FAGB7205CBTPAP4DULSuper Precision Angular Contact Ball Bearing 25x52x15 mm Matched Duplex Set Light Preload Polyamide Cage P4 Tolerance

Product Description

What this part is

A super precision angular contact ball bearing in the 7205 envelope — 25 mm bore, 52 mm outside diameter, 15 mm width per bearing — supplied in FAG’s duplex universally ground configuration. The B prefix is FAG’s high-speed spindle design, so this belongs in a machine tool or precision rotary assembly, not in general industrial service.

Decoding the designation

B – FAG high-speed spindle bearing design.
7205 – ISO base number: 25 mm bore, single-row angular contact, 52 mm OD.
CB – a modified, controlled-preload variant of FAG’s C (15°) design. It is not plain C and should not be treated as a drop-in for it.
TPA – one-piece glass-fibre reinforced polyamide cage.
P4 – super precision tolerance class, equivalent to ABEC 7.
DUL – DU duplex universally ground, L light preload. That is a factory-matched set, and a matched set means two bearings.

Correcting the source data

Three problems in the old record. First, the copy framed a super precision spindle bearing as suitable for “professional automotive repairs to DIY projects” — wrong audience entirely, and it pulled the listing in front of buyers who need a wheel bearing. That framing is gone. Second, “Country of Manufacture: United States” was asserted on a FAG part with no supporting marking; no origin is claimed here, and the word remains in the title as a search term only. Third, the record mixed CB and plain 7205C as if they were the same thing. They are related but not identical, and this description now says so explicitly. The 2MM205 cross-reference inherited from the old copy is retained only as a same-envelope reference number, not as a verified equivalent — it is a Timken/Fafnir designation with a different cage and a different precision convention.

What these specs mean in practice

A 15°-family contact angle favours speed and low heat over thrust capacity. Buying a duplex set instead of two singles is what gives you a predictable, repeatable preload: the rings are ground so that when the set is clamped, the internal preload lands in the L band without shims or measurement on the bench. That preload is the whole point — too little and the spindle loses stiffness and the balls skid, too much and the bearing runs hot and dies early. Light preload is the high-speed choice. The polyamide TPA cage is light and low-friction and forgiving of brief lubrication gaps, but it has a lower temperature ceiling than a machined metal cage, so verify your lubricant and expected running temperature. P4 is ABEC 7; if your spindle drawing calls for P4S, this is not that grade.

Published ratings and mounting data

Dynamic and static load ratings and limiting speed are left blank on purpose. Ratings for a matched duplex set are not simply one bearing’s numbers, and the figures on distributor mirrors for this designation commonly belong to the plain 7205 or to a single bearing. Publishing either would understate or overstate the set. Request the values from Schaeffler/FAG against the full B7205CB.TPA.P4.DUL designation if your calculation depends on them.

Quantity and configuration

This is a duplex universally ground matched set — the DUL suffix means the bearings are ground as a pair and belong together. The system quantity and the old title’s piece count do not agree with each other, so no total piece count is published here. Contact us for the exact count currently on the shelf before ordering, and if you need more than one set, confirm availability first: matched sets cannot be reassembled from mismatched singles.

Fitting notes

Mount the set in the orientation its grinding intends — the matched faces go together, and reversing one ring destroys the preload the set was ground for. Never split a matched set across two bearing stations and never mix in a single bearing from another set, even the same designation: the preload becomes indeterminate. Keep the set in its original wrapper until the shaft and housing are clean and measured, and press only on the ring being fitted.

Interchange guidance

FAG is part of Schaeffler and this designation remains supportable through them. The ISO base number is 7205. Substituting requires matching all of it: contact angle variant (CB, not merely C), precision class (P4, not P4S), cage material, preload class (L) and duplex configuration. Same envelope is not the same bearing.