Single-direction thrust ball bearing

51306 bearing

30 × 60 mm · dynamic rating 35.8 kN · static rating 65.5 kN. Dimensions, load ratings, designation meaning, life estimates and equivalent parts.

51306 specification

Designation51306
TypeSingle-direction thrust ball bearing
Series513 medium
Bore diameter d30 mm
Outside diameter D60 mm
Basic dynamic load rating C35.8 kN (35,800 N)
Basic static load rating C065.5 kN (65,500 N)
Ratio C0/C1.83
Speed guide, grease lubrication5,300 rpm
Life exponent p3 (ball bearing)

Values come from the Rotec AI bearing catalogue and are indicative. Confirm against the manufacturer's current catalogue before ordering. Not every dimension (such as width) is listed here.

What the designation 51306 means

CodeMeaning
513Single-direction thrust ball bearing, medium series (flat seat washers)
06bore code "06" = 6 × 5 = 30 mm

Basic rating life of the 51306

Basic rating life is L10 = (C / P)p million revolutions, where P is the equivalent dynamic load and p = 3 (ball bearing). For a 51306 with C = 35.8 kN, the table shows what that gives at different load levels. It is the ISO 281 basic life only: it does not include lubrication, contamination, misalignment or reliability modifiers.

C / PP as share of CL10 (million rev)L10 at 1,500 rpmL10 at 3,000 rpm
333.3%27300150
520.0%1251,400690
812.5%5125,7002,800
128.3%1,72819,2009,600

For example, a C / P of 5 means the equivalent load is 7.16 kN on this bearing. Use the Load Calculator to work out P for your actual radial and axial loads.

Equivalents of the 51306

Brand-by-brand equivalents for this exact designation are not yet in the Rotec AI cross-reference tables. The Cross-Reference tool accepts SKF, FAG, NSK, NTN, Timken, Koyo and NRB designations, and shows what is catalogued.

Where the 51306 is used

Thrust ball / thrust roller bearings are chosen for: Predominantly axial load. Typical equipment: Vertical pumps, extruders, turbines, marine and heavy gear drives. Thrust roller for higher axial capacity and shock.

Other sizes in the same series

The 51306 is size 2 of 15 in the Rotec AI catalogue for the “513 medium” series. The next size down, the 51305, has a bore of 25 mm and a dynamic rating of 34.5 kN. The next size up, the 51307, has a bore of 35 mm and a rating of 49.4 kN (+38%).

51305 · 25 × 5251306 · 30 × 6051307 · 35 × 6851308 · 40 × 7851309 · 45 × 8551310 · 50 × 9551311 · 55 × 10551312 · 60 × 11051313 · 65 × 11551314 · 70 × 12551315 · 75 × 13551316 · 80 × 14051317 · 85 × 15051318 · 90 × 15551320 · 100 × 170
Check your 51306 against your real loads and speed.

Common problems on bearings like the 51306

Most field failures trace back to lubrication, contamination, fits and alignment rather than the bearing itself. These guides explain how to recognise and prevent them:

Subsurface-initiated fatigueLubrication failureRing creepFretting corrosionAll 23 failure modes

Questions about the 51306

What are the dimensions of a 51306 bearing?

The 51306 has a bore of 30 mm and an outside diameter of 60 mm. It is a single-direction thrust ball bearing. Series: 513 medium.

What is the load rating of a 51306 bearing?

In the Rotec AI catalogue the 51306 has a basic dynamic load rating C of 35.8 kN and a basic static load rating C0 of 65.5 kN. Always confirm against the manufacturer's current catalogue.

What is the equivalent of a 51306 bearing?

Brand equivalents for the 51306 are not yet in the Rotec AI tables. Use the Cross-Reference tool to check other designations.