51417-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 51417-M model number is decoded

The 51400 series order number 51417 M is a SKF single-direction thrust ball bearing for a 85 mm seat, built to ISO 104, with a flat housing seating surface, 85×180×72 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 17 decodes to 85 mm (code 17 × 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 85×180×72 mm (3.346×7.087×2.835 in), 47.5 mm radial section, C 286 kN, C0 750 kN, Pu 24 kN. reference speed 1,200 r/min (thermal) and limiting speed 1,600 r/min (mechanical), catalogue mass 9450 g. Speed planning separates the two ceilings mechanically: the pressed brass cage and balls tolerate 1,600 r/min while thermal balance under catalogue load sets the 1,200 r/min reference; at dm ≈ 132.5 mm the corresponding dn is approximately 212k mm·r/min. Light-load floor: Pu = 24 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51417 M; the number is 8 % of the 286 kN dynamic rating. Capacity density: 286 kN C from 9.450 kg of bearing steel gives about 30.3 kN per kilogram; static density is correspondingly 79.4 kN/kg at C0 750 kN. Minimum-load arithmetic: with dm ≈ 132.5 mm and factor A 2.9, Fam ≈ A·(n·dm/1000)² at the 1,200 r/min reference speed is about 73.3 kN for 51417 M; below that preload the balls skid and smear the tracks. Sizing arithmetic on the 85 mm bore: 286 kN C over the 47.5 mm radial section gives 6.0 kN per section millimetre, and the 72 mm stack height is 1.52× that section — proportions typical of a 51400 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. At 9450 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 85 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

• The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 286/750 kN and the available 180 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.
• The 51417 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 85 mm shaft has to be carried by a radial bearing mounted alongside it.
• When the housing seat cannot be machined square to the 85 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51400 bearing.
• 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.
• Ordering discipline for 51417: the catalogue page quotes 51417 M and its 286/750 kN ratings as one exact article; bare-number substitutions from another series or brand need a fresh dimension and rating check, not a like-for-like assumption.