Fafnir3MM204WI CR DULSuper Precision Spindle Angular Contact Ball Bearing 20x47x14 mm, 25 Degree Contact Angle, Phenolic Outer-Land-Riding Cage, Duplex Universal Light Preload, ISO P4S

Product Description

What this part is:

The Fafnir 3MM204WICRDUL is a super-precision spindle angular contact ball bearing, 20 mm bore, 47 mm outside diameter, 14 mm width, 25° contact angle, ground to duplex universal light preload. Mounted as a back-to-back pair the set occupies 28 mm of shaft length. Fafnir is part of Timken, and the MM-prefix spindle range remains in current production.

Decoding the designation:

3MM — super-precision spindle bearing at the high contact angle, 25°. Timken’s catalogue footnote states that 3 is the Timken designation and E is the ISO designation for 25°; 2MM is the corresponding 15° series.

204 — 72-series bore code, 20 mm bore in the 47 mm outside diameter envelope.

WI — Timken angular contact geometry code: full shoulders both sides of the inner ring and a low shoulder on the outer ring, carrying thrust in one direction in a non-separable bearing.

CR — composition (phenolic) cage riding on the outer-ring land, standard service to 93°C.

DUL — flush-ground duplex universal pair at light preload; DUM is medium, DUH heavy, DUX extra-light.

Specifications:

Bore: 20 mm. Outside Diameter: 47 mm. Width: 14 mm. Assembled duplex pair width: 28 mm. Contact Angle: 25°. Precision Class: P4S. Running accuracy meets ABEC 9 (ISO P2) levels while other features conform to ABEC 7 (ISO P4). Cage Material: Phenolic. Cage riding: outer-ring land. Cage service temperature limit: 93°C. Rolling Elements: 10 balls, 7.94 mm diameter. Dynamic Load Rating: 15,500 N (3,490 lbf). Static Load Rating: 7,700 N (1,730 lbf). Preload Force: 130 N (DUL). Limiting Speed: 32,100 rpm single bearing; DUL pair mounted back-to-back 25,740 rpm grease / 43,740 rpm oil. Series: MM 200 (72-series envelope). Seal Type: Open. Bore Type: Straight. Harmonization Code: 8482.10.50.68.

Dimensions and mounting:

Preload Force: 130 N as a DUL set. Assembled duplex pair width: 28 mm. Cage service temperature limit: 93°C.

Compatibility and replacement:

ISO designation: 7204E-T-P4S-DUL (E for 25°, T for the phenolic machined cage, P4S for the Fafnir MM precision spec). Schaeffler format: B7204-E-T-P4S-DUL. The 15° sibling in the same envelope, 2MM204WI CR DUL, carries a different contact angle and different ratings. Searchable variants: 3MM204WICRDUL, 3MM204WI CR DUL, 3MM-204-WI-CR-DUL, 3MM 204 WI CR DUL, 3MM204WIDUL, 3MM204WI.

Frequently asked questions:

What are the dimensions of the Fafnir 3MM204WICRDUL?

20 mm bore, 47 mm outside diameter, 14 mm width.

What is the contact angle?

25°.

What does DUL mean?

A flush-ground duplex universal pair at light preload.