51216-SKF 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 51216-SKF model number is decoded

The 51200 series order number 51216 is a SKF single-direction thrust ball bearing for a 80 mm seat, built to ISO 104, with a flat housing seating surface, 80×115×28 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 16 decodes to 80 mm (code 16 × 5) under the same 00/01/02/03-exception, ×5 rule SKF uses across its coded bearing ranges. the suffix-free listing carries the catalogue default: a pressed (stamped sheet-steel) ball-cage assembly, light and quiet, used across the small and medium sizes. Envelope 80×115×28 mm (3.15×4.528×1.102 in), 17.5 mm radial section, C 76.1 kN, C0 208 kN, Pu 7.65 kN. reference speed 2,400 r/min (thermal) and limiting speed 3,400 r/min (mechanical), catalogue mass 910 g. Rating split for documentation: dynamic 76.1 kN (L10 life), static 208 kN (safety factor s0), fatigue limit 7.65 kN (adjusted life) — three different uses of three different numbers for 51216, none interchangeable with another. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51216 covers about 5,360 mm², distributing C0 208 kN over a mean track circle of π·dm ≈ 306 mm. Sizing arithmetic on the 80 mm bore: 76.1 kN C over the 17.5 mm radial section gives 4.3 kN per section millimetre, and the 28 mm stack height is 1.60× that section — proportions typical of a 51200 thrust section. Load balance: C0 208 kN against C 76.1 kN gives a 2.73 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 7.65 kN enters the adjusted-life check. Static-first selection data: 208 kN C0 spread across the 28 mm stack gives 7.4 kN of static rating per height millimetre, and the 910 g mass/C0 ratio is about 4 g per static kN — crane-hook and screw positions are normally sized on these two figures. Execution note for this order number: the flat housing seating surface must be machined square to the shaft axis and supported across the full washer face — unlike the sphered 53-series execution this pressed-cage 51-series bearing has no self-aligning capability at all, so seat squareness is checked at mounting, not compensated in service. Inspection after removal of a 28 mm-high stack means checking both washer faces: the loose housing washer often shows the first false-brinell marks under machine vibration even though the tight shaft washer carries the rotating load of 76.1 kN C.

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 28 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 76.1/208 kN and the available 115 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.
• Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 0.22; for 51216 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.
• 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.
• Catalogue ratings are SKF PUB BU/P1 17000 figures for 51216 as the single flat pressed steel execution; other order numbers of the 51216 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing.