RHP7004CTDULP4Super Precision Angular Contact Ball Bearing Matched Pair 20x42x12 mm 15° ABEC 7 Light Preload

Product Description

What this part is:

A duplex-ground matched pair of RHP 7004C single-row super-precision angular contact ball bearings. Bore: 20 mm. Outside Diameter: 42 mm. Overall Width: 12 mm per bearing. Total Width: 24 mm for the pair. Contact Angle: 15°. Precision Class: P4, ISO Class 4, ABEC 7, RHP class code EP7. Precision Rating: ABEC 7. Cage Material: Laminated phenolic resin. Cage Type: Machined, outer ring guided. Closure Type: Open on both faces. Bore Type: Straight. Rolling Elements: Steel balls. Bearing Material: Carbon chrome bearing steel to BS970 534A99/535A99 or SAE 52100. Series: RHP 70, ISO dimension series 10. Number Of Rows: 1 per bearing. Design Units: Metric. Snap ring included: No.

Decoding the designation:

Type 7: single-row angular contact ball bearing. Dimension series 0: ISO series 10. Bore code 04: 20 mm bore. Contact angle C: 15°. Cage T: machined laminated phenolic resin, outer ring guided. Grouping DU: matched duplex pair, universal face control. Preload L: light. Precision grade P4: ISO Class 4, ABEC 7, RHP code EP7. Two further carton designations agree: the RHP B-series B7004X2TADULEP7, in which X2 is 15° and EP7 is ABEC 7, and the Fafnir-scheme 2MM9104WI, whose 2MM prefix is 15°.

Load ratings and speed:

Dynamic Load Rating (Cr): 11.1 kN, 11,100 N per bearing. Static Load Rating (C0r): 6.55 kN, 6,550 N per bearing. Limiting Speed: 53,600 rpm oil/air; 33,100 rpm grease, for a single bearing under spring preload with the inner ring rotating. Mounted back-to-back as a pair at light preload the figures are 42,880 rpm oil/air and 26,480 rpm grease. Lubricant: oil/air or grease. Maximum Operating Temperature: 120 °C.

What these specs mean in practice:

Contact Angle: 15°, the speed-biased angle of the two the range publishes. A 15° pair reaches a higher limiting speed than a 25° pair of the same envelope and carries less axial load and less axial stiffness.

Axial Preload, light grade, as a paired set: 49 N. Axial Stiffness, light grade, as a paired set: 28 N per micrometre. Preload removes internal play, fixes the contact angle and makes axial position and runout repeatable. The L grade adds the least friction heat of the four grades. The bearing is preload-set at manufacture rather than clearance-set.

P4 holds bore, outside diameter, width and running accuracy to single-digit micron limits. Radial runout of the assembled inner ring, Kia: 2.5 µm. Radial runout of the assembled outer ring, Kea: 5 µm. Duplex grinding converts those tolerances into the preload itself: the ring faces are relieved by a measured amount, so clamping the pair solid produces the light preload directly with no shimming.

The laminated phenolic resin cage riding on the outer ring land keeps cage inertia and ball-pocket loads low and holds an oil film well. Maximum Operating Temperature: 120 °C, set by the phenolic.

Quantity and configuration:

Unit Quantity: 2 Pcs, supplied as one matched duplex pair, duplex ground as a set. Arrangement / Configuration: matched duplex pair (DU), universal face control. Universal facing lets the pair clamp solid to the light preload back-to-back, face-to-face or in tandem. Each bearing on its own takes thrust in one direction. Back-to-back or face-to-face, the pair takes thrust in both directions; in tandem it takes a larger load in one direction only.

Mounting data:

Inner ring abutment diameter, d1 min: 25 mm. Outer ring abutment diameters: D1 max 37 mm, D2 max 39.5 mm. Fillet radii: r min 0.6 mm, r1 min 0.3 mm. Effective Load Centre (a): 10.1 mm. Internal free volume: 3.1 cm³. PCD of lubrication jets: 28.2 mm. Item weight: 0.069 kg (0.152 lb) per bearing.

Interchange guidance:

B7004X2TADULEP7 is the RHP B-series form of this envelope and angle, and 2MM9104WI is the Fafnir-scheme number for the same 15° size. NSK 7004CTRDULP4 is the current NSK-RHP catalogue designation, and FAG B7004-C-T-P4S-DUL is the Schaeffler execution. Same-envelope bearings differing in contact angle, preload grade or tolerance class — 7004A5 at 25°, the medium and heavy preload sets, and P3 or P2 class variants — are related sizes.