SNRSuper Precision Angular Contact Ball Bearing – Straight Bore, 105 mm ID, 160 mm OD, 26 mm Width, Open, 15° Contact Angle.

Product Description

What this part is

SNR 7021CG1DUJ74 single-row super-precision angular contact ball bearing. Brand: SNR. Manufacturer Part Number: 7021CG1DUJ74. Bore: 105 mm. Outside Diameter: 160 mm. Width: 26 mm. Series: 7000. Number of Rows: 1. Rolling Elements: Ball. Bearing Material: bearing steel. Closure Type: open on both faces. Bore Type: straight. Item Weight: 3.44 lbs.

Decoding the designation

Contact Angle: 15°. Preload: light. Precision Class: ABEC 7, the P4 class. Cage Material: phenolic laminate. Cage Type: outer-ring centred. Mounting Arrangement: universally ground. Lubricant: oil or grease. Minimum Temperature: -30°C. Maximum Temperature: 120°C.

The carton carries this bearing in four schemes: SNR 7021 C G1 DU J74, FAG 7021-C-T-DUL-P4, Fafnir 2MM9121WI CR DUL and SKF 7021 CD/P4ADGA. Searchable variants of the number include 7021CG1DUJ74, 7021 C G1 DU J74, 7021-C-G1-J74 and 7021C.

What these specs mean in practice

A 15° contact angle keeps the load path close to the radial plane, favouring speed and radial stiffness over thrust capacity. That is the trade a large high-speed spindle position normally wants.

Dynamic Load Rating: 90.4 kN. Static Load Rating: 93.0 kN. At this size the static figure sits above the dynamic one, which is normal for the 70-series from bore code 20 upward: the static rating is governed by permanent raceway deformation under a standing load, and it climbs faster with size than the fatigue-governed dynamic rating does.

The laminated phenolic cage is light and absorbs oil, so it runs cooler and quieter than brass or steel at high shaft speed, and the 120°C ceiling reflects the phenolic. Centring the cage on the outer ring lets the stationary ring govern cage position, which steadies cage motion through acceleration and deceleration. ABEC 7 precision holds low radial and axial runout and gives close, repeatable shaft location. Light preload removes internal play and fixes the ball path, which is why this bearing is set by preload rather than by an internal clearance class.

Quantity and configuration

Unit Quantity: 1 Pc. The -1/2PR marking denotes one bearing from a universally ground pair, so it can be set against a matching bearing in any face orientation and will arrive at the designed light preload.

Interchange guidance

Closest matches: FAG B7021-C-T-P4S-DUL and Fafnir 2MM9121WI CR DUL, both 15° light-preload universal duplex parts. Near part: SKF 7021 CD/P4ADGA, whose DGA suffix is SKF’s extra light preload. Harmonization Code: 8482.10.50. A 7021 built at 25° is a related size rather than a substitution, because the steeper angle changes both the thrust capacity and the speed behaviour. A medium or heavy preload execution of the same number is likewise a related build, not a match.