RHP7211CTDUHP4Super Precision Angular Contact Ball Bearing – Straight Bore, 55 mm ID, 100 mm OD, 21 mm Width, Open, 15° Contact Angle, Universally Matchable Pair, Heavy Preload

Product Description

What this part is: An RHP 7211CTDUHP4 super-precision single-row angular contact ball bearing, supplied as a matched pair. Bore 55 mm, outside diameter 100 mm, width 21 mm per bearing. Straight bore, open on both faces, 15° contact angle, phenolic cage. RHP is now part of NSK. Decoding the designation: 7211 is the ISO 72 dimension series at a 55 mm bore. C is the RHP and NSK code for a 15° contact angle, where E would indicate 25° and no angle letter at all would mean 40°. T marks the phenolic cage. DU denotes universally matchable rings, and the H that follows sets the preload at the heavy step. P4 is ABEC 7. Cross-confirmed designations: The carton also carries B7211X2TADUHEP7 and the Timken Fafnir number 2MM211WI-CR-DUH. In the RHP B-series scheme X2 means 15° and EP7 means ABEC 7; in the Fafnir scheme the 2MM prefix likewise means 15°. All three numbering systems agree on the angle and the precision class. What these specs mean in practice: A 15° contact angle favours speed and radial rigidity over thrust capacity. Heavy preload raises spindle stiffness and running accuracy at the cost of higher operating temperature and a lower speed ceiling, which is why it suits heavy-cut milling and boring spindles rather than high-rpm grinding. The phenolic cage is light, self-lubricating and tolerant of momentary lubricant starvation, with a service range of -30 °C to 120 °C. Load ratings: Basic dynamic radial load rating 49.0 kN and basic static radial load rating 38.0 kN, each per bearing. Limiting speed 16,000 rpm. Weight 1.35 lb. Quantity and configuration: Two bearings, universally ground as a matched heavy-preload set. Because the preload is set at manufacture, radial internal clearance does not apply. Supplied without a snap ring. Cross-reference guidance: The ISO base number is 7211C. The Fafnir 2MM211WI-CR-DUH has the same angle and preload. The SKF 7211 CD/P4ADGC has the same angle at medium preload rather than heavy. A 7211E, 7211A or 7211B in the same envelope carries a different contact angle, and a DUL or DUM version carries a lighter preload; both are related sizes only.