What are the dimensions of a 6905 bearing?
Answer
The 6905 is a deep-groove ball bearing: 25 mm bore, 42 mm outside diameter, 9 mm wide.
How it is worked out
- Type
6 → deep-groove ball bearing - Series
69 → series 69 · thin-section · dimension series 19 - Bore code
05 → 05 × 5 = 25 mm
d = bore code × 5 mm (04+) · 00 = 10 · 01 = 12 · 02 = 15 · 03 = 17 mm
Worth knowing
- In inches
- 0.984 × 1.654 × 0.354 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 6905-2RSH or -2RS1, FAG 6905-2RSR, NSK 6905DDU, NTN 6905LLU.
- ZZ · 2Z · 2ZR
- Metal shield on both sides. Less friction and more speed than a seal, but not watertight. SKF 6905-2Z, FAG 6905-2ZR, NSK and NTN 6905ZZ.
- 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 6905 from any maker fits the same shaft and housing. Seals, cage, clearance and quality are what differ.
Other bores in the 69 series
Same 25 mm bore, other series
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