MPNbase

20×47×18 mm bearings

8 models from 2 brands across 3 types share this ISO 15 envelope: 20 mm bore, 47 mm outside diameter, 18 mm width (0.787×1.850×0.709 in), 13.5 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)
2204 Self-Aligning Ball NTN open — 12.8 3.3 142
2204-E-2RS1TN9 Self-Aligning Ball SKF 2RS CN 12.7 3.4 140
2204-ETN9 Self-Aligning Ball SKF open CN 16.8 4.15 140
2204K Self-Aligning Ball NTN open — 12.8 3.3 142
4204-ATN9 Deep Groove Ball SKF open CN 17.8 12.5 140
62204-2RS Deep Groove Ball SKF 2RS CN 12.7 6.55 130
NJ2204-ECP Cylindrical Roller SKF open CN 34.5 27.5 140
NU2204-ECP Cylindrical Roller SKF open CN 34.5 27.5 140

Note: catalogue dynamic load ratings for this envelope span 12.7– 34.5 kN — a 172% spread between designs in the very same 20×47×18 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 20 mm bore bearings for wider or narrower sections, or open a model page for naming-rule decode, applications and graded cross references: 2204, 2204-E-2RS1TN9, 2204-ETN9, 2204K, 4204-ATN9, 62204-2RS, NJ2204-ECP, NU2204-ECP.

Frequently asked questions

Are all 20×47×18 mm bearings interchangeable?

They share the same ISO 15 boundary dimensions — 20 mm bore, 47 mm OD, 18 mm width (0.787×1.850×0.709 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 20×47×18?

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 20×47×18 mm in inches?

20×47×18 mm converts to 0.787×1.850×0.709 in, with a 13.5 mm (0.531 in) radial section height. These are the ISO 15 general-plan envelope dimensions shared across manufacturers, which is why models such as 2204, 2204-E-2RS1TN9, 2204-ETN9 mount in the same space despite different internal designs.