SKF71912CDP4ATGASuper Precision Angular Contact Ball Bearing Matched Set of 3 – 60 mm ID, 85 mm OD, 13 mm Width, Open, 15° Contact Angle, Extra Light Preload, Universally Matchable

Product Description

What this part is

SKF 71912-CD/P4ATGA super-precision angular contact ball bearings, supplied as a matched set of three. Series: 719, extra light section. Bore: 60 mm. Outside Diameter: 85 mm. Width: 13 mm per bearing. Open on both faces, machined fabric-reinforced phenolic resin cage, steel balls on steel raceways. Searchable forms: 71912 CD/P4ATGA, 71912CDP4ATGA, 71912-CD-P4A-TGA, 71912CD/P4A-TGA, 7912.

Decoding the designation

Contact Angle: 15°. Precision Class: P4A — ABEC 7 dimensional tolerance with running accuracy held to ABEC 9. Set size: three bearings. Preload: extra light. Universally matchable grinding. Cage: machined phenolic resin, rated for continuous service to 120°C.

What these specs mean in practice

A 15° contact angle favours speed and radial stiffness over thrust capacity, which is why this design dominates high-speed grinding and milling spindles. The 719 section is the thinnest of the super-precision envelopes, giving a large bore in a small outside diameter. Per bearing: Dynamic Load Rating 19.9 kN (4 474 lbf), Static Load Rating 15.3 kN (3 440 lbf). Limiting speed: 15 000 r/min. Extra light preload keeps heat generation and friction low while still removing internal clearance.

Quantity and configuration

Three bearings. Unit Quantity: 3 Pcs. Universally matchable: the rings are ground so the bearings reach the specified extra light preload when clamped together, which allows the three to be built as back-to-back, face-to-face or tandem combinations. Open bearings, lubricated on installation with grease or oil.

Fitting notes

All three bearings are clamped against a common shoulder and locknut for the ground preload to take effect. The phenolic cage sets the temperature ceiling at 120°C. Preloaded bearings run without internal clearance, so shaft and housing seats are held to super-precision tolerances.

Interchange guidance

The 15° Fafnir equivalent on this envelope is the 2MM9312WI series. Fafnir 3MM9312WI-TUL is a related size on the same 719 envelope with a 25° contact angle. SKF 71912 ACD/P4ATGA is a related size at 25°. SKF 71912 CD/P4ATGB is a related size at medium preload.