NKI7-12-TV-XL bearing: complete specifications & equivalents

Specification table

Source: catalog reference (HR1 2026-09-25) · extracted 2026-09-30

Parameters extracted from the official FAG Rolling Bearings catalogue (HR1 2026-09-25); FAG® is a trademark of Schaeffler Technologies AG & Co. KG, used here for identification only — mpnbase is not an authorized FAG/Schaeffler distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at schaeffler.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 NKI7-12-TV-XL model number is decoded

envelope 7×17×12 mm: 7 mm bore accepts a normal-tolerance machined shaft via the integral inner ring, with a thin 5.0 mm radial section packed with small-diameter needle rollers C is 5.3 kN and C0 5.5 kN at the 7 mm seat; the C/C0 ratio of 0.96 is characteristic of a needle bearing — high static rating relative to dynamic in a compact 17 mm outside diameter the fatigue load limit Cur is 0.94 kN, the limiting speed 29,500 r/min and the thermal reference speed 26,000 r/min; for small needle bearings the reference speed can exceed the kinematic limit, so the lower of the two governs the application dynamic capacity per millimetre of bore is 0.76 kN/mm and per millimetre of width 0.44 kN/mm — the reason 12 mm-wide needle bearings routinely replace much larger ball or roller positions mass is 13.7 g, just 0.07 g per mm² of projected 17×12 mm envelope, which keeps unbalanced forces low in fast-actuating linkages 7 mm bore and only 13.7 g: the smallest sizes demand accurate shaft geometry, because the 5.0 mm section leaves no tolerance for a soft or tapered seat This is the choice for OEM production on soft shafts: machine the 7 mm seat to the recommended tolerance, fit the bearing, and let the inner ring provide the precision raceway NKI7/12-TV-XL is supplied with a machined inner ring, so it mounts on an ordinary turned and ground shaft of normal tolerance — hardening the journal is not required X-life status (-XL) indicates the current Schaeffler premium execution at 7 mm bore; the 5.5 kN C0 rating reflects the improved rolling-contact geometry. With the -TV polyamide cage the rollers are positively separated, so the 7 mm bearing suits continuous rotation rather than the slow oscillating duty where cageless packs are chosen. Typical applications include agricultural machine pivots and linkages, hydraulic and pneumatic pump eccentrics and textile machine heald and cam shafts, where the 17 mm outside diameter and 5.3 kN dynamic rating match the duty. In agricultural machine pivots and linkages the unit fits a compact 7 mm seat, and in hydraulic and pneumatic pump eccentrics the 13.7 g mass keeps unbalanced forces low in fast linkages. Designers also specify it for textile machine heald and cam shafts, relying on the 12 mm width and the published 5.5 kN static rating. Adding an IR inner ring changes the envelope logic: the same outer assembly then fits a smaller shaft — recheck bore, clearance and ratings when substituting. Open ends draw contamination directly onto the needles; specify sealed or shielded positions in dusty environments rather than relying on grease alone.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Adding an IR inner ring changes the envelope logic: the same outer assembly then fits a smaller shaft — recheck bore, clearance and ratings when substituting.
• Open ends draw contamination directly onto the needles; specify sealed or shielded positions in dusty environments rather than relying on grease alone.
• Without an inner ring the shaft is the raceway: 58–64 HRC and a ground, polished journal are mandatory, not recommendations.