6011-NTN bearing: complete specifications & equivalents

The 6011-NTN is a ISO 15 radial bearing sized 55 x 90 x 18 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 = 90 mm d = 55 B = 18 mm side section front view
Principal dimensions: bore d 55 mm, outer diameter D 90 mm, width B 18 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand NTN
Bore diameter d 55 mm
Outer diameter D 90 mm
Width B 18 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage steel, stamped ribbon (J-type)
Basic dynamic load rating C 31.5 kN
Basic static load rating C0 21.2 kN
Fatigue load limit Pu 1.62 kN
Limiting speed (mechanical) 7700 rpm
Operating temperature -40 to +120 °C
Mass 388 g
Manufacturer designation 6011
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 d2.165 in
Outer diameter D3.543 in
Width B0.709 in
ISO bore code11
Radial section height (D−d)/217.5 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)18 of 61
Bore above smallest 6000-series size51 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
6011-FAG FAG full
Dimensions and internal design equivalent — standard interchange.
Same 55×90×18 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6011-2RS-FAG FAG partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 55×90×18 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6011-ZZ-FAG FAG partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 55×90×18 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6011-2RS-NSK NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 55×90×18 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6011-RSR NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 55×90×18 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6011-ZZ-NSK NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 55×90×18 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6011-NSK NSK full
Dimensions and internal design equivalent — standard interchange.
Same 55×90×18 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6011 SKF full
Dimensions and internal design equivalent — standard interchange.
Same 55×90×18 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6011-ZZ SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 55×90×18 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6011-2RS SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 55×90×18 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6011-M SKF full
Dimensions and internal design equivalent — standard interchange.
Same 55×90×18 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 6011-NTN model number is decoded

6011 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 11 by five gives the 55 mm bore; the 90 mm outside diameter and 18 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 55 mm shaft under normal load, catalogue practice seats it on a k5 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

  • centrifugal and positive-displacement pumps
  • gearboxes and speed reducers
  • conveyor drives
  • material-handling equipment

Known failure patterns

  • contamination wear from dust and dirt ingress through the open arrangement
  • lubricant starvation when no regreasing interval is maintained
  • fretting corrosion on a loose shaft seat
  • cage damage from operation beyond the limiting speed

Selection pitfalls — read before you substitute

  • Temperature rise and interference fits consume internal clearance on this 55 mm bore: a CN bearing on a tight, hot shaft can lose all residual clearance — size 6011 with C3 for those conditions.
  • The 60xx extra-light section at 55 mm bore uses a smaller 90 mm OD than a 6211; load ratings are lower, so do not replace a failed 62-series bearing with a 60-series without re-rating the load.
  • Storage matters for open bearings: 6011-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 6011 units.
  • Shaft and housing fillets must clear the bearing chamfer so the 18 mm-wide ring seats square; provide an undercut or withdrawal groove instead of relying on an oversized radius.
  • 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.
  • The open 6011 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.
  • At 55 mm bore 6011 is in NTN's upper general-purpose range; the pressed-steel cage is standard but mid-section 63xx sizes at this bore can be ordered with a machined brass cage (suffix M) for heavy-shock or very-low-speed duty — confirm cage material with the NTN channel if the application sees impact loads.
  • At 7700 r/min the grease limiting speed for 6011 covers medium-duty industrial drives; the open or shielded execution can run continuously at this speed with standard lithium-soap grease.
  • At 31.5 kN dynamic load rating (C) and 21.2 kN static (C0), 1.62 kN fatigue load limit Cu, 6011 is a medium-load bearing suitable for most electric-motor and pump duty; the C0/C0r ratio matters for preloaded or thrust-loaded arrangements, so confirm the static safety factor with the NTN catalogue.
  • At 388 g, 6011 requires a soft-jaw vise or arbor press for mounting — never hammer it onto the shaft, and support the opposite ring to avoid brinelling the raceways.
  • The 55×90×18 mm envelope of 6011 gives a D/d ratio of 1.64 and 17.5 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 31.5/21.2 kN load ratings, 1.62 kN fatigue load limit Cu NTN lists the grease limiting speed at 7700 r/min for this designation; oil-mist or jet lubrication raises the ceiling but requires a sealed-housing review. and 388 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 6011 on the 55×90×18 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 6011 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 6011 is listed.
  • Order the C3 internal-clearance version (6011 with C3 after the seal code) when the shaft fit is tight or the shaft-to-housing temperature gradient exceeds roughly 10 °C — the residual clearance after mounting, not the catalogue CN figure, decides service life.

Frequently asked questions

What are the dimensions of a 6011-NTN bearing?

A 6011-NTN deep-groove ball bearing has a 55 mm bore, 90 mm outer diameter and 18 mm width (2.165 × 3.543 × 0.709 in), per ISO 15 boundary dimensions. It is an open bearing with no seals or shields.

What lubrication does 6011-NTN need?

The open 6011-NTN 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 6011 bore code work?

The last two digits of 6011 are bore code 11, giving 11 × 5 = 55 mm bore. The 90 mm outside diameter and 18 mm width follow the ISO 15 diameter series, not the bore code alone.

What is the NTN order number for an open 6011?

NTN lists the open 6011 under the bare designation 6011; protected versions use suffixes ZZ (shields), LLB/LLF (non-contact seals), LLH (low-torque contact seal) and LLU (contact seal) on the same 55 mm bore envelope.

Does NTN offer 6011 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 6011 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.