51313-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 51313-SKF model number is decoded

51313 is SKF's 65 mm-bore single-direction thrust ball bearing in the 51300 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 65×115×36 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 13 encode the bore as 65 mm (code 13 × 5), the standard SKF bore-code rule shared with radial bearings. with no cage suffix this is the standard execution with a stamped sheet-steel ball-cage assembly (pressed cage) — the light, quiet and economical cage for small and medium thrust-ball sizes. Envelope 65×115×36 mm (2.559×4.528×1.417 in), 25.0 mm radial section, C 106 kN, C0 240 kN, Pu 8.8 kN. reference speed 2,000 r/min (thermal) and limiting speed 3,000 r/min (mechanical), catalogue mass 1500 g. Bore-to-OD planning: OD 115 over bore 65 is a 1.77× step for this size, and the 36 mm height gives a bore/height ratio of 1.81; use these ratios when the housing recess around the 65 mm shaft is the first constraint. Washer-annulus check: the π/4·(D²−d²) contact annulus of 51313 covers about 7,069 mm², distributing C0 240 kN over a mean track circle of π·dm ≈ 283 mm. Load balance: C0 240 kN against C 106 kN gives a 2.26 ratio — thrust ball bearings are chosen on static rating and F_a/C0 far more often than on L10 life, while Pu 8.8 kN enters the adjusted-life check. Selection figures for 51313: the C0/C ratio is 2.26, Pu 8.8 kN is about 8 % of C, and the catalogue mass works out to roughly 23 g per millimetre of bore; the printed minimum-load factor is A 0.3. Mass and section check: 1500 g inside the 65×115×36 mm outline leaves a 25.0 mm radial section, and the 240 kN static rating is 2.26× the dynamic rating — plan static safety and minimum preload against those 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. On this 65 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 106/240 kN are this catalogue's figures — confirm the replacement order's ratings rather than swapping on envelope alone.

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 106 kN track before first rotation.
• 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.
• Identify the washers before fitting: the shaft washer has the ground, smaller bore and takes an interference fit on the 65 mm shaft, while the housing washer bore is larger and runs loose; swapping them locks the ball set and burns the tracks.
• The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 106/240 kN and the available 115 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.
• The 106/240 kN figures belong to 51313 specifically (the single flat pressed steel execution of 51313); suffixed, sphered and counterpart-series order numbers are separate articles, so write the complete designation on the order and the maintenance record.