RHP7009CTDULP4Super-Precision Spindle Angular Contact Ball Bearing Duplex Pair – 45 mm Bore, 75 mm OD, 16 mm Width, 15 Degree Contact Angle, Light Preload, Phenolic Cage, ABEC 7, Open

Product Description

What this part is

An RHP super-precision spindle angular contact ball bearing, 45 mm bore, 75 mm outside diameter, 16 mm width per bearing, supplied as a duplex pair with light preload. RHP is the British line of NSK and shares its super-precision nomenclature. The 7009 designation places it in the ISO 70 light series at the 09 bore code.

Decoding the designation

Three designations on this bearing agree with each other. In 7009-C-T-DUL-P4 the C denotes a 15° contact angle in the RHP scheme, T a fabric-base laminate phenolic cage, DU a duplex pair, L light preload and P4 the precision class. In the alternative carton designation 7009X2TADUEP7 the X2 independently denotes 15° and EP7 is the same class as P4. The Fafnir equivalent 2MM9109WI carries the 2MM prefix, which is also 15°. Angle and class are therefore established from the markings alone.

What these specs mean in practice

A 15° contact angle is the high-speed, low-thrust setting. The shallow ball path minimises ball spin and gyroscopic moment, which is what allows the 23,000 rpm ceiling, and the trade is axial capacity: a 25° or 40° bearing of the same envelope carries considerably more thrust. Light preload keeps running torque and heat generation to a minimum while still eliminating internal clearance, so it suits continuous high-speed duty where thermal growth is the limiting factor. A phenolic cage piloted on the outer ring land is light, holds lubricant in the laminate and survives marginal oil films; its ceiling is temperature rather than load.

Load ratings and speed

Dynamic load rating 26.3 kN (5,910 lbf), static load rating 22.4 kN (5,030 lbf), limiting speed 23,000 rpm on oil. Operating range −30 °C to 120 °C. Running accuracy is held to the high ABEC 7 grade for both radial and axial runout.

Thrust direction and arrangement

A single-row angular contact ball bearing takes thrust in one direction only. The two bearings assembled as a duplex pair carry thrust in both directions, and the ground offset on the ring faces sets the light preload. Universal grinding means any two bearings of this designation may be arranged back-to-back, face-to-face or in tandem and will develop the specified preload when clamped.

Quantity and configuration

2 Pcs, two separate bearings forming one duplex pair. The 16 mm width is per bearing, giving 32 mm across the assembled pair. Open on both faces, no snap ring groove, straight bore.

Fitting notes

Preload develops as the ground faces are clamped together, so the shaft and housing shoulders are the datum and the clamp load must reach the ring faces squarely. The phenolic cage sets a temperature ceiling, which makes the lubrication regime and the resulting running temperature the governing constraint at the top of the speed range.

Interchange guidance

Genuine interchanges match series, angle, class and preload: SKF 7009 CD/P4ADGA, FAG B7009-C-T-P4S-DUL and Fafnir 2MM9109WI-DUL are all 15° light-preload super-precision pairs in this envelope. Same-envelope 7009 bearings at 25° (RHP E or X3, Fafnir 3MM) or 40° are related sizes rather than interchanges, as are medium and heavy preload variants of the same number.