NSK7020CTRDULP4YSuper-Precision Angular Contact Ball Bearing – 100 mm ID, 150 mm OD, 24 mm Width, Open, 15° Contact Angle, P4Y, Universally Ground Light Preload, Phenolic Cage

Product Description

What this part is

An NSK 7020CTRSULP4Y super-precision angular contact ball bearing in the 100 x 150 x 24 mm envelope, ISO base number 7020. Single row, 15° contact angle, universally ground for light preload, with an outer-ring-guided phenolic cage and the P4Y precision class.

Decoding the designation

7020 is the ISO 70 light series at 100 mm bore. C is NSK’s 15° contact angle code, distinct from A5 at 25° and A at 30°. TR is a machined phenolic cage guided on the outer ring land, rated for continuous operation to 120 °C; NSK’s polyamide cage carries the separate code TYN. SU is a single universally ground bearing and L is light preload. P4Y is an NSK special precision class held tighter than P4.

What these specs mean in practice

The bearing carries radial load and axial load in one direction, so two or more are stacked to locate a spindle in both directions. The 15° angle is the high-speed setting: less thrust capacity than a 25° bearing on the same envelope, but a higher speed ceiling and less heat generated. A phenolic cage guided on the outer ring land runs against a film of oil on the guiding surface, which makes it stable at high speed and quiet, and the fabric-laminate body holds oil. Its 120 °C ceiling is higher than a polyamide cage will take. Light preload removes internal play without loading the ball complement hard, keeping friction torque and running temperature low. Basic dynamic load rating is 80.5 kN and basic static load rating 80.0 kN. P4Y holds bore, outside diameter and raceway runout tighter than the standard P4 class.

Quantity and configuration

Sale unit is one piece. SU marks the bearing as a single universally ground unit, so any two bearings from this range come up to the specified light preload when clamped solidly, in a back-to-back, face-to-face or tandem stack, and this bearing also runs on its own. The carton and listing also carry the DUL duplex form of the number as a searchable designation; the SU reading is the one that describes what this part is.

Fitting notes

The inner ring seats on a ground shaft with a light interference fit and the outer ring takes a close fit in the housing, each clamped against a face square to the axis. Preload is realised only once the rings are drawn solidly against their shoulders. A phenolic cage suits oil, oil-air and grease lubrication; oil-air gives the highest speed on this class.

Interchange guidance

Same-specification equivalents on this envelope at 15°, super-precision, universally ground light preload include SKF 7020 CD/P4A with light preload, FAG B7020-C-T-P4S-UL and Fafnir 2MM9120WI-CR-UL. NSK 7020CTYNSULP4 is the same envelope with a polyamide cage and standard P4 class, a related size rather than a direct interchange. NSK 7020A5 is the 25° form of the envelope, also a related size. Medium and heavy preload variants of the same number are separate parts.