RHPSuper Precision Angular Contact Ball Bearing Duplex Pair – 120 mm ID, 180 mm OD, 28 mm Width, 15° Contact Angle, P4, Light Preload, Open

Product Description

What this part is

RHP 7024CTDULP4 super precision angular contact ball bearings, supplied as a factory matched duplex pair. Bore: 120 mm. Outside diameter: 180 mm. Width: 28 mm per bearing, 56 mm across the pair. Series: 70, ISO dimension series 10. Single row each, open, straight bore, universally faced. Manufactured in the United Kingdom.

Decoding the designation

Contact Angle: 15°. Cage: machined laminated phenolic resin, outer ring guided. Grouping: DU, paired unit. Preload: Light. Precision Grade: P4, equivalent to EP7, ABEC 7 and ISO Class 4.

What these specs mean in practice

Dynamic Load Rating: 112 kN per bearing. Static Load Rating: 117 kN per bearing. Limiting speed: 11,200 rpm on oil/air lubrication and 7,200 rpm on grease for a single bearing. A 15° contact angle runs faster and carries less thrust than a 25°, which suits high-speed spindle duty. P4 holds tighter running accuracy, which lowers runout and vibration in a spindle: inner ring radial runout 5 µm maximum, outer ring radial runout 10 µm maximum.

Preload and stiffness

Axial preload for this light-preload pair: 830 N. Axial stiffness at light preload: 153 N/µm. Mounted back-to-back, the recommended limiting speed for a light-preload pair is 0.80 of the single-bearing figure, giving 8,960 rpm on oil/air and 5,760 rpm on grease. Preload is set at manufacture, so no internal clearance value applies.

Quantity and configuration

Two pieces, a factory matched duplex pair. Universal face control means the rings are pre-adjusted, so the pair mounts back-to-back, face-to-face or in tandem at the marked light preload without ground spacers.

Mounting data

Inner ring abutment diameter d1: 130 mm minimum. Outer ring abutment diameters D1 and D2: 170 mm and 174 mm maximum. Fillet radii r and r1: 2.5 mm and 1.0 mm minimum. Effective load centre a: 34.1 mm. Lubrication jet pitch circle diameter: 142.3 mm. Internal free volume: 93.5 cm3 per bearing. Maximum recommended operating temperature: 120 °C. Rings and balls: SAE 52100 through-hardened chrome bearing steel. Mass: 2.082 kg (4.59 lb) each, 4.164 kg (9.18 lb) for the pair.

Interchange guidance

Carton designations: 7024CTDULP4, 7024-C-T-DUL-P4, B-7024-X2-TA-UL-EP7, 2MM9124WICRDUL. Fafnir 2MM9124WI is the 15° equivalent envelope. NSK 7024CTRDULP4 is the current-scheme equivalent at 15° with the same outer-ring-guided phenolic cage. SKF 7024 CD/P4ADGA is a 15° light-preload equivalent.