YAR-203-12-2F 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 YAR-203-12-2F model number is decoded

The YAR2 series order number YAR 203/12-2F is a SKF insert bearing (Y-bearing) for a 12 mm shaft: grub-screw insert bearing with the inner ring extended on both sides, built to the ISO 15 diameter-series envelope with a sphered OD of 40 mm. Inside is a sealed deep-groove ball set with an extended inner ring, two set screws 120 deg apart doing the shaft locking, and the sphered outer ring providing the unit's static alignment pivot. reading the YAR basic designation: set-screw shaft locking with the screws spaced 120 deg apart; YAR carries the symmetric, both-sides-extended inner ring. the slash tail names a non-standard metric bore directly: YAR 203/12 is the 12 mm bore execution of the size series. the -2F external design pairs a nitrile contact seal with a plain sheet-steel thrower on both sides — a two-stage exclusion chain of flinger first, sealing lip second, typical of farm and conveyor duty. Envelope 12x40x27.4 mm (0.472x1.575x1.079 in), outer ring 12 mm wide, C 9.56 kN, C0 4.75 kN, Pu 0.2 kN. The catalogue publishes a single speed ceiling, the limiting speed: 9,500 r/min; mass 120 g. Mass-to-load ratio for YAR-203-12-2F: 12.552 g of catalogue mass per rated kN of C, and 10 g per millimetre of bore — useful when comparing executions of the same 12x40 mm envelope on the drawing. Outer-vs-overall width: the outer ring is 12 mm wide inside the 27.4 mm total, so the extended inner ring accounts for 0.562 of the overall width (7.7 mm of axial projection per side). Bore-to-OD planning: OD 40 over bore 12 is a 3.333x step, while bore/overall-width gives 0.438; the spherical seat in the matching Y-housing must be specified to the 40 mm OD, not to a cylindrical housing bore. Rating split for the maintenance file: dynamic 9.56 kN (L10), static 4.75 kN (s0 shock check), fatigue 0.2 kN (adjusted life) — three separate uses for YAR 203/12-2F, none interchangeable with another. Fillet discipline: the printed r_min 0.3 mm limit means shaft and housing fillets must stay under that radius; a fillet that bottoms the 12x40 mm insert on its chamfer tilts the whole spherical seat. Both-sides sealed order-number note: the two set screws clamp through dimpled recesses in the extended inner ring; tighten alternately to the catalogue procedure and retighten after the first run-in period, because the -2F flingers keep dust out but cannot compensate for a screw that walked loose. Service tip for YAR-203-12-2F: dimpled or drilled shaft spots under the screw points are sometimes specified on shock duty, but the standard mounting relies on point indentation alone — never substitute longer screws that reach the 14 mm radial section.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Do not specify the 12 mm grub-screw insert for a shaft harder than about 45 HRC without dimples: the screw points skate on hard surfaces and the unit creeps regardless of tightening torque.
• Replacement discipline: a YAR insert is not interchangeable with an eccentric-collar unit of the same envelope — the shaft may need spot-facing or collar space that does not exist.
• The 15.9 mm s1 dimension is the screw seating geometry inside the 15.4 mm of extended inner ring; a shaft step that crowds that side prevents the screws reaching the shaft squarely.
• Catalogue ratings belong to YAR 203/12-2F as the grub two f execution; other order numbers of the YAR 203/12 size are different articles (open vs sealed, plain vs rubberized flinger, stainless vs carbon steel) and may carry different ratings or speeds — always quote the full designation.