300×540×85 mm bearings

8 models from 2 brands across 3 types share this ISO 15 envelope: 300 mm bore, 540 mm outside diameter, 85 mm width (11.811×21.260×3.346 in), 120 mm radial section.

8 models fit this space 2 brands 8 with catalogue C rating

Dimensional interchange — verify before substituting

These bearings are interchangeable on boundary dimensions per ISO 15 — same bore, OD and width. They are not guaranteed drop-in equivalents: compare load ratings, seals, clearance, cage, precision and axial-locating design for the specific duty. Models without a catalogue C rating on this site carry ISO 15 geometry only; request the manufacturer table before a load-critical replacement.

Model Type Brand Seal Clearance C (kN) C0 (kN) Mass (g)
6260-M Deep Groove Ball SKF open CN 462 670 88500
7260-BCBM Angular Contact Ball SKF open CN 553 930 85000
N260 Cylindrical Roller NTN open CN 1560 2070 86400
NF260 Cylindrical Roller NTN open CN 1560 2070 86400
NJ260 Cylindrical Roller NTN open CN 1560 2070 86400
NU260 Cylindrical Roller NTN open CN 1560 2070 86400
NU260-M Cylindrical Roller SKF open CN 1420 2120 89500
NUP260 Cylindrical Roller NTN open CN 1560 2070 86400

Note: catalogue dynamic load ratings for this envelope span 462.0– 1560.0 kN — a 238% spread between designs in the very same 300×540×85 mm space. The higher-rated unit is not an upgrade for every duty (it may run at lower limiting speed), but ignoring the gap will over- or under-life the replacement.

Substitution verification checklist

  1. Load rating. Check C (dynamic) and C0 (static) against the original life calculation — the table above shows which models carry verified catalogue values.
  2. Sealing. Open, -ZZ shields and -2RS contact seals are not equivalent in friction, speed or contamination protection; match the housing environment, not just the suffix on the old box.
  3. Internal clearance. CN/C3/C4 changes with fit and operating temperature; an interference inner-ring mount commonly needs C3 where the bench bearing ran CN.
  4. Cage and precision. Stamped steel, machined brass and polymer cages, and P0/P6/P5 tolerance classes, carry different speed and shock limits.
  5. Locating behaviour. Within one envelope an NU cylindrical roller floats axially while an NJ/NUP locates; ball designs take thrust that roller locating schemes do not. Preserve the shaft's locating arrangement.

Browse all 300 mm bore bearings for wider or narrower sections, or open a model page for naming-rule decode, applications and graded cross references: 6260-M, 7260-BCBM, N260, NF260, NJ260, NU260, NU260-M, NUP260.

Frequently asked questions

Are all 300×540×85 mm bearings interchangeable?

They share the same ISO 15 boundary dimensions — 300 mm bore, 540 mm OD, 85 mm width (11.811×21.260×3.346 in) — so they fit the same shaft, housing bore and axial space. Interchangeability ends at the envelope: dynamic load rating, seal arrangement, internal clearance, cage and precision class differ between the 8 models listed here and must be checked against the duty before substitution.

Is it a drop-in replacement if two bearings both measure 300×540×85?

Only after verification. Confirm five things in order: (1) the C/C0 load ratings meet the original life calculation, (2) the seal type is equivalent or acceptable for the contamination level (open vs -ZZ vs -2RS), (3) internal clearance matches (CN/C3/C4 — an interference fit changes residual play), (4) cage material and precision class suit the speed, and (5) the axial-locating behaviour is the same (for example an NU cylindrical roller floats while an NJ locates one way). Same dimensions alone never guarantee equal performance.

What is 300×540×85 mm in inches?

300×540×85 mm converts to 11.811×21.260×3.346 in, with a 120 mm (4.724 in) radial section height. These are the ISO 15 general-plan envelope dimensions shared across manufacturers, which is why models such as 6260-M, 7260-BCBM, N260 mount in the same space despite different internal designs.