FAGSuper Precision Spindle Bearing – 120 mm ID, 180 mm OD, 28 mm Width, Open, 15° Contact Angle, Light Preload, Phenolic Cage

Product Description

What this part is

FAG B7024CA.P4.UL super precision radial spindle bearing. Single-row angular contact ball bearing, B70 high-speed spindle series, 120 mm bore x 180 mm outside diameter x 28 mm width. Open on both faces. Carton designations: B7024CA.P4.UL, B7024C, B-7024-C-A-P4-UL, 7024-TG-P4, and the Fafnir 2MM9124.

Decoding the designation

Series: B70, Schaeffler’s high-speed spindle bearing range. Contact Angle: 15°. Cage Material: fabric-base laminate phenolic. Cage Type: machined. Precision Class: P4, equivalent to ABEC 7. Preload: light. Universally matchable, so any two rings of this designation pair into a light-preload set in back-to-back, face-to-face or tandem order.

What these specs mean in practice

A 15° contact angle favours speed and radial stiffness over thrust capacity, which is what makes the B70 range the standard choice for machine tool spindles. Radial dynamic load rating: 115,000 N. Radial static load rating: 82,000 N. Limiting speed with grease: 7,500 rpm. Limiting speed with oil: 12,000 rpm. Fatigue load limit, radial: 7,100 N. Maximum operating temperature: 100 °C. Minimum operating temperature: -30 °C. Item weight: 4.56 lb.

Stiffness and preload figures

Axial rigidity: 123 N/µm at light preload, 206 N/µm at medium, 293 N/µm at heavy. Preload force: 653 N light, 2,069 N medium, 4,129 N heavy. Lift-off force: 2,008 N light, 6,858 N medium, 14,599 N heavy. Distance between the apexes of the pressure cones: 34.1 mm.

Quantity and configuration

One bearing. Supplied as a universally matchable single ring set, ready to be combined with further pieces of the same designation.

Fitting notes

Straight cylindrical bore, interference fit on the shaft. Shaft shoulder diameter: 131 mm. Outer ring shoulder diameter: 169 mm. Maximum fillet radius: 1 mm. Minimum chamfer dimension: 2 mm. Lubrication pitch diameter range for oil injection: 138.6 mm to 145.1 mm. The phenolic cage runs to 100 °C and suits oil-air and oil-mist lubrication as well as grease.

Interchange guidance

Other makers’ 15° light-preload spindle bearings in this size: SKF 7024 CD/P4ADGB, NSK 7024CTYNSULP4, RHP 7024CTRSULP4, Timken/Fafnir 2MM9124WI-SUL, NDH Q0L24DTL7. The 25° execution of the same size is a different bearing: it carries 109,000 N dynamic and 78,000 N static with a lower speed rating.