RHPSuper-Precision Angular Contact Ball Bearing, 60 x 95 x 18 mm, ABEC 7 / P4, Phenolic Cage, Universally Ground Single, Light Preload

Product Description

What this part is

An RHP 7012 T.SUL.P4 super-precision angular contact ball bearing, 60 mm bore x 95 mm outside diameter x 18 mm wide. It is built to ABEC 7 / ISO P4 accuracy with a phenolic cage, and it is universally ground as a single with light preload. This is spindle-grade hardware, not a general-purpose bearing. Sold as 1 Pc.

Decoding the designation

7012 — single-row angular contact ball bearing, ISO 70 series, 60 mm bore. 60 x 95 x 18 mm. The 70 series is the light-section family, so a 7012 is slimmer and faster than a 7212 on the same 60 mm shaft.
T — phenolic (laminated fabric) cage. Light, self-lubricating and quiet at speed, which is why it is the standard super-precision spindle cage.
SU — single universally ground. The ring faces are ground so this piece runs correctly on its own, and any two pieces of the same designation still stack to a known preload.
L — light preload. RHP’s scale runs L light, M medium, H heavy.
P4 — ISO tolerance class 4, equivalent to ABEC 7. RHP also writes this class EP7, which is why the title carries 7012TUEP7.

SU and DU are mutually exclusive: SU means universally ground as a single, DU means ground for duplex mounting. The part number on this bearing reads SUL, so it is the single universally ground form and one piece is the intended unit of supply. Older paperwork on this listing also carried a TDU form of the number; it is kept as a search term only, because SU is what the designation says.

What these specs mean in practice

Preload is a trade-off rather than an upgrade. Preload removes internal clearance, so the spindle gains axial and radial stiffness and the balls are prevented from skidding at high speed — that is what holds a cutting tool on size. It also generates friction heat continuously, whether the machine is cutting or idling. Light preload is the high-speed choice: less heat, less stiffness. Step up to M or H only if the spindle needs the rigidity and can shed the heat. Never mix preload classes in one stack.

Universal grinding is what lets you buy one piece and fit it with confidence. On a non-universally-ground bearing you have to order a factory-matched set and keep the pieces together for life. Here the offsets are ground to a standard, so this single works on its own and will also mate correctly with another piece of the same designation if you later build a back-to-back, face-to-face or tandem stack — with no shims or ground spacers.

The phenolic cage is a speed and lubrication feature. It weighs a fraction of a brass cage, absorbs and slowly releases oil, and runs quietly, but it will not tolerate sustained high temperature or aggressive synthetic lubricants the way a steel or brass cage does. Keep it on the oil-mist, grease or oil-air lubrication it was designed for.

P4 / ABEC 7 is about running accuracy, not load. It tightens bore, outside diameter, width and runout tolerances so the spindle turns true. That accuracy is worth nothing if the housing and shaft seats are not ground to matching tolerance, so check the machine before fitting a P4 bearing to a worn spindle.

Published specifications

Bore d: 60 mm
Outside diameter D: 95 mm
Width B: 18 mm
Bearing type: single-row angular contact ball, ISO 70 series
Precision class: ISO P4 / ABEC 7 (RHP EP7)
Cage: phenolic (laminated fabric)
Grinding: universally ground as a single (SU)
Preload: light (L)
Closure: open
Sale unit: 1 Pc

Installation and setup notes

Handle super-precision bearings clean and cool: unwrap only at the machine, keep the preservative oil on until fitting unless you are flushing to a specified lubricant, and never spin a dry bearing with compressed air. Mount with a press or induction heater against the ring being fitted, never through the balls. If you are building a stack, check that every piece carries the same designation and the same preload letter, and set the orientation the spindle drawing calls for — back-to-back for moment stiffness, face-to-face for a self-aligning tendency, tandem for one-direction thrust. Both housing and shaft seats need to be ground to a tolerance that matches the bearing, or the P4 accuracy is wasted.

Interchange guidance

RHP’s bearing business became part of NSK, so the current-brand match is an NSK 7012 super-precision. MM9112WI-CR-SUL is carried on this listing as the Fafnir and Timken designation for the same 60 x 95 x 18 mm super-precision envelope with a phenolic outer-land-riding cage, universally ground as a single at light preload. Other matches with the same grinding and preload: FAG B7012-C-T-P4S-UL, NSK 7012 C or A5 TYSULP4, SKF 7012 CD/P4A, NTN 7012 T1 G GN P4. When you cross-reference a super-precision angular contact bearing, always carry across the contact angle, the grinding code and the preload letter as well as the size. Fafnir marks the angle in its prefix — 2MM is 15°, 3MM is 25° — and NSK uses C for 15°, A5 for 25° and A for 30°. A 7012 that is ground for duplex mounting, set for medium preload, or built to a different contact angle is a different part, and swapping it changes spindle stiffness and heat.