SNFAVEX25-7CE1DUHigh-Speed Super Precision Angular Contact Ball Bearing 25 x 47 x 12 mm, 15° Contact Angle, ABEC 7 Class, Universally Ground for Duplex Mounting — Single Bearing (Half of a Pair)

Product Description

What this part is

A super precision angular contact ball bearing from SNFA’s VEX high-speed spindle range, in the 7005 envelope — 25 mm bore, 47 mm outside diameter, 12 mm width. The VEX series is SNFA’s high-speed execution: thin section, shallow contact angle, and ground for duplex mounting.

Decoding the designation

VEX — SNFA high-speed super precision angular contact spindle bearing series.
25 — bore diameter, 25 mm. The envelope is 25 x 47 x 12 mm, matching ISO 7005.
7 — ABEC 7 precision class. In this SNFA scheme the digit ahead of CE is the tolerance grade, so a VEX25-9CE1 would be the ABEC 9 version of the same bearing.
CE1 — the trailing 1 is the contact angle code: 15°.
DU — duplex, universally ground. The ring faces are ground so that any two bearings of this designation clamp up to a known preload with no shims.
-1/2PR — half of a pair. See the note below; this is the most important element in the whole number.

Quantity and configuration

One bearing ships, not two. The -1/2PR suffix literally means half of a pair — SNFA’s way of ordering a single bearing out of a duplex-ground designation. That is exactly what you want if you have damaged one bearing of an existing VEX25 pair and need to replace just that half, or if you are building a triplex or quad stack and need an odd count. If you need a complete pair for a fresh build, order two.

Because the bearing is universally ground (DU), it will combine with any other bearing of the same designation: back to back (DB) for maximum moment stiffness and thrust in both directions, face to face (DF) where housing alignment is imperfect, or in tandem (DT) to double one-direction thrust capacity.

What these specs mean in practice

The 15° contact angle is the speed choice. A shallow angle keeps the ball from climbing the raceway shoulder, which cuts ball spin, friction and heat generation, so the bearing tolerates far higher rpm than a 25° or 30° bearing of the same size. What you trade away is thrust capacity and axial stiffness. On a small high-speed spindle — a grinding wheel head, a router or drilling spindle, a small turning spindle — that is the right trade, because the loads are modest and the speed is the whole point.

ABEC 7 running accuracy at 25 mm bore means the bearing itself will hold runout to a few microns. Whether the spindle does depends entirely on the seats it is mounted in.

Fitting notes

Small super precision bearings are easy to ruin during assembly. Hold shaft journal and housing bore runout and roundness to a few microns, keep the abutment faces square, and mount with a proper press or arbor that loads only the ring being fitted — on a 12 mm wide bearing it takes very little carelessness to drive force through the balls and brinell the raceways. Keep the marked face oriented as intended when you build it into a set; reversing a bearing changes the preload. Lubricate with a spindle grease or oil mist rated for the intended speed, and keep the fill light.

Interchange guidance

SNFA is a French maker, and its super precision range is now part of SKF — a useful trail to know, because current literature for these bearings appears under the SKF name. Same-envelope 15° equivalents include SKF 7005 CD/P4A, FAG B7005-C-T-P4S-UL, NSK 7005C, RHP 7005-C-T-SUL-P4, NTN 7005C and Fafnir/Timken 2MM9105WI (the Fafnir 2MM prefix is 15°, so it is a true contact angle match). The 7005-C designation carried on this listing is consistent: C denotes 15° in FAG and NSK nomenclature, which matches the SNFA CE1 code. Bear in mind that all of those cross-references are ordinarily supplied as complete single bearings or full pairs; only the SNFA number carries the half-of-a-pair convention.