51314-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 51314-SKF model number is decoded

The 51300 series order number 51314 is a SKF single-direction thrust ball bearing for a 70 mm seat, built to ISO 104, with a flat housing seating surface, 70×125×40 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 14 decodes to 70 mm (code 14 × 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 70×125×40 mm (2.756×4.921×1.575 in), 27.5 mm radial section, C 135 kN, C0 320 kN, Pu 11.8 kN. reference speed 1,900 r/min (thermal) and limiting speed 2,600 r/min (mechanical), catalogue mass 2000 g. Bore-to-OD planning: OD 125 over bore 70 is a 1.79× step for this size, and the 40 mm height gives a bore/height ratio of 1.75; use these ratios when the housing recess around the 70 mm shaft is the first constraint. Light-load floor: Pu = 11.8 kN is the equivalent-load threshold below which the SKF adjusted-life equation credits very long life for 51314; the number is 9 % of the 135 kN dynamic rating. Pitch-diameter arithmetic: dm = (70+125)/2 = 97.5 mm; at the 2,600 r/min limiting speed that corresponds to roughly 254k mm·r/min, the figure used when comparing cage speed demand across the thrust-ball series. Capacity density: 135 kN C from 2.000 kg of bearing steel gives about 67.5 kN per kilogram; static density is correspondingly 160.0 kN/kg at C0 320 kN. Stack/annulus proportions: the 40 mm axial stack over the 8,423 mm² washer annulus gives 4.75 mm of height per annular square millimetre ×10⁻³, and at 2000 g the bearing holds about 160.0 kN of C0 per kilogram. 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 40 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 135 kN C.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• 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 135 kN track before first rotation.
• 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 40 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.
• When the housing seat cannot be machined square to the 70 mm shaft, the sphered 53-series execution of this size with its U seat washer is the self-aligning counterpart of this flat 51300 bearing.
• 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 51314 against two-way load lifts the loose washer off its raceway.
• The 135/320 kN figures belong to 51314 specifically (the single flat pressed steel execution of 51314); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record.