SKF7004CP4Super-Precision Angular Contact Ball Bearing – 20 mm ID, 42 mm OD, 12 mm Width, Open, 15° Contact Angle, P4A

Product Description

What this part is

SKF 7004CP4 single-row super-precision angular contact ball bearing. Bore 20 mm, outside diameter 42 mm, width 12 mm. ISO 70 series, size 7004, straight bore, open both faces.

Decoding the designation

Contact Angle: 15°, from the SKF C code. Design: high-capacity D execution. Precision Class: P4A, SKF’s super-precision grade. Cage Material: non-metallic. Series: ISO 70. Base Number: 7004. Current SKF catalogue form: 7004 CD/P4A.

Published ratings

Dynamic Load Rating Cr: 8.71 kN. Static Load Rating C0r: 4.3 kN. Fatigue load limit Pu: 0.18 kN. Limiting speed: 43,000 rpm on grease, 63,000 rpm on oil-air lubrication. Effective load centre a: 10.2 mm. Mass: 0.066 kg.

What these specs mean in practice

A 15° contact angle favours speed and radial load over thrust, which is what puts this bearing at 63,000 rpm under oil-air on a 20 mm bore. A non-metallic cage keeps cage mass and friction low at those speeds. P4A tolerances hold radial and axial runout tighter than P4, which shows up as lower running vibration and closer tool location on a grinding spindle.

Quantity and configuration

One bearing. The designation carries no preload or grouping code, so this is a clearance-set single with normal CN internal clearance.

Fitting notes

Shaft abutment diameter da: 23.2 mm minimum. Housing abutment diameter Da: 38.8 mm maximum. Db: 40 mm maximum. Housing fillet radius ra: 0.6 mm maximum, rb: 0.3 mm maximum. Oil-nozzle diameter dn: 28.4 mm.

Interchange guidance

Fafnir 2MM9104WI is the Timken cross on this envelope at the same 15° angle. FAG B7004-C-T-P4S shares the size and angle with a phenolic cage and P4S class, so it is a related size.