51332-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 51332-M model number is decoded

The 51300 series order number 51332 M is a SKF single-direction thrust ball bearing for a 160 mm seat, built to ISO 104, with a flat housing seating surface, 160×270×87 mm boundary dimensions. Three separable parts make the set: the tight-bore shaft washer that locates on the shaft, the loose-bore housing washer in its register, and the ball-cage assembly; load is purely axial and acts in one direction. reading 51xxx as a code: the 1 after 5 identifies one load direction and a flat seat, and the next digit ranks the section 1 (light) to 4 (heavy) before the two-digit bore code. bore code 32 decodes to 160 mm (code 32 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the trailing M names a solid machined brass window cage centred on the balls rather than on a washer, the catalogue choice when size, speed or interrupted lubrication rules out sheet steel. Envelope 160×270×87 mm (6.299×10.63×3.425 in), 55.0 mm radial section, C 449 kN, C0 1660 kN, Pu 41.5 kN. reference speed 850 r/min (thermal) and limiting speed 1,200 r/min (mechanical), catalogue mass 21000 g. At the printed limiting speed of 1,200 r/min the mean pitch diameter dm ≈ 215.0 mm implies a dn value around 258k mm·r/min; the 850 r/min reference speed is the thermal-planning value under catalogue load. Minimum-load arithmetic: with dm ≈ 215.0 mm and factor A 14, Fam ≈ A·(n·dm/1000)² at the 850 r/min reference speed is about 467.6 kN for 51332 M; below that preload the balls skid and smear the tracks. Light-load floor: Pu = 41.5 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51332 M; the number is 9 % of the 449 kN dynamic rating. Mass and section check: 21000 g inside the 160×270×87 mm outline leaves a 55.0 mm radial section, and the 1660 kN static rating is 3.70× the dynamic rating — plan static safety and minimum preload against those figures. Speed band width for this size is 350 r/min between reference and limiting (1.41× ratio); lubrication, preload and heat removal decide where inside that band 51332 M can actually run. 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. At 21000 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 160 mm vertical shafts should use the actual M-execution weight, not the lighter pressed-cage catalogue value.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Heat the shaft washer to at most 120 °C for mounting, or press it via a sleeve on its ground bore — force applied through the housing washer or the ball set brinells the 449 kN track before first rotation.
• 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 87 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.
• The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 449/1660 kN and the available 270 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.
• 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 51332 against two-way load lifts the loose washer off its raceway.
• The 449/1660 kN figures belong to 51332 M specifically (the single flat brass execution of 51332); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record.