SNRSuper Precision Angular Contact Ball Bearing Matched Duplex Pair, 17 x 35 x 10 mm, 15 Degree Contact Angle, Universally Ground, Light Preload

Product Description

What this part is

This is a factory-matched duplex pair of super precision angular contact ball bearings in the 7003 envelope — 17 mm bore, 35 mm outside diameter, 10 mm width per bearing. Angular contact ball bearings carry radial and one-directional axial load through a contact line inclined to the bearing axis, which is why they are almost always used in pairs or sets: two bearings opposed to each other give a spindle defined stiffness in both axial directions. Both rings are ground for universal pairing, and the pair is supplied with a preset preload built into the ring faces.

The SNR cartons are labelled MADE IN WEST GERMANY, dated 05 1992, with the full designation F20 7003 C G1 DU J74.

Decoding the designation

7003 – ISO angular contact ball bearing, 17 mm bore, 10 series envelope (35 mm outside diameter, 10 mm width).

C – in the SNR 70xx scheme, a 15° nominal contact angle.

G1 – cage and internal design code.

DU – duplex universal: ring faces ground so any two bearings from the line will mount together in any orientation with the intended preload.

J74 – the specific preload and pairing specification applied to this set.

F20 – the carton prefix printed on the SNR label, part of the full factory designation.

What these specs mean in practice

A 15° contact angle is the high-speed choice. The shallower the angle, the more of the load path is radial and the lower the centrifugal and gyroscopic penalty on the balls, so 15° bearings run faster and cooler than a 25° equivalent of the same size. The trade is axial stiffness: if your spindle is fighting heavy thrust from a drilling or hard-turning cut, a 25° bearing holds position better. For a 17 mm grinding or high-frequency spindle, 15° is normally the correct answer.

Universally ground rings matter because they remove a decision from the fitter. A DU bearing can be set back-to-back for maximum moment stiffness, face-to-face for tolerance of shaft and housing misalignment, or in tandem to double axial capacity in one direction — all with the same parts and the same resulting preload.

Mounting data

Boundary dimensions are ISO-standardised: 17 mm bore, 35 mm outside diameter, 10 mm width per bearing. Precision class P4 / ABEC 7. Preload class light, factory preset to the J74 pairing specification.

Set composition

One lot equals one matched pair equals two physical bearings. Two individually wrapped bearings in two SNR cartons, both labelled with the same designation. The pair should be kept together and mounted together; a matched set separated across two machines loses the preload it was ground for.

Interchange guidance

The equivalent common-designation forms are 7003-C-T-DUL-P4, 7003CDUL, 7003 C DU and 7003CG1DUJ74. The obsolescence trail is SNR to NTN-SNR. Cross-brand equivalents in the same envelope and angle class include the Timken/Fafnir 2MM9103WI series, NSK 7003C, and FAG/Schaeffler B7003-C-T-P4S families, but preload class and cage material vary between them, so confirm the suffix on any substitution rather than matching only the base number.