NSKSuper Precision Angular Contact Ball Bearing 45x75x16mm 15 Degree Contact Angle ABEC 7 Moulded Polyamide Cage Open High Speed Spindle Bearing

Product Description

What this part is

An NSK 7009CTYP4 super-precision angular contact ball bearing, 45 mm bore × 75 mm outside diameter × 16 mm width. Single row, 15° contact angle, moulded polyamide cage, open, ABEC 7 precision. Carton markings also include DB and C8.

Decoding the designation

7009 – ISO base number, 45x75x16 mm boundary dimensions (the thin-section spindle envelope).

C – 15° nominal contact angle in NSK’s scheme (NSK A or A5 would be 30°).

TY – moulded polyamide (nylon) cage. NSK’s TR suffix would instead indicate a machined phenolic cage.

P4 – ABEC 7 precision class (P4S is ABEC 7/9, P5 is ABEC 5).

DB – a back-to-back duplex arrangement marking found on the carton, not part of the bearing’s own base designation.

C8 – an NSK special-specification code, reproduced here as marked.

Quantity and configuration

Sold and priced as individual bearings. The base designation as marked, 7009CTYP4, carries no SU or DU universal-grind suffix, so on the designation alone these are standard singles rather than confirmed universally ground bearings. A universally ground bearing can be clamped against any other bearing of the same designation and will self-develop the specified preload, whereas non-universal singles are matched by grinding, or run with a calculated spacer or shim stack, to achieve a predictable preload. The DB carton marking suggests supply as a back-to-back matched arrangement. Contact us before ordering if you need a confirmed preloaded duplex arrangement, so carton markings and lot numbers can be checked on the exact pieces shipped.

Why 15° and a polyamide cage

The 15° contact angle keeps the ball load path close to the radial plane. That reduces centrifugal and gyroscopic ball loading, so heat generation is lower and the practical speed ceiling is higher than a 25° or 30° bearing of the same size, and radial stiffness is better. What you trade away is thrust capacity and axial stiffness — 15° is the high-speed spindle choice, not the heavy-thrust choice. The moulded polyamide (TY) cage reinforces that character: it is very light, so cage stress at speed is low, it runs quietly, and it is forgiving of momentary lubricant starvation. Its limits are thermal and chemical — polyamide cages are generally kept well below the temperature a phenolic or steel cage will survive, and they are attacked by some synthetic lubricants and solvent cleaners. Where the machine runs hot or uses an aggressive lubricant chemistry, the TR phenolic-cage variant is the correct specification.

Why ABEC 7 is not just a quality badge

P4/ABEC 7 constrains bore, outside diameter, width and, critically, running accuracy — radial and axial runout are held to a small fraction of a commercial bearing’s allowance. That accuracy only reaches the workpiece if the shaft and housing are held to matching tolerances. An ABEC 7 bearing in a worn or out-of-round housing does not deliver ABEC 7 spindle performance.

Published ratings

Dynamic load rating 29 kN / 6519 lbf. Static load rating 24 kN / 5395 lbf. Limiting speed 18000 rpm. Temperature range -40 °C to 120 °C. Mass 0.53 lbs. Lubricant: oil.

Interchange guidance

Same-envelope 45x75x16 mm 15° candidates include NSK 7009CTRP4 (phenolic cage), NSK 7009A5TYNP4 (30°, angle differs), SKF 7009 CD/P4A, FAG B7009–C–T–P4S, NTN 7009C and GMN S6009C. Fafnir/Timken’s equivalent in the WI super-precision series is 2MM9109WI (15°). Confirm contact angle, precision class, cage material, preload class and universal-grind status before substituting.