Single-direction thrust ball bearing

51236 M bearing

180 × 250 mm · dynamic rating 302 kN · static rating 1120 kN. Dimensions, load ratings, designation meaning, life estimates and equivalent parts.

51236 M specification

Designation51236 M
TypeSingle-direction thrust ball bearing
Series512 light-medium
Bore diameter d180 mm
Outside diameter D250 mm
Basic dynamic load rating C302 kN (302,000 N)
Basic static load rating C01120 kN (1,120,000 N)
Ratio C0/C3.71
Speed guide, grease lubrication1,600 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 51236 M means

CodeMeaning
512Single-direction thrust ball bearing, light-medium series (flat seat washers)
36 Mbore code "36 M" = 36 × 5 = 180 mm

Basic rating life of the 51236 M

Basic rating life is L10 = (C / P)p million revolutions, where P is the equivalent dynamic load and p = 3 (ball bearing). For a 51236 M with C = 302 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 60.4 kN on this bearing. Use the Load Calculator to work out P for your actual radial and axial loads.

Equivalents of the 51236 M

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 51236 M 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 51236 M is size 26 of 28 in the Rotec AI catalogue for the “512 light-medium” series. The next size down, the 51234 M, has a bore of 170 mm and a dynamic rating of 270 kN. The next size up, the 51238 M, has a bore of 190 mm and a rating of 332 kN (+10%).

51202 · 15 × 3251203 · 17 × 3551204 · 20 × 4051205 · 25 × 4751206 · 30 × 5251207 · 35 × 6251208 · 40 × 6851209 · 45 × 7351210 · 50 × 7851211 · 55 × 9051212 · 60 × 9551213 · 65 × 10051214 · 70 × 10551215 · 75 × 11051216 · 80 × 11551217 · 85 × 12551218 · 90 × 13551220 · 100 × 15051222 · 110 × 16051224 · 120 × 17051226 · 130 × 19051228 · 140 × 20051230 M · 150 × 21551232 M · 160 × 22551234 M · 170 × 24051236 M · 180 × 25051238 M · 190 × 27051240 M · 200 × 280
Check your 51236 M against your real loads and speed.

Common problems on bearings like the 51236 M

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 51236 M

What are the dimensions of a 51236 M bearing?

The 51236 M has a bore of 180 mm and an outside diameter of 250 mm. It is a single-direction thrust ball bearing. Series: 512 light-medium.

What is the load rating of a 51236 M bearing?

In the Rotec AI catalogue the 51236 M has a basic dynamic load rating C of 302 kN and a basic static load rating C0 of 1120 kN. Always confirm against the manufacturer's current catalogue.

What is the equivalent of a 51236 M bearing?

Brand equivalents for the 51236 M are not yet in the Rotec AI tables. Use the Cross-Reference tool to check other designations.