6028-ZZ-NSK bearing: complete specifications & equivalents

Specification table

Source: catalog reference (NSK Rolling Bearings E1103 Part C) · extracted 2026-09-24

Cross references & equivalents

Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.

How the 6028-ZZ-NSK model number is decoded

6028-ZZ carries two non-contact sheet-steel shields that hold the factory grease in and keep coarse debris out; they do not seal against liquids. Within the extra-light 60xx section (diameter series 0 of ISO 15), multiplying bore code 28 by five gives the 140 mm bore; the 210 mm outside diameter and 33 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 140 mm shaft under normal load, catalogue practice seats it on a m6 shaft fit with an H7 housing bore — confirm against the actual load direction and magnitude before committing. NSK catalogue order number: 6028ZZ (suffix ZZ), two non-contact steel shields, mapped here from the industry-neutral -ZZ spelling.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Mount this 140 mm bore bearing by heating the inner ring (induction heater, max 120 °C) — never drive it home through the outer ring or balls, that brinells the raceways.
• The 60xx extra-light section at 140 mm bore uses a smaller 210 mm OD than a 6228; load ratings are lower, so do not replace a failed 62-series bearing with a 60-series without re-rating the load.
• Do not wash 6028-ZZ-NSK in solvent before mounting: the grease inside the shielded cavity is the service fill, and solvent creeping past the shield gap strips it out.
• Shielded 6028-ZZ-NSK units are typically greased for life; prying the shields out for regreasing usually bends them and leaves a gap that throws grease in service.
• Do not quieten a noisy bearing by preloading it: the 6000-series is a deep-groove design, not angular-contact; axial preload raises temperature and shortens grease life.
• Measure the shaft, do not trust the drawing: a 140 mm nominal journal worn by even 0.02 mm turns an interference seat into a creeping fit that frets the bore of 6028-ZZ-NSK.
• NSK catalogues the shielded version as 6028ZZ — suffix ZZ, two non-contact steel shields. The industry-neutral page spelling is -ZZ; quote the NSK order number when buying through an NSK channel.
• The 140 mm bore places 6028 at the lower end of NSK's large-size range; at these diameters the pressed-steel cage is speed-limited and NSK commonly supplies a machined brass cage (suffix M) as an option. Verify cage material and relubrication interval with the NSK distributor, and do not extrapolate small-bore speed ratings to this size.
• At 121 kN dynamic load rating (C) and 109 kN static (C0), 6028 is a heavy-load NSK bearing for industrial gearboxes and large conveyors; NSK expects a machined brass cage (suffix M) at this rating for shock duty, and the static C0 must be checked against any mounting or lifting loads.
• At 3480 g (3.5 kg), 6028 needs mechanical handling for mounting; NSK recommends induction heating the inner ring (max 120 °C) rather than pressing cold, and a lifting eye if the housing is pre-assembled.
• The 140×210×33 mm envelope of 6028 gives a D/d ratio of 1.50 and 35.0 mm radial section height — this NSK thin section saves space but is sensitive to misalignment and shock; confirm the housing stays round within IT7 and the shaft does not deflect past the raceway contact angle under load.
• The 121/109 kN load ratings, mass 3480 g here are NSK Rolling Bearings E1103 Part C catalogue figures for 6028ZZ on the 140×210×33 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 6028 in a rated drive. NSK does not tabulate reference or limiting speeds in the E1103 Part C dimension tables used for this page — consult NSK's separate speed-rating tables before high-speed service.
• Standard P0 runout from NSK is adequate up to the catalogue limiting speed on ground shaft seats; spindle or instrument positions should specify P6/P5 accuracy explicitly — it is a different order code, not a sorting of standard stock.
• NSK's VV non-contact seal keeps frictional torque close to the open 6028; in motor duty where heat build-up matters, VV is the usual compromise between debris protection and speed capability.