51126 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 51126 model number is decoded

51126 is SKF's 130 mm-bore single-direction thrust ball bearing in the 51100 series to the ISO 104 dimension plan, with a flat housing seating surface, measuring 130×170×30 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 26 encode the bore as 130 mm (code 26 × 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 130×170×30 mm (5.118×6.693×1.181 in), 20.0 mm radial section, C 119 kN, C0 440 kN, Pu 13.4 kN. reference speed 1,900 r/min (thermal) and limiting speed 2,600 r/min (mechanical), catalogue mass 1850 g. Preload at the mechanical ceiling: repeating Fam ≈ A·(n·dm/1000)² with factor A 0.94 at the 2,600 r/min limiting speed raises the required axial preload to about 143.0 kN; the reference-speed value 76.4 kN is the thermal design point. Mass and section check: 1850 g inside the 130×170×30 mm outline leaves a 20.0 mm radial section, and the 440 kN static rating is 3.70× the dynamic rating — plan static safety and minimum preload against those figures. At the printed limiting speed of 2,600 r/min the mean pitch diameter dm ≈ 150.0 mm implies a dn value around 390k mm·r/min; the 1,900 r/min reference speed is the thermal-planning value under catalogue load. Sizing arithmetic on the 130 mm bore: 119 kN C over the 20.0 mm radial section gives 6.0 kN per section millimetre, and the 30 mm stack height is 1.50× that section — proportions typical of a 51100 thrust section. Speed band width for this size is 700 r/min between reference and limiting (1.37× ratio); lubrication, preload and heat removal decide where inside that band 51126 can actually run. 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 130 mm size the pressed cage and separable washers make the bearing interchangeable across brands on the ISO 104 plan, but the SKF ratings 119/440 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

• The 51126 is a pure axial bearing: it must never be subjected to radial load — any radial force on the 130 mm shaft has to be carried by a radial bearing mounted alongside it.
• The third digit grades the section: 511 light, then 512, 513 and 514 progressively taller and heavier at the same bore — select from 119/440 kN and the available 170 mm OD, never substitute a lighter series for a heavier one without rechecking C and C0.
• 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.
• 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 119 kN track before first rotation.
• Catalogue ratings are SKF PUB BU/P1 17000 figures for 51126 as the single flat pressed steel execution; other order numbers of the 51126 size are different products and may carry different ratings or seating geometry — always quote the full designation when purchasing.