NDHQ20215Angular Contact Ball Bearing 75 x 130 x 25 mm, 15 Degree Contact Angle, Quiet Grade, Open, 1 Pc

Product Description

What this part is

A single New Departure Hyatt angular contact ball bearing in the 7215 envelope — 75 mm bore, 130 mm outside diameter, 25 mm width. Open, 15° contact angle, quiet-running selection. New old stock American product, for spindles, pump and gearbox shafts and precision rotary positions carrying combined radial and one-direction thrust load on a large bore.

Decoding the designation

20215 — NDH’s number for the ISO 7215 size, 75 x 130 x 25 mm. The 20-series prefix is the 15° angular contact family; the 30-series is the steeper 40° build.
Q — NDH quiet-running selected series, screened for low noise and vibration.
No DT or DU suffix follows, so this is a single bearing rather than part of a ground tandem or duplex set.

What these specs mean in practice

A 15° contact angle keeps the ball load close to radial. That cuts centrifugal ball loading and the heat it generates, so the bearing runs faster and cooler than a 40° build in the same envelope — and carries appreciably less thrust with less axial stiffness. On a 75 mm bore that choice is deliberate: this is an accuracy-and-speed bearing rather than a heavy-thrust one, which is why it turns up on machine spindles and precision shafting rather than on screw jacks. The Q quiet-running selection screens rings and balls for low noise and low transmitted vibration, and matters wherever the bearing sits near an operator, a measuring head or a finish-critical cut. Because a 15° bearing carries only modest thrust on its own, sizing matters: if the axial load is high, the usual answers are a tandem pair or a steeper contact angle, not a bigger 15° bearing.

Quantity and configuration

1 Pc — one bearing. It is not part of a matched set, so if the assembly needs a ground preloaded pair, specify a DT or DU set rather than combining two singles.

Fitting notes

Angular contact bearings take thrust in one direction only, so the assembly must oppose it — a second bearing, a spring pack or a shoulder. Orientation matters: the wide land of the outer ring faces the thrust load, and a bearing fitted backwards loads a shoulder never designed to take it. Interference fit adds internal preload, so check shaft and housing sizes against the drawing before fitting. Induction-heat rather than hammer a 75 mm bore onto a tight shaft, never press through the ball complement, and remember that a quiet-grade bearing is only as quiet as the housing it sits in — a distorted bore undoes the selection.

Interchange guidance

New Departure Hyatt was General Motors’ bearing division and the brand is long out of production, so cross-reference by the ISO number: 7215 at 15°. Genuine same-angle equivalents in this envelope include SKF 7215 CD/P4A, FAG B7215-C-T-P4S, NSK 7215C and Fafnir/Timken 2MM9115WI. Related sizes fill the identical 75 x 130 x 25 mm envelope at other contact angles — 7215AC and 7215 ACD are 25°, 7215B and 7215 BEP are 40°, and NDH’s own 30215 is the 40° version of this number. Those are different parts with different thrust capacity and speed ratings, not substitutes, but worth knowing if your drawing calls for a steeper angle.