RHP7217CTSULP4Super Precision Angular Contact Ball Bearing – Straight Bore, 85 mm ID, 150 mm OD, 28 mm Width, Open, 15° Contact Angle, Light Preload, Universal Single, ABEC 7

Product Description

What this part is

RHP 7217CTSULP4 single-row super-precision angular contact ball bearing, made in England. Bore: 85 mm. Outside Diameter: 150 mm. Overall Width: 28 mm. Contact Angle: 15°. Precision Class: P4, equivalent to ABEC 7 and to BS292 EP7. Number Of Rows: 1. Rolling Elements: Balls. Bearing Material: Carbon chrome bearing steel to BS970 534A99/535A99, equivalent to SAE 52100, through hardened. Series: 7200, ISO dimension series 02. RHP is an NSK brand.

Decoding the designation

Reading 7217-C-T-SUL-P4: 7 is a single-row angular contact ball bearing, 2 is ISO dimension series 02, the bore code 17 gives an 85 mm bore, C is the 15° contact angle, T is the laminated phenolic resin cage, SU is a single universally ground bearing, L is light preload and P4 is the precision grade. The carton also carries 7217X2TUEP7, the Fafnir cross 2MM217WI CR SUL, the short form 217HDL and B7217CTPAP4UL.

What these specs mean in practice

Dynamic Load Rating: 107.0 kN. Static Load Rating: 90.5 kN. Limiting Speed, oil-air lubrication: 14,300 rpm. Limiting Speed, grease lubrication: 8,500 rpm. Those are the single-bearing figures under light spring preload. Run as a back-to-back light-preload pair against a second SUL bearing the limiting speeds are multiplied by 0.80, giving 11,440 rpm on oil-air and 6,800 rpm on grease. Oil-air lubrication carries heat out of the bearing that grease cannot, which is why the two figures differ so widely.

Universal grinding

Arrangement: SU, single universally ground. The inner and outer rings are the same width and the faces are ground so that any two of these bearings clamped together produce the light preload value, whether they are set back-to-back or face-to-face. In tandem they share load equally. That removes the need to measure face steps or make custom-width spacers on assembly.

Cage and temperature

Cage Material: Laminated phenolic resin. Cage Type: Outer-ring guided. Maximum Operating Temperature: 120 °C, the limit set by the phenolic cage. A phenolic cage running against the outer ring land is light, damps well and tolerates marginal lubrication.

Preload and stiffness

Preload: Light. Axial Preload: 690 N for a mounted pair. Axial Stiffness: 120 N/µm. Light is the preload RHP selects most often, suiting applications where loads and speeds are not extreme. RHP publishes exactly four preload grades: extra light, light, medium and heavy.

Mounting data

Bore Type: Straight. Closure Type: Open. Minimum Shaft Abutment Diameter: 95 mm. Maximum Housing Abutment Diameter: 140 mm. Maximum Outer Ring Abutment Diameter: 144 mm. Chamfer r min: 2.5 mm. Chamfer r1 min: 1.0 mm. Effective Load Centre a: 29.7 mm. Internal Volume: 78.5 cm³. Pitch Circle Diameter Of Lubrication Jets: 109.8 mm.

Quantity and configuration

Unit Quantity: 1 Pc. Item Weight: 1.782 kg (3.93 lb). One universally ground single, which runs alone or pairs with another SUL 7217C to make up a set.

Interchange guidance

Cross-references on the same envelope, angle and preload: SKF 7217 CDGA/P4A, NSK 7217CTYNSULP4, Fafnir 2MM217WI CR SUL and 217HDL. The designation is also written 7217CTSULP4, 7217 C T SUL P4, 7217X2TUEP7 and B7217CTPAP4UL. A 7217 at a 25° contact angle shares this 85 x 150 x 28 mm envelope but carries different ratings and speeds, so it is a related size rather than a substitution.