51336-M bearing: complete specifications & equivalents

Specification table

Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-28

Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018)); SKF® and SKF Explorer® are trademarks of AB SKF, used here for identification only — mpnbase is not an authorized SKF distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at skf.com.

Cross references & equivalents

Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.

How the 51336-M model number is decoded

Listed in SKF 17000 chapter 5, 51336 M is an ISO 104 single-direction thrust ball bearing, 180 mm bore and 300 mm OD on a flat housing seat, standing 95 mm high before installation. The bearing is delivered as separate, interchangeable parts: a ground-bore shaft washer, a loose-bore housing washer and the ball-cage assembly between them, designed for one axial load direction only. 51xxx breaks down as 5 for thrust ball, 1 for one load direction on a flat seat, a section digit 1–4 light-to-heavy, then the two-digit bore code. reading the ending 36: bore 180 mm (code 36 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. M-cage execution: brass machined from solid and ball-centred, giving heavier guidance than the standard pressed retainer at the top end of the thrust-ball range. Envelope 180×300×95 mm (7.087×11.811×3.74 in), 60.0 mm radial section, C 520 kN, C0 2000 kN, Pu 47.5 kN. reference speed 750 r/min (thermal) and limiting speed 1,100 r/min (mechanical), catalogue mass 28500 g. Rating split for documentation: dynamic 520 kN (L10 life), static 2000 kN (safety factor s0), fatigue limit 47.5 kN (adjusted life) — three different uses of three different numbers for 51336 M, none interchangeable with another. Light-load floor: Pu = 47.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51336 M; the number is 9 % of the 520 kN dynamic rating. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51336 M covers about 45,239 mm², distributing C0 2000 kN over a mean track circle of π·dm ≈ 754 mm. Speed band width for this size is 350 r/min between reference and limiting (1.47× ratio); lubrication, preload and heat removal decide where inside that band 51336 M can actually run. Sizing arithmetic on the 180 mm bore: 520 kN C over the 60.0 mm radial section gives 8.7 kN per section millimetre, and the 95 mm stack height is 1.58× that section — proportions typical of a 51300 thrust section. Machined-cage order-number note: the M brass cage is a one-piece ball-centred window cage, chosen at the heavy end of the section for speed and shock duty; it is heavier and stiffer than the pressed-steel execution of the smaller sizes and tolerates interrupted lubrication far better, which is why the catalogue restricts the M suffix to the large bores. The M cage of 51336 M adds a small amount of mass and cage strength without changing the 180×300×95 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,100 r/min ceiling.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• The three components are separable and interchangeable within the ISO 104 size, but keep this bearing's parts together in service and never combine washers from different manufacturers or a worn washer with a new ball set.
• The 51336 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 180 mm shaft has to be carried by a radial bearing mounted alongside it.
• On vertical shafts retain the loose housing washer positively with a cover or ring and verify the grease fill does not drain out of the 95 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.
• A 51-series bearing reacts thrust in one direction only — reversing positions need a mirrored single-direction pair or a 52-series double-direction unit; fitting a single 51336 against two-way load lifts the loose washer off its raceway.
• The 520/2000 kN figures belong to 51336 M specifically (the single flat brass execution of 51336); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record.