53324-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 53324-M model number is decoded

53324 M is SKF's 120 mm-bore single-direction thrust ball bearing in the 53300 series to the ISO 104 dimension plan, with a sphered housing washer paired to a U seat washer, measuring 120×210×74.1 mm U 324 seat washer companion included in the mounted H1 dimension. 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 53xxx designation the 3 marks a single-direction bearing whose housing washer has a sphered (convex) seating surface, intended to run against the matching U seat washer; the third digit 2–4 grades the section. the final two digits 24 encode the bore as 120 mm (code 24 × 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 120×210×74.1 mm (4.724×8.268×2.917 in), 45.0 mm radial section, C 325 kN, C0 980 kN, Pu 28.5 kN. Mounted height H1 80 mm includes the U 324 seat washer; the bearing alone is 74.1 mm high. reference speed 1,000 r/min (thermal) and limiting speed 1,400 r/min (mechanical), catalogue mass 12500 g. Stack/annulus proportions: the 74.1 mm axial stack over the 23,326 mm² washer annulus gives 3.18 mm of height per annular square millimetre ×10⁻³, and at 12500 g the bearing holds about 78.4 kN of C0 per kilogram. Selection figures for 53324 M: the C0/C ratio is 3.02, Pu 28.5 kN is about 9 % of C, and the catalogue mass works out to roughly 104 g per millimetre of bore; the printed minimum-load factor is A 5. Sizing arithmetic on the 120 mm bore: 325 kN C over the 45.0 mm radial section gives 7.2 kN per section millimetre, and the 74.1 mm stack height is 1.65× that section — proportions typical of a 53300 thrust section. Bore-to-OD planning: OD 210 over bore 120 is a 1.75× step for this size, and the 74.1 mm height gives a bore/height ratio of 1.62; use these ratios when the housing recess around the 120 mm shaft is the first constraint. Speed planning separates the two ceilings mechanically: the pressed brass cage and balls tolerate 1,400 r/min while thermal balance under catalogue load sets the 1,000 r/min reference; at dm ≈ 165.0 mm the corresponding dn is approximately 231k mm·r/min. Heavy sphered-execution note: this M order number combines the machined brass ball-centred cage with the sphered housing washer and its U seat washer; it is the large-bore answer for hook blocks and pivots whose fabricated structure deflects — verify the spherical pair swivels freely under a light preload before the working load goes on. Under 980 kN static load the spherical interface of 53324 M must stay lubricated with a grease that does not separate at rest; a dry sphered contact under hook-block shock frets even though the ball tracks remain unworn.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• The self-aligning feature is checked at commissioning by hand: with the shaft under no load the assembly must swivel and settle; a stiff spherical seat means dirt, a mismatched U washer, or a register bored off-axis.
• Replacement orders must list both 53324 M and U 324: the seat washer is a separate article, and a U washer of the wrong size narrows the contact band of the 980 kN static-rated set.
• Keep the sphered interface clean and lightly greased: scale, paint or grit between the washer back and U 324 locks the aligning function and frets under load; re-grease the contact at every overhaul.
• Minimum axial load still applies with factor A 5: a self-aligning seat does not prevent ball skidding, so provide spring preload or sufficient rotor weight at light load and speed.
• Ordering discipline for 53324: the catalogue page quotes 53324 M plus U 324 and its 325/980 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.