NTN7009CGD2GP4Super Precision Angular Contact Ball Bearing – 45 mm ID, 75 mm OD, 16 mm Width, 15° Contact Angle, ABEC 7, Universal Duplex Pair

Product Description

What this part is

An NTN 7009CGD2/GNP4 super-precision single-row angular contact ball bearing, supplied as a universally matchable duplex pair. Bore 45 mm, outside diameter 75 mm, width 16 mm per bearing and 32 mm across the mounted pair. Open on both faces, with a 15° contact angle and a glass-fibre reinforced nylon cage.

Decoding the designation

7009 is the ISO 70 dimension series at a 45 mm bore. C denotes the 15° contact angle. GD2 marks the rings as universal flush ground, so any two bearings from the family can be mounted back-to-back, face-to-face or in tandem without a spacer. GN sets the resulting preload at the normal, light step of NTN’s GL, GN, GM, GH ladder. P4 is ISO Class 4, equivalent to ABEC 7.

What these specs mean in practice

A 15° contact angle favours speed and radial stiffness over thrust capacity, which is why it is the standard machine-tool spindle angle. The glass-reinforced nylon cage runs lighter than a machined brass cage and tolerates higher speeds, with an upper service temperature of 120 °C. Limiting speed is 24,960 rpm under oil and 15,600 rpm under grease.

Load ratings

Dynamic radial load rating 39.65 kN and static radial load rating 38.60 kN, both figures applying to the mounted duplex pair rather than a single bearing. High carbon chrome steel rings and steel balls.

Quantity and configuration

Two bearings, ground as a universally matchable set. Combined weight 0.460 kg.

Fitting notes

Shaft backing shoulder da min 50.5 mm; housing backing shoulder Da max 69.5 mm and Db max 70.5 mm. Maximum chamfer for shaft and housing fillets is 1.0 mm on the outer corner and 0.6 mm on the inner. Because the set carries a factory preload, radial internal clearance does not apply.

Interchange guidance

The ISO base number is 7009C. Same-angle, same-class equivalents from other makers include the SKF 7009 CD/P4A, NSK 7009C P4 and FAG B7009C.T.P4S. A 7009A or 7009B in the same envelope carries a different contact angle and is a related size rather than an interchange.