51416-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 51416-M model number is decoded

51416 M is SKF's 80 mm-bore single-direction thrust ball bearing in the 51400 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 80×170×68 mm. The separable set comprises a shaft washer (ground bore, tight fit on the shaft), a loose-bore housing washer and one ball-cage assembly, reacting axial force in one direction and carrying no radial load. in the 51xxx designation the first 1 marks a single-direction bearing with a flat housing seating surface; the third digit 1–4 grades the dimension series from the light 511 section through the heavy 514 section. the final two digits 16 encode the bore as 80 mm (code 16 × 5), the standard SKF bore-code rule shared with radial bearings. suffix M identifies a one-piece machined brass cage, ball-centred: the large-size and heavy-section option for higher speeds, shock loads and thin-film lubrication where a pressed cage would distort. Envelope 80×170×68 mm (3.15×6.693×2.677 in), 45.0 mm radial section, C 302 kN, C0 750 kN, Pu 25 kN. reference speed 1,200 r/min (thermal) and limiting speed 1,700 r/min (mechanical), catalogue mass 7950 g. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 2.3 at the 1,700 r/min limiting speed raises the required axial preload to about 103.9 kN; the reference-speed value 51.7 kN is the thermal design point. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51416 M covers about 17,671 mm², distributing C0 750 kN over a mean track circle of π·dm ≈ 393 mm. Minimum-load arithmetic: with dm ≈ 125.0 mm and factor A 2.3, Fam ≈ A·(n·dm/1000)² at the 1,200 r/min reference speed is about 51.7 kN for 51416 M; below that preload the balls skid and smear the tracks. Sizing arithmetic on the 80 mm bore: 302 kN C over the 45.0 mm radial section gives 6.7 kN per section millimetre, and the 68 mm stack height is 1.51× that section — proportions typical of a 51400 thrust section. Imperial cross-check for procurement drawings: 3.15 in bore, 6.693 in OD, 2.677 in height, and the 7950 g catalogue mass converts to 7.950 kg (280.4 oz). 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 7950 g the machined brass cage represents a meaningful fraction of total mass; balancing checks on high-speed 80 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 51416 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 80 mm shaft has to be carried by a radial bearing mounted alongside it.
• 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.
• 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 51416 against two-way load lifts the loose washer off its raceway.
• 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 302 kN track before first rotation.
• Catalogue ratings are SKF PUB BU/P1 17000 figures for 51416 M as the single flat brass execution; other order numbers of the 51416 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing.