6001-NSK bearing: complete specifications & equivalents

The 6001-NSK is a ISO 15 radial bearing sized 12 x 28 x 8 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 = 28 mm d = 12 B = 8 mm side section front view
Principal dimensions: bore d 12 mm, outer diameter D 28 mm, width B 8 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand NSK
Bore diameter d 12 mm
Outer diameter D 28 mm
Width B 8 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage steel, stamped ribbon (J-type)
Basic dynamic load rating C 5.6 kN
Basic static load rating C0 2.37 kN
Operating temperature -40 to +150 °C
Mass 22 g
Manufacturer designation NSK 6001
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 d0.472 in
Outer diameter D1.102 in
Width B0.315 in
ISO bore code01
Radial section height (D−d)/28 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)8 of 61
Bore above smallest 6000-series size8 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
6001-FAG FAG full
Dimensions and internal design equivalent — standard interchange.
Same 12×28×8 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6001-2RS-FAG FAG partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 12×28×8 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6001-ZZ-FAG FAG partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 12×28×8 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6001-NTN NTN full
Dimensions and internal design equivalent — standard interchange.
Same 12×28×8 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6001-2RS-NTN NTN partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 12×28×8 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6001-RSR-NTN NTN partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 12×28×8 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6001-ZZ-NTN NTN partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 12×28×8 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6001 SKF full
Dimensions and internal design equivalent — standard interchange.
Same 12×28×8 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6001-2RS SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 12×28×8 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6001-RSR SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 12×28×8 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6001-ZZ SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 12×28×8 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
W6001-2RS SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 12×28×8 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
W6001-ZZ SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 12×28×8 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
W6001 SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 12×28×8 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 6001-NSK model number is decoded

6001 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 12 by five gives the 12 mm bore; the 28 mm outside diameter and 8 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 12 mm shaft under normal load, catalogue practice seats it on a j5 shaft fit with an H7 housing bore — confirm against the actual load direction and magnitude before committing. 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

  • gearboxes and speed reducers
  • conveyor drives
  • material-handling equipment
  • industrial fans

Known failure patterns

  • contamination wear from dust and dirt ingress through the open arrangement
  • lubricant starvation when no regreasing interval is maintained
  • cage damage from operation beyond the limiting speed
  • electrical pitting in VFD-driven motors without grounding protection

Selection pitfalls — read before you substitute

  • At 12 mm bore, induction heating to roughly 80–100 °C is the clean mounting method; never exceed 120 °C, and hold 6001 against the shaft shoulder while it cools so the ring cannot creep back.
  • Choosing the 60xx extra-light section saves radial space at 12 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 6212 before committing to the smaller envelope.
  • Storage matters for open bearings: 6001-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.
  • 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 6001 units.
  • Suffixes stack in a defined order — clearance follows the seal code, e.g. 6001-NSK-C3. No clearance suffix means normal CN clearance.
  • Deep-groove ball bearings tolerate only minutes of misalignment; if the 28 mm housing cannot be aligned, switch to a self-aligning type rather than shimming 6001-NSK.
  • The open 6001 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.
  • At 12 mm bore the 6001 sits in NSK's small-bore range; NSK ships these sizes with a pressed-steel cage and P0 tolerance as standard, and NSK's EA (extra-precision) or P5 class is a special-order upgrade for spindle duty — do not assume catalogue P0 figures hold for instrument use without an NSK engineering check.
  • NSK rates 6001 at 5.6 kN dynamic (C) and 2.37 kN static (C0); this light-to-medium rating suits fractional-horsepower drives and instruments — for conveying or gearbox duty with shock loads, verify the equivalent dynamic load stays well below C.
  • At only 22 g, 6001 is a lightweight NSK bearing that can be handled by hand; still, press it onto the shaft with a sleeve against the inner ring — never through the balls or outer ring.
  • The 12×28×8 mm envelope of 6001 gives a D/d ratio of 2.33 and 8.0 mm radial section height — a heavy NSK section built for high-load, lower-speed duty; specifying it in a high-rpm motor generates excess heat and shortens grease life, so prefer a 62/63-series there.
  • The 5.6/2.37 kN load ratings, mass 22 g here are NSK Rolling Bearings E1103 Part C catalogue figures for 6001 on the 12×28×8 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 6001 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.
  • NSK's VV non-contact seal keeps frictional torque close to the open 6001; in motor duty where heat build-up matters, VV is the usual compromise between debris protection and speed capability.

Frequently asked questions

What are the dimensions of a 6001-NSK bearing?

A 6001-NSK deep-groove ball bearing has a 12 mm bore, 28 mm outer diameter and 8 mm width (0.472 × 1.102 × 0.315 in), per ISO 15 boundary dimensions. It is an open bearing with no seals or shields.

How should 6001-NSK be mounted?

Apply the mounting force to the ring being fitted: on a 12 mm shaft seat the press load must pass through the inner-ring face only. A fitting sleeve and an arbor press are normally sufficient at this size. Never strike the outer ring, the cage or the seals.

What lubrication does 6001-NSK need?

The open 6001-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.

What is the NSK order number for an open 6001?

NSK lists the open 6001 under the bare designation 6001; protected versions use suffixes ZZ (steel shields), VV (non-contact rubber seals) and DDU (contact rubber seals) on the same 12 mm bore envelope.

Does NSK offer 6001 with C3 clearance?

NSK lists C3 (and C4) internal-clearance options for most deep-groove sizes under the same base designation; the clearance is fixed at manufacture, so specify it at order time rather than planning to adjust later.

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.