NDHQ0L12DTT7ASuper Precision Angular Contact Ball Bearing Matched Tandem Pair DT 60x95x18mm 15 Degree ABEC 7 Phenolic Cage

Product Description

What this part is

A matched tandem pair of New Departure Hyatt Q-series super-precision angular contact ball bearings on the 7012 envelope: 60 mm bore, 95 mm OD, 18 mm wide each, 36 mm stacked. Phenolic cages and ABEC 7 accuracy put these in machine tool spindles, grinding heads and precision ball screw ends where a heavy one-way thrust has to be carried at speed.

Decoding the designation

Q — NDH precision angular contact ball bearing line0L12 — NDH size and design code; bore code 12 is the 60 mm bore, 7012 envelopeDT — duplex tandem, a factory-matched pair mounted facing the same directionT — phenolic cage7A — NDH variant suffix from the carton; kept as a search term rather than published as a spec, as NDH’s definition is not published
The carton cross-references 7012C-T-P4 and Fafnir 2MM9112WI-CR, which agree on 15° contact angle, phenolic cage and P4 / ABEC 7 class.

What these specs mean in practice

Tandem is a deliberate choice, not a variation on back-to-back. Both bearings face the same way so their thrust capacities add — roughly double a single bearing — but in one direction only, which means the shaft still needs something else to locate it the other way. Mounting a tandem set back-to-back instead would give two-way location while throwing away the doubled one-way capacity and the intended load sharing. The 15° contact angle keeps the speed ceiling high, and the phenolic cage is light and quiet at speed but must be kept away from solvents and steam. ABEC 7 accuracy only reaches the work if the shaft and housing seats are ground to a matching class.

Published specifications

Bore: 60 mmOutside diameter: 95 mmWidth: 18 mm each bearingTotal width mounted as a tandem pair: 36 mmContact angle: 15°Tolerance class: P4 / ABEC 7Cage: phenolicArrangement: duplex tandem (DT)Rows: single row eachClosure: open

Quantity and configuration

Two bearings, supplied as the factory-matched tandem set. Mount both facing the same direction with the high shoulders taking the thrust. Do not split the pair or mix in a bearing from another set — even load sharing depends on the matched grind.

Fitting notes

Identify the high-shoulder face of each outer ring before pressing, and mark the faces so the arrangement can be reproduced at the next rebuild. Clamp the pair as a unit; an unclamped ring puts the whole thrust load on one bearing. Mount clean, press only on the ring being fitted, and lubricate sparingly — overfilling a phenolic-caged precision pair is the usual cause of early heat failure.

Interchange guidance

Same-specification alternatives are 7012-envelope 15° ABEC 7 phenolic-cage bearings supplied as a matched tandem pair, including 7012C-T-P4 tandem sets and the Fafnir 2MM9112WI-CR in a tandem arrangement. Related but NOT interchangeable: DB or DF pairs of the same size, 7012A5 (25°) or 7012A (30°), and any single bearing of this number on its own.