Tililt

What are the dimensions of a 6901 bearing?

Answer 12 × 24 × 6 mm

The 6901 is a deep-groove ball bearing: 12 mm bore, 24 mm outside diameter, 6 mm wide.

How it is worked out

  1. Type6 → deep-groove ball bearing
  2. Series69 → series 69 · thin-section · dimension series 19
  3. Bore code01 → 12 mm (fixed by the standard)

d = bore code × 5 mm (04+) · 00 = 10 · 01 = 12 · 02 = 15 · 03 = 17 mm

Worth knowing

In inches
0.472 × 0.945 × 0.236 in. A metric bearing: inch-series bearings (R8, 1600…) do not fit the same shaft.
2RS · 2RS1 · 2RSH · DDU · LLU
Rubber seal on both sides, greased for life. Best against dirt and water, slightly more drag. The same bearing by brand: SKF 6901-2RSH or -2RS1, FAG 6901-2RSR, NSK 6901DDU, NTN 6901LLU.
ZZ · 2Z · 2ZR
Metal shield on both sides. Less friction and more speed than a seal, but not watertight. SKF 6901-2Z, FAG 6901-2ZR, NSK and NTN 6901ZZ.
RS · Z
Seal (RS) or shield (Z) on one side only, the other side open: for bearings fed oil or grease by the machine.
C3
Internal clearance larger than normal. Standard on electric motors and wherever the shaft runs hot or the fit is tight. Replace a C3 with a C3.
Interchangeable?
Yes. ISO 15 fixes the bore, outside diameter and width, so a 6901 from any maker fits the same shaft and housing. Seals, cage, clearance and quality are what differ.

Other bores in the 69 series

Same 12 mm bore, other series

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