51176-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 51176-F model number is decoded

Listed in SKF 17000 chapter 5, 51176 F is an ISO 104 single-direction thrust ball bearing, 380 mm bore and 460 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 76: bore 380 mm (code 76 × 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 380×460×65 mm (14.961×18.11×2.559 in), 40.0 mm radial section, C 397 kN, C0 2200 kN, Pu 40 kN. reference speed 750 r/min (thermal) and limiting speed 1,000 r/min (mechanical), catalogue mass 23000 g. At the printed limiting speed of 1,000 r/min the mean pitch diameter dm ≈ 420.0 mm implies a dn value around 420k mm·r/min; the 750 r/min reference speed is the thermal-planning value under catalogue load. Section proportions: the 40.0 mm radial section compares with 380 mm of bore (section/bore ≈ 0.11) and the 65 mm height is 1.63× that section — the proportions that identify the 51100 envelope at a glance. Sizing arithmetic on the 380 mm bore: 397 kN C over the 40.0 mm radial section gives 9.9 kN per section millimetre, and the 65 mm stack height is 1.63× that section — proportions typical of a 51100 thrust section. Pitch-diameter arithmetic: dm = (380+460)/2 = 420.0 mm; at the 1,000 r/min limiting speed that corresponds to roughly 420k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51176 F covers about 52,779 mm², distributing C0 2200 kN over a mean track circle of π·dm ≈ 1,319 mm. 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. The F execution appears only at the 380 mm top end of the range: the 460 mm OD ball complement is large enough that cage centrifugal forces dictate a machined guide, which is also why the 2200 kN C0 figure dominates selection of this order number.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• 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 65 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.
• Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 380 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.
• 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.
• Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 25; for 51176 F a spring preload or the rotor weight is part of the selection at light load and high speed, because unloaded balls skid rather than roll.
• Catalogue ratings are SKF PUB BU/P1 17000 figures for 51176 F as the single flat machined steel execution; other order numbers of the 51176 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing.