RHP7018CTDUMP2Matched Duplex Pair Angular Contact Ball Bearings 90x140x24 mm 15° Medium Preload ABEC 9

Product Description

What this part is

RHP 7018-C-T-DUM-P2, a matched duplex pair of single-row angular contact ball bearings. Bore: 90 mm (3.5433 in). Outside Diameter: 140 mm (5.5118 in). Overall Width: 24 mm (0.9449 in) per bearing. Total Width: 48 mm (1.8898 in) for the mounted pair. Series: 7018, ISO dimension series 10. Rolling Elements: steel balls, one row per bearing. Closure Type: open.

Decoding the designation

Contact Angle: 15°, from the RHP angle letter C. Cage Material: laminated phenolic, from the T. Arrangement: duplex, from the DU. Preload: medium, from the M. Precision Class: P2, ABEC 9, RHP grade EP9. Base Number: 7018, bore code 18 giving a 90 mm bore.

Published specifications

Dynamic Load Rating: 71.5 kN (16,074 lbf) per bearing. Static Load Rating: 69.0 kN (15,512 lbf) per bearing. Limiting Speed: 14,600 r/min oil/air and 8,700 r/min grease for a single bearing; a medium-preload back-to-back pair runs at 0.60 of those figures. Axial Preload: 1,180 N. Axial Stiffness: 172 N/µm for the pair. Effective Load Centre: 27.4 mm. Item Weight: 5.12 lb (2.322 kg) for the pair. Maximum Operating Temperature: 120 °C. Bore Type: straight. Internal Clearance: N/A, the set is preload-adjusted.

Mounting dimensions

Shaft Abutment Diameter d1: 99 mm minimum. Housing Abutment Diameter D1: 131 mm maximum. Outer Ring Abutment Diameter D2: 134 mm maximum. Bearing Fillet Radius r: 1.5 mm minimum. Secondary Fillet Radius r1: 1.0 mm minimum. Internal Volume: 49.3 cm³ per bearing. Pitch Circle Diameter Of Lubrication Jets: 108.6 mm.

What these specs mean in practice

ABEC 9 is the tightest class in general production use, holding bore, outside diameter and running accuracy inside roughly half the P4 limits, which is what buys spindle runout in the sub-micron range. A 15° contact angle favours speed and radial stiffness over thrust capacity. As a duplex pair the set locates the shaft in both directions under a built-in medium preload of 1,180 N, giving 172 N/µm of axial stiffness. The rings are universally faced, so the pair can be stacked back-to-back, face-to-face or in tandem at the same preload value. The laminated phenolic cage is outer-ring guided and rated to 120 °C.

Quantity and configuration

Unit Quantity: 2 Pcs, one matched duplex pair. Mounting Arrangement: universally faced, DB, DF or DT.

Interchange guidance

Same-spec 15° medium-preload ABEC 9 duplex equivalents in other schemes: RHP B-series B7018X2TADUMEP9, NSK 7018CTRDUMP2, FAG B7018-C-T-P2-UM, Fafnir 2MMV9118WI-CR-DUM. The P4 grade of the same number, the light and heavy preload forms, and the 25° 7018-A5 form share the 90 x 140 x 24 mm envelope and are related sizes.