RHP7013ETDUMP4Matched Pair Super Precision Angular Contact Ball Bearings 65x100x18 mm, 25° Contact Angle, Phenolic Cage, ABEC 7, Medium Preload, Universally Ground Duplex Set

Product Description

Part identity

RHP (now NSK) 7013ETDUMP4 super precision angular contact ball bearings, supplied as a universally ground duplex matched pair. Brand: RHP. Designation: 7013ETDUMP4. Base number: 7013E. Series: 70 (ISO dimension series 10, light section). Bore code: 13. Contact angle: 25°. Precision class: P4 (ISO class 4, ABEC 7, RHP EP7). Preload: medium (M). Grouping: DU, duplex universal. Closure: open. Rows: one per bearing, two in the mounted set. Rolling elements: balls. Harmonization code: 8482.10.50. Unit quantity: 2 bearings, one matched duplex pair.

Dimensions

Bore d: 65 mm. Outside diameter D: 100 mm. Width B: 18 mm per bearing. Ring chamfer r min: 1.1 mm. Second chamfer r1 min: 0.6 mm. Design units: metric. Mass: 0.435 kg per bearing, 0.870 kg (1.92 lb) for the two-piece set. Bearing material: through-hardened high carbon chromium bearing steel to BS970 534A99 / 535A99, equivalent to SAE 52100.

Load ratings and speeds

Per bearing, basic dynamic load rating Cr: 35 000 N (35.0 kN). Basic static load rating C0r: 32 500 N (32.5 kN). Limiting speed with oil/air lubrication: 18 400 rev/min. Limiting speed with grease lubrication: 11 400 rev/min. Both speed figures are single-bearing values under spring preload with the inner ring rotating; the corresponding figure for a back-to-back medium-preload pair is 0.60 of them, a face-to-face pair is reduced by a further 50 per cent, and a spring-loaded tandem pair carries a factor of 0.95.

Preload and stiffness

Axial preload for a medium-preload pair in the 70-series 25° range at bore code 13: 880 N. Axial stiffness for the same pair: 272 N/µm. For comparison within the same range, the light grade is 390 N and 196 N/µm, and the heavy grade is 1 770 N and 356 N/µm.

Mounting data

Effective load centre a: 28.2 mm per bearing. Abutment diameters: d1 min 72 mm, D1 max 93 mm, D2 max 95 mm. Internal free volume: 19.0 cm³ per bearing. Pitch circle diameter for lubrication jets dT: 77.5 mm. Maximum recommended operating temperature for a laminated phenolic resin cage: 120 °C. Recommended shaft fit at P4 in this diameter range: +3 to −2 µm, a mean 3T interference. Recommended housing fit at P4 for a locating position: +5 to −2.5 µm, a mean 5C clearance.

Designation breakdown

7 is a single-row angular contact ball bearing. 0 is RHP dimension series 10, the ISO 70 light section. 13 is the bore code for 65 mm. E is the 25° contact angle in the RHP scheme, corresponding to A5 in NSK’s. T is the outer-ring guided laminated phenolic cage, written TR in full. DU is duplex universal grouping. M is medium preload. P4 is precision grade 4.

Cage and contact angle

Cage type: machined one-piece, outer-ring guided. Cage material: laminated phenolic resin. The material and design suit high rotational speed and quiet running, and the cage’s own porosity retains lubricant. A 25° contact angle places more of each ball’s contact load along the shaft axis than the 15° C angle in the same envelope, giving higher axial load capacity and greater axial stiffness at a lower limiting speed — the 15° 7013C runs to 21 600 rev/min on oil/air against 18 400 for this bearing, at Cr 37 000 N and C0r 34 500 N.

Universal face control and arrangement

The inner and outer rings are the same width and the relative positions of the faces on both sides of each bearing are adjusted at manufacture so that a predetermined preload force exists once the pair is clamped together. The set therefore mounts back-to-back or face-to-face at the same preload value with no shims and no ground spacers, and shares load equally in tandem. Back-to-back (DB) mounting produces the highest radial and moment stiffness; face-to-face (DF) accommodates shaft-to-housing misalignment; tandem (DT) shares thrust in one direction between the two bearings. The high point of radial runout is marked by a small circle or burnished spot on the inner ring face, and a V line on the outer ring outside diameter marks the direction of the contact angle.

Applications

Machine tool spindles, milling and turning centres, grinding heads, precision gearboxes, rotary and indexing tables, high-thrust precision shafts, and test rigs.

Interchange

NSK equivalent designation: 7013A5TRDUM P4. Same-envelope designations elsewhere: SKF 7013 ACD/P4ADGB (SKF AC = 25°, DGB = back-to-back matched set), FAG B7013-E-T-P4S-UM. Search forms carried on this record: 7013E-T-DUM-P4, 7013 E T DUM P4, 7013E, 7013. The 15° 7013C bearing shares the 65x100x18 mm envelope with a different contact angle, load rating and speed capability.