial load rating C1 (1 million revolutions, ISO method): 44,200 lbf / 196,000 N. Dynamic radial load rating C90 (90 million revolutions, Timken method): 11,400 lbf / 50,900 N. Dynamic axial rating Ca90: 7,220 lbf / 32,100 N. Static radial load rating C0: 88,600 lbf / 394,000 N. e factor 0.37, K factor 1.59, Y factor 1.63. G1 factor 366, G2 factor 121, geometry factor Cg 0.177.

What these specs mean in practice

The K factor of 1.59 is the ratio of radial to thrust capability set by the cup angle: a higher K means a shallower cup angle and a bearing that is radially strong and comparatively thrust-weak. At 1.59 the 36600 series sits in the middle of the tapered roller range, carrying a useful axial component alongside its radial load. That is the load mix a gear-driven shaft produces, which is why the series appears in gearbox, pinion and roll positions rather than in pure thrust duty.

The e factor of 0.37 is the threshold in the equivalent-load equation: below an axial-to-radial load ratio of 0.37 the thrust component drops out of the calculation, above it the equation changes form. With e = 0.37, K = 1.59 and Y = 1.63 published above alongside C1, C90, Ca90 and C0, a bearing life calculation on this position can be run from this page alone.

Quantity and configuration

Each piece is one complete cone-and-cup set: one cone plus one cup, making one whole bearing.

Mounting data

Shaft backing shoulder diameter, frontface (da): 6.02 in / 153 mm; backface (db): 6.1 in / 155 mm. Housing backing shoulder diameter, frontface (Da): 7.50 in / 190.5 mm. Maximum shaft fillet radius cleared: 0.06 in / 1.5 mm. Maximum housing fillet radius cleared: 0.06 in / 1.5 mm. Effective centre location: 0.19 in / 4.8 mm. Cage location relative to frontface (Ab): 0.13 in / 3.3 mm; relative to backface (Aa): 0.04 in / 1 mm.

The cone presses onto the shaft and the cup into the housing. Tapered roller bearings carry no built-in internal clearance: the operating endplay or preload is created at assembly by how far the cone is drawn up against the cup, and that setting governs bearing life more than any other single variable. In a precision position the machine builder specifies it tightly.

Interchange guidance

36690 and 36620 are industry-standard inch designations rather than proprietary Timken codes, so both halves are manufactured by several bearing makers and a 36690/36620B set from any source is dimensionally interchangeable. The precision class is not part of the base number, so a plain 36690/36620B from any maker is a standard-class set and is not equivalent to this 36690-3 / 36620B-3.

Cross-references: 36690/36620B, 36690-3/36620B-3, 36690/36620-B, 36690 36620B, 36690-36620B, 36690 #3 36620B #3, 36690 *3 36620B *3, K-36690/K-36620-B, K36690 K36620B, 36690/36620. Cone forms: 36690, 36-690, 36690-3, K-36690. Cup forms: 36620B, 36620-B, 36620B-3, K-36620-B, 36620. Sibling cone: 36691. Related cup forms: 36620D and 36620DC double cups, 36620P. Related assemblies: 36691/36620, 36690/36620D, 36690/36620DC.

Central Surplus also stocks the two halves separately, both Class 3: the Timken 36690 cone under SKU B-BS3#LAQ8WA and the Timken 36620B-3 cup under SKU B-BO4#LMZ2UA.