51428-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 51428-M model number is decoded

51428 M is SKF's 140 mm-bore single-direction thrust ball bearing in the 51400 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 140×280×112 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 28 encode the bore as 140 mm (code 28 × 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 140×280×112 mm (5.512×11.024×4.409 in), 70.0 mm radial section, C 520 kN, C0 1730 kN, Pu 44 kN. reference speed 700 r/min (thermal) and limiting speed 1,000 r/min (mechanical), catalogue mass 34500 g. Speed band width for this size is 300 r/min between reference and limiting (1.43× ratio); lubrication, preload and heat removal decide where inside that band 51428 M can actually run. Sizing arithmetic on the 140 mm bore: 520 kN C over the 70.0 mm radial section gives 7.4 kN per section millimetre, and the 112 mm stack height is 1.60× that section — proportions typical of a 51400 thrust section. Section proportions: the 70.0 mm radial section compares with 140 mm of bore (section/bore ≈ 0.50) and the 112 mm height is 1.60× that section — the proportions that identify the 51400 envelope at a glance. Mass and section check: 34500 g inside the 140×280×112 mm outline leaves a 70.0 mm radial section, and the 1730 kN static rating is 3.33× the dynamic rating — plan static safety and minimum preload against those figures. Bore-to-OD planning: OD 280 over bore 140 is a 2.00× step for this size, and the 112 mm height gives a bore/height ratio of 1.25; use these ratios when the housing recess around the 140 mm shaft is the first constraint. 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. The M cage of 51428 M adds a small amount of mass and cage strength without changing the 140×280×112 mm ISO 104 envelope, so the pressed-cage execution drops into the same recess but should not be assumed equal under the 1,000 r/min ceiling.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Keep the applied thrust above Fam ≈ A·(n·dm/1000)² with the printed factor A 16; for 51428 M 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.
• 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 112 mm stack; thrust-ball bearings on horizontal shafts should have the shaft washer (the tight one) against the rotating element.
• 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 520 kN track before first rotation.
• The 51428 M is a pure axial bearing: it must never be subjected to radial load — any radial force on the 140 mm shaft has to be carried by a radial bearing mounted alongside it.
• Ordering discipline for 51428: the catalogue page quotes 51428 M and its 520/1730 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.