RHPHybrid Ceramic Super Precision Angular Contact Ball Bearing 65x100x18 mm, Silicon Nitride Balls, 15° Contact Angle, P3 Accuracy, Machined Phenolic Cage, Universal Duplex Light Preload — Matched Pair

Product Description

What this part is

Two single-row hybrid ceramic super-precision angular contact ball bearings, together one complete matched duplex pair. Bore: 65 mm. Outside Diameter: 100 mm. Overall Width: 18 mm. Contact Angle: 15°. Cage Material: laminated phenolic resin. Cage Type: machined, outer-ring guided. Precision Class: RHP P3. Preload: light. Rolling Elements: silicon nitride ceramic balls. Bearing Material: through-hardened carbon chrome bearing steel rings, SAE 52100. Series: 70xx, ISO dimension series 10. Number Of Rows: 1 per bearing. Closure Type: open. Unit Quantity: 2 Pcs. This is a high-frequency spindle bearing, fitted to grinding spindles, high-speed milling heads and motorised spindles where the limiting factor is heat and centrifugal ball load. The bearing is preload-set at manufacture rather than clearance-set.

Decoding the designation

7013SCTDULP3. 7013: single-row angular contact ball bearing, ISO dimension series 10, bore code 13, boundary dimensions 65 × 100 × 18 mm. S: ceramic ball construction. C: 15° contact angle. T: machined laminated phenolic cage. DU: duplex universal, universally ground faces, mountable back-to-back, face-to-face or in tandem at the catalogue preload with no spacers. L: light preload. P3: RHP intermediate accuracy grade.

Precision grade P3

Precision Class: RHP P3 — ISO 492 Class 4 external tolerances combined with ISO 492 Class 2 running accuracy. That gives the bore and outside-diameter tolerances of a Class 4 bearing with the runout of a Class 2 one, so P3 fits shafts and housings machined for a Class 4 bearing while running as true as a Class 2. Inner-ring assembled radial runout Kia at 65 mm bore: 1.3 µm band per the P3 column for reference-face runout, with Kia 2.5 µm. Outer-ring assembled radial runout Kea at 100 mm outside diameter: 5 µm.

Ceramic ball construction

Silicon nitride balls weigh roughly 40 % of a steel ball of the same diameter. Lower ball mass means lower centrifugal load at speed, so the contact angle stays closer to its design value as the spindle winds up, which lowers contact stress and heat and raises usable speed. The balls are harder than the rings and have a lower coefficient of friction against steel, so a hybrid bearing runs cooler on the same lubricant. Ceramic is electrically insulating, which makes hybrid bearings the standard answer to shaft-current damage on motorised and inverter-driven spindles.

Silicon nitride has a higher elastic modulus than steel, so the contact patch is smaller and contact stiffness is higher. A hybrid pair suits speed, heat and electrical isolation as the constraint. A steel pair suits static and dynamic load as the constraint.

Published geometry and mounting data

From the RHP super-precision catalogue, Table 9, ISO series 10, row 7013. Bore d: 65 mm. Outside Diameter D: 100 mm. Width B: 18 mm. Chamfer r min: 1.1 mm. Chamfer r1 min: 0.6 mm. Shaft Abutment Diameter d1 min: 72 mm. Housing Abutment Diameter D1 max: 93 mm. Housing Abutment Diameter D2 max: 95 mm. Effective Load Centre a: 20.0 mm. Internal Free Volume: 19.0 cm³. Lubrication Jet Pitch Circle Diameter dT: 77.5 mm. Item Weight: 0.435 kg per bearing, 0.870 kg per pair. Axial Preload, light class, 15°, bore code 13: 250 N per pair, with EL 125 N, M 540 N and H 1,080 N. Axial Stiffness, light class, 15°: 82 N/µm.

Quantity and configuration

Unit Quantity: 2 Pcs — one complete matched duplex pair, supplied with both original RHP cartons marked 7013SCTDULP3. Arrangement / Configuration: duplex universal (DU), mountable back-to-back (DB), face-to-face (DF) or tandem (DT). The preload was established across these two specific bearings, and universal facing sets the arrangement choice at assembly.

Mounting data

Universal facing sets the preload at manufacture: the same catalogue preload back-to-back or face-to-face, and equal load sharing in tandem. Shaft Abutment Diameter d1 min: 72 mm. Housing Abutment Diameter D1 max: 93 mm. Housing Abutment Diameter D2 max: 95 mm. Chamfer r min: 1.1 mm. Chamfer r1 min: 0.6 mm. Effective Load Centre a: 20.0 mm. Internal Free Volume: 19.0 cm³. Lubrication Jet Pitch Circle Diameter dT: 77.5 mm. Catalogue limiting-speed factors for a back-to-back pair: EL 0.85, L 0.80, M 0.60, H 0.40; a face-to-face pair takes a further 50 % reduction; a spring-loaded tandem pair takes a 0.95 factor. The ceramic balls give electrical isolation across the bearing.

Interchange guidance

SKF 7013 CD/HCP4A DBA is a same-envelope equivalent: CD is SKF’s 15° high-capacity design, HC is SKF’s hybrid ceramic suffix, P4A is SKF’s class-4-dimensional grade with tighter runout, and DBA is a matched back-to-back pair at light preload. Contact angle, ball material and preload all match this RHP pair. SKF’s DBA is a fixed back-to-back pair, where RHP’s DUL is universally faced and also mounts face-to-face or tandem. The modern NSK reading of this designation is 7013C TR DUL P3 in ceramic-ball construction. RHP became part of NSK when NSK acquired the RHP group in the early 1990s, the business traded as NSK-RHP until the name reverted to plain NSK in November 2000, and these bearings are still made at the former Ransome & Marles works in Newark, England. Other same-envelope hybrid options are FAG HCB7013-C-T-P4S and NTN 7013 HX series.

Carton and ring markings

Carton: 7013SCTDULP3, RR, NB5U5, D:T, d:T, 6G-08, MADE IN ENGLAND. Ring engraving: 7013SCTDULP3, RHP ENGLAND, 2C.