Tililt

What are the dimensions of a 6307 bearing?

Answer 35 × 80 × 21 mm

The 6307 is a deep-groove ball bearing: 35 mm bore, 80 mm outside diameter, 21 mm wide.

How it is worked out

  1. Type6 → deep-groove ball bearing
  2. Series63 → series 63 · medium · dimension series 03
  3. Bore code07 → 07 × 5 = 35 mm

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

Worth knowing

In inches
1.378 × 3.150 × 0.827 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 6307-2RSH or -2RS1, FAG 6307-2RSR, NSK 6307DDU, NTN 6307LLU.
ZZ · 2Z · 2ZR
Metal shield on both sides. Less friction and more speed than a seal, but not watertight. SKF 6307-2Z, FAG 6307-2ZR, NSK and NTN 6307ZZ.
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 6307 from any maker fits the same shaft and housing. Seals, cage, clearance and quality are what differ.

Other bores in the 63 series

Same 35 mm bore, other series

Do it with your own numbers

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