51180-F 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 51180-F model number is decoded

Listed in SKF 17000 chapter 5, 51180 F is an ISO 104 single-direction thrust ball bearing, 400 mm bore and 480 mm OD on a flat housing seat, standing 65 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 80: bore 400 mm (code 80 × 5) for this single-direction size, via the standard exceptions 00/01/02/03 and ×5 above them. F-cage execution: a solid machined steel ball-centred retainer for the biggest thrust-ball sizes, where rigidity and cage guidance dominate over the lightness of sheet steel. Envelope 400×480×65 mm (15.748×18.898×2.559 in), 40.0 mm radial section, C 403 kN, C0 2280 kN, Pu 40.5 kN. reference speed 700 r/min (thermal) and limiting speed 1,000 r/min (mechanical), catalogue mass 24000 g. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51180 F covers about 55,292 mm², distributing C0 2280 kN over a mean track circle of π·dm ≈ 1,382 mm. Mass and section check: 24000 g inside the 400×480×65 mm outline leaves a 40.0 mm radial section, and the 2280 kN static rating is 5.66× the dynamic rating — plan static safety and minimum preload against those figures. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 27 at the 1,000 r/min limiting speed raises the required axial preload to about 5227.2 kN; the reference-speed value 2561.3 kN is the thermal design point. At the printed limiting speed of 1,000 r/min the mean pitch diameter dm ≈ 440.0 mm implies a dn value around 440k mm·r/min; the 700 r/min reference speed is the thermal-planning value under catalogue load. Pitch-diameter arithmetic: dm = (400+480)/2 = 440.0 mm; at the 1,000 r/min limiting speed that corresponds to roughly 440k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Large-size execution note: the F machined steel cage exists because the ball complement and pitch diameter of the biggest 512-series sizes are beyond pressed-cage guidance; the steel cage is machined from solid, ball-centred, and its heavier mass must be supported by genuine oil or grease flow at start-up — never mount an F bearing dry for a trial rotation. Mounting note for the 65 mm F stack: induction-heat the shaft washer only — the machined steel cage rides the balls and must never be tapped, and first rotation should be a slow unloaded bedding run before the working thrust goes on.

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 403/2280 kN and the available 480 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 51180 against two-way load lifts the loose washer off its raceway.
• The 51180 F is a pure axial bearing: it must never be subjected to radial load — any radial force on the 400 mm shaft has to be carried by a radial bearing mounted alongside it.
• Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 400 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.
• Ordering discipline for 51180: the catalogue page quotes 51180 F and its 403/2280 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.