NSK7922CSN24TRDULP4YSuper Precision Angular Contact Bearing — 110 mm ID, 150 mm OD, 20 mm Width, Open, 15° Contact Angle, Ceramic Balls, Light Preload, 2 Pcs

Product Description

What this part is

NSK 7922CSN24TRDULP4Y, a universally matchable super-precision angular contact ball bearing with silicon nitride ceramic balls, supplied as two pieces. Bore: 110 mm. Outside diameter: 150 mm. Width: 20 mm per bearing. Series: 71900 (ISO 719 dimension series). Contact angle: 15°. Precision: P4Y. Country of origin as recorded: United Kingdom.

Decoding the designation

7922 is the ISO 719 dimension series at bore code 22, a narrower and thinner section than a 7022. C: 15° contact angle. SN24: silicon nitride ceramic balls. TR: outer-ring-guided phenolic resin cage, rated to 120 °C. DU: duplex universal matching, so any two bearings of this designation pair without a spacer. L: light preload. P4Y: ISO Class 4 running accuracy with special bore and outside diameter tolerances, giving closer shaft location and lower running vibration.

Ratings and speed

Basic dynamic load rating Cr: 65.5 kN. Basic static load rating C0r: 57.0 kN. Permissible axial load Pa: 42.4 kN. Limiting speed: 11,600 rpm on grease, 17,600 rpm on oil or oil-air. Effective load centre a: 27.4 mm. Axial rigidity at light preload: 138 N per micrometre. Preload force at light: 447 N. f0: 16.7.

What the ceramic balls buy

Silicon nitride balls run at about 40 percent of the density of steel, so centrifugal loading and ball-to-raceway contact stress fall at speed. Against the steel-ball 7922C on the identical envelope, the ceramic execution lifts the grease limiting speed from 8,900 to 11,600 rpm and the oil limiting speed from 13,500 to 17,600 rpm, raises axial rigidity, and drops the mass from 0.867 to 0.761 kg. Ceramic balls are also non-galling and hold their geometry better under marginal lubrication.

What these specs mean in practice

A 15° contact angle favours speed and radial rigidity over thrust capacity; a 25° bearing on the same envelope carries more thrust and turns slower. The 719 section is thin for its bore, which is what lets a 110 mm spindle keep a compact housing. Light preload removes axial play while keeping heat generation low.

Quantity and configuration

Two pieces, universally matched, 40 mm total width as a pair. Back-to-back carries thrust in both directions across a wide load-centre spread and takes moment loads. Face-to-face narrows that spread. Tandem doubles thrust capacity in one direction. Measured axial clearance in a back-to-back or face-to-face pair at light preload: minus 13 micrometres.

Fitting notes

Shaft abutment diameter da: 117 mm minimum. Housing abutment Da: 143 mm maximum, Db: 145 mm maximum. Ring chamfer r: 1.1 mm minimum, r1: 0.6 mm minimum. Shaft fillet radius ra: 1 mm maximum. Grease charge as published: 4.9 g per bearing. Both faces are open.

Interchange guidance

SKF 71922 CD/P4ADGA is the same envelope, contact angle and preload in a steel-ball execution. NSK 7922CTRDULP4Y is the steel-ball version of this exact designation — a related size rather than a substitution, because the speed rating and rigidity differ. NSK 7922CSN24TRDUMP4Y is the same ceramic bearing at medium preload.