GMNSuper Precision Angular Contact Spindle Bearing 45x75x16mm 15 Degree Contact Angle ABEC 7 Phenolic Cage Universally Ground Light Preload – ONE Bearing

Product Description

What this part is

One GMN S6009CTAA7DUL super-precision spindle bearing, 45 mm bore × 75 mm outside diameter × 16 mm width. Single row angular contact, 15° contact angle, phenolic (textile-laminate) cage, open, ABEC 7 precision, universally ground for light-preload duplex pairing. Made in Germany, new old stock.

You are buying ONE bearing

The DUL suffix stands for duplex, universally ground, light preload. It describes how two of these bearings behave when they are clamped together — it is a grind and preload specification, not a pack quantity. Quantity supplied here is one (1) bearing. A matched duplex pair requires two units.

Decoding the designation

S – GMN’s spindle bearing series prefix.

6009 – GMN’s series numbering for the 45x75x16 mm envelope; the equivalent ISO angular contact base number is 7009.

C – 15° nominal contact angle.

TA – phenolic / textile-laminate cage.

A7 – ABEC 7 precision class.

DUL – duplex, universally ground, light preload.

Why universally ground rings can be paired in any orientation:
Universal grinding relieves the ring faces by a controlled, symmetrical amount. Any two bearings of this designation can therefore be stacked back-to-back, face-to-face or in tandem, in either orientation, and clamping the rings solid produces the specified light preload — no calculated spacer, no shim stack, no measuring. That flexibility is the entire commercial reason universal grinding exists, and it is why this single bearing remains useful: it can still be paired later with another unit of the same designation. A non-universal single cannot.

Why the preload class must match

Light preload is a deliberate design point, not an entry-level grade. It gives lower heat generation and a higher speed ceiling at the cost of axial and radial stiffness; medium and heavy preload reverse that trade. A light-preload bearing paired against a medium-preload unit yields a preload that matches neither specification and cannot be predicted from either data sheet.

Why 15° rather than 25°

A 15° contact angle keeps the ball load path near the radial plane, which limits centrifugal and gyroscopic ball loading and therefore keeps the bearing cooler and faster than a 25° or 30° bearing in the same envelope, with better radial stiffness. The price is thrust capacity. The preload a given clamp-up develops changes with contact angle, and so does the heat the assembly generates.

Published ratings

Dynamic load rating 24.5 kN. Static load rating 19.3 kN. Limiting speed 18000 rpm. Temperature range -30 °C to 120 °C. Mass 0.53 lbs.

Mounting data

Boundary dimensions 45 x 75 x 16 mm, straight bore. Practical temperature ceiling for the phenolic cage is in the region of 120 °C.

Condition

New old stock in opened packaging, made in Germany. The original grease has dried in storage, so the bearing may not spin freely as received and should be cleaned and relubricated to the machine’s lubrication specification before fitting. Phenolic cages are damaged by aggressive solvents; clean with a compatible bearing solvent only.

Interchange guidance

Same-envelope 45x75x16 mm 15° super-precision candidates include NSK 7009CTRP4 and 7009CTYP4, SKF 7009 CD/P4A, FAG B7009–C–T–P4S, NTN 7009C, and Fafnir/Timken 2MM9109WI (15°, WI super-precision series; Fafnir → Timken is that brand’s obsolescence trail). Confirm contact angle, precision class, cage material, preload class and universal-grind status before substituting; the envelope alone is not an interchange.