6028-NTN bearing: complete specifications & equivalents
The 6028-NTN 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.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| 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 | 122 kN |
| Basic static load rating C0 | 109 kN |
| Fatigue load limit Pu | 5.85 kN |
| Limiting speed (mechanical) | 3000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 3350 g |
| Manufacturer designation | 6028 |
| Standard | ISO 15 |
| Catalog version | NTN Ball and Roller Bearings CAT.No.2203-3/E (2024) |
| Last verified | 2026-09-25 |
Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203-3/E (2024)) · extracted 2026-09-25
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203-3/E (2024)); NTN® is a trademark of NTN Corporation, used here for identification only — mpnbase is not an authorized NTN distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at ntnglobal.com.
Dimensions in inches & 6000-series range
| Bore d | 5.512 in |
|---|---|
| Outer diameter D | 8.268 in |
| Width B | 1.299 in |
| ISO bore code | 28 |
| Radial section height (D−d)/2 | 35 mm |
| Smallest bore in 6000-series | 4 mm |
| Largest outer diameter in 6000-series | 1150 mm |
| Width range across 6000-series | 4–155 mm |
| Bore position in 6000-series (smallest first) | 32 of 61 |
| Bore above smallest 6000-series size | 136 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 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. |
| 6028-2RS-NSK | NSK | 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-NSK | NSK | 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-NSK | NSK | 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 | 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-NTN model number is decoded
6028 is supplied open, without shields or seals, so the arrangement around it must supply and retain the lubricant. 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. In the NTN catalogue this open execution carries the bare designation; protected variants are ordered separately with suffixes ZZ (shields), LLB/LLF (non-contact seals), LLH (low-torque contact seal) and LLU (contact seal).
Typical equipment & failure modes
Common applications
- medium and heavy industrial drives
- large gearboxes
- industrial fans and blowers
- hoists and winches
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
- 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.
- 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.
- Storage matters for open bearings: 6028-NTN 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.
- Open bearings tolerate the highest speeds in the 6000-series but need a defined regreasing interval; run-to-failure lubrication is the dominant cause of early failure in open 6028 units.
- Grease compatibility is not guaranteed between fills: mixing lithium and polyurea thickeners in a 6000-series position can soften the mixture and leak — clean out the old fill before switching grease types.
- Axial location must clamp the ring face, not the seal area: a shoulder or circlip bearing on the seal side of the 33 mm-wide ring of 6028-NTN drags the lip and overheats it.
- The open 6028 has no integral sealing; in the NTN 2203 catalogue the protected variants carry suffixes ZZ (non-contact steel shields), LLB/LLF (non-contact rubber seals), LLU (contact rubber seals) and LLH (a low-torque contact seal with higher speed capability than LLU). A JR or JRX suffix (printed for some thin-section sizes) denotes a pressed-steel cage, not a seal.
- The 140 mm bore places 6028 at the lower end of NTN's large-size range; at these diameters the pressed-steel cage is speed-limited and NTN commonly supplies a machined brass cage (suffix M) as an option. Verify cage material and relubrication interval with the NTN distributor, and do not extrapolate small-bore speed ratings to this size.
- NTN lists the grease limiting speed at 3000 r/min for 6028; this is a large or heavy-section size where centrifugal force and cage inertia cap the speed — for higher shaft speeds either step to a smaller bearing on the same bore or consult NTN for an oil-lubricated, machined-cage variant.
- At 122 kN dynamic load rating (C) and 109 kN static (C0), 5.85 kN fatigue load limit Cu, 6028 is a heavy-load bearing for industrial gearboxes and large conveyors; NTN 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 3350 g (3.4 kg), 6028 needs mechanical handling for mounting; NTN 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 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 122/109 kN load ratings, 5.85 kN fatigue load limit Cu NTN lists the grease limiting speed at 3000 r/min for this designation; oil-mist or jet lubrication raises the ceiling but requires a sealed-housing review. and 3350 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E 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.
- NTN's pressed-steel cage (no cage suffix) is the quiet standard for this size; for sustained running close to the limiting speed or for heavy shock duty, ask the NTN channel whether a machined-cage execution of 6028 is listed.
- Two NTN bearings of the same designation from different production lots can carry minor internal-geometry revisions; for paired or preloaded arrangements on one shaft, order a single lot through the NTN distributor.
Frequently asked questions
What are the dimensions of a 6028-NTN bearing?
A 6028-NTN 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 internal clearance does 6028-NTN have?
Unless a clearance suffix says otherwise, 6028-NTN is manufactured to normal (CN) radial internal clearance. Tight fits and hot shafts consume clearance in service — for those conditions order the C3 execution of 6028 and verify the residual clearance after mounting.
How should 6028-NTN be mounted?
Apply the mounting force to the ring being fitted: on a 140 mm shaft seat the press load must pass through the inner-ring face only. Induction heating of the inner ring (max 120 °C) is the clean method at this size. Never strike the outer ring, the cage or the seals.
What is the NTN order number for an open 6028?
NTN lists the open 6028 under the bare designation 6028; protected versions use suffixes ZZ (shields), LLB/LLF (non-contact seals), LLH (low-torque contact seal) and LLU (contact seal) on the same 140 mm bore envelope.
Does NTN offer 6028 with C3 clearance?
Yes — most NTN deep-groove sizes can be ordered with C3 internal clearance (suffix C3 follows the seal code). C3 suits tight fits and hot shafts; for normal fits at moderate temperature the standard CN clearance of 6028 is the correct choice.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN Ball and Roller Bearings CAT.No.2203-3/E (2024) on 2026-09-25. Read our editorial & correction policy.