Koyo
FOR REFERENCE ONLY
  • Deep groove ball bearings
  • Extra-small, miniature ball bearings
  • Standard type
  • Open
>

Bearing No. 639

Specifications
(Boundary dimensions ...etc)

d(mm)9
D(mm)30
B(mm)10
r(min.)(mm)0.6
Basic load ratings : Cr(kN)7.50
Basic load ratings : C0r(kN)2.65
Fatigue load limit : Cu(kN)0.210
factor : f0()12.3
Limiting speeds(Grease lub.)(min-1)24000
Limiting speeds(Oil lub.)(min-1)29000

Mounting dimensions

da(min.)(mm)13
Da(max.)(mm)26
ra(max.)(mm)0.6

Refer.

(Refer.)Mass(g) 35
JTEKT

2025/06/18