6028-NSK bearing: complete specifications & equivalents

The 6028-NSK is a ISO 15 radial bearing sized 140 x 210 x 33 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.

Bearing dimension schematic Front view shows outer diameter D and bore d; side section shows width B. D = 210 mm d = 140 B = 33 mm side section front view
Principal dimensions: bore d 140 mm, outer diameter D 210 mm, width B 33 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand NSK
Bore diameter d 140 mm
Outer diameter D 210 mm
Width B 33 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage steel, stamped ribbon (J-type)
Basic dynamic load rating C 121 kN
Basic static load rating C0 109 kN
Operating temperature -40 to +150 °C
Mass 3480 g
Manufacturer designation NSK 6028
Standard ISO 15
Catalog version NSK Rolling Bearings E1103 Part C
Last verified 2026-09-24

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

Dimensions in inches & 6000-series range

Bore d5.512 in
Outer diameter D8.268 in
Width B1.299 in
ISO bore code28
Radial section height (D−d)/235 mm
Smallest bore in 6000-series4 mm
Largest outer diameter in 6000-series1150 mm
Width range across 6000-series4–155 mm
Bore position in 6000-series (smallest first)32 of 61
Bore above smallest 6000-series size136 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
6028-FAG FAG full
Dimensions and internal design equivalent — standard interchange.
Same 140×210×33 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6028-2RS-FAG FAG partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 140×210×33 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6028-ZZ-FAG FAG partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 140×210×33 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6028-NTN NTN full
Dimensions and internal design equivalent — standard interchange.
Same 140×210×33 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6028-2RS-NTN NTN partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 140×210×33 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6028-ZZ-NTN NTN partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 140×210×33 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6028 SKF full
Dimensions and internal design equivalent — standard interchange.
Same 140×210×33 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6028-2RS SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 140×210×33 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6028-ZZ SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 140×210×33 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6028-M SKF full
Dimensions and internal design equivalent — standard interchange.
Same 140×210×33 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.

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-NSK model number is decoded

In the 6000-series (diameter series 0 of ISO 15) the last two digits encode the bore: 6028 carries bore code 28 = 140 mm. Outside diameter 210 mm and width 33 mm come from the ISO 15 boundary-dimensions general plan. With no seal suffix the bearing is open: no shields or seals are fitted and lubrication is supplied by the application. For normal-load mounting with a rotating inner ring on a 140 mm shaft, typical catalogue practice is a m6 shaft seat with an H7 housing bore — verify against the actual load direction and magnitude. In the NSK catalogue this open execution carries the bare designation; protected variants are ordered separately with suffixes ZZ (steel shields), VV (non-contact rubber seals) and DDU (contact rubber seals).

Typical equipment & failure modes

Common applications

  • pulp and paper machinery
  • medium and heavy industrial drives
  • large gearboxes
  • industrial fans and blowers

Known failure patterns

  • contamination wear from dust and dirt ingress through the open arrangement
  • lubricant starvation when no regreasing interval is maintained
  • raceway smearing under marginal lubrication at start-up
  • edge loading from shaft deflection or housing misalignment

Selection pitfalls — read before you substitute

  • At 140 mm bore the ring mass is significant: heat 6028 on an induction heater (max 120 °C), never over an open flame, and plan puller access or a withdrawal sleeve now for the day it has to come off again.
  • Choosing the 60xx extra-light section saves radial space at 140 mm bore, but the trade-off is rating: if the drive sees shock or frequent start-stop cycles, re-check the L10 life against a 6228 before committing to the smaller envelope.
  • The open 6028-NSK has no lubricant retention: grease escapes and contaminants migrate straight into the 140×210×33 mm raceway, so specify a sealed arrangement for dusty or washdown duty.
  • Storage matters for open bearings: 6028-NSK leaves the factory with rust preventive only, so clean it and apply the service grease at assembly even if the rings look oily from the wrapper.
  • Deep-groove ball bearings tolerate only minutes of misalignment; if the 210 mm housing cannot be aligned, switch to a self-aligning type rather than shimming 6028-NSK.
  • Shaft and housing fillets must clear the bearing chamfer so the 33 mm-wide ring seats square; provide an undercut or withdrawal groove instead of relying on an oversized radius.
  • The open 6028 has no integral sealing; in the NSK E1103 catalogue the protected variants carry suffixes ZZ (non-contact steel shields), VV (non-contact rubber seals) and DDU (contact rubber seals). NSK does not offer a low-torque contact seal equivalent to NTN's LLH in this catalogue — for high-speed sealed duty specify the VV non-contact seal and an external housing labyrinth.
  • 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 6028 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.
  • NSK supplies its sealed units pre-greased for general duty between roughly -10 and +110 °C; low-temperature, food-grade and high-temperature fills are special executions — ask at order time, because DDU/VV units are not designed to be opened and repacked.
  • Keep NSK bearings in the original packaging until fitting: the wrapper carries the production lot, and the unopened shelf life of greased sealed units is typically quoted at three to five years in dry, vibration-free storage.

Frequently asked questions

What are the dimensions of a 6028-NSK bearing?

A 6028-NSK deep-groove ball bearing has a 140 mm bore, 210 mm outer diameter and 33 mm width (5.512 × 8.268 × 1.299 in), per ISO 15 boundary dimensions. It is an open bearing with no seals or shields.

What lubrication does 6028-NSK need?

The open 6028-NSK is lubricated by the application; a NLGI 2 lithium-soap grease filled to roughly 25–35% of the free volume is the common choice, with a defined relubrication interval.

How does the 6028 bore code work?

The last two digits of 6028 are bore code 28, giving 28 × 5 = 140 mm bore. The 210 mm outside diameter and 33 mm width follow the ISO 15 diameter series, not the bore code alone.

What is the NSK order number for an open 6028?

NSK lists the open 6028 under the bare designation 6028; protected versions use suffixes ZZ (steel shields), VV (non-contact rubber seals) and DDU (contact rubber seals) on the same 140 mm bore envelope.

Does the manufacturing plant affect 6028?

NSK produces standard deep-groove sizes in several plants worldwide to the same drawing; the origin on the box label does not change the ISO 15 envelope or the E1103 catalogue ratings quoted here.

Reviewed & verified by the MPN Base engineering desk against source catalog NSK Rolling Bearings E1103 Part C on 2026-09-24. Read our editorial & correction policy.