TOOTH bending strength ( ISO 6336-3)
pinion
gear
number of teeth z >= 12
profile shift coeff. x=V/m
n
= 0...0.5
module m
mm
pressure angle (ISO)
deg.
face width b
mm
permissible tooth-root stress test gear σ
F lim
(table)
MPa
factor σ
FP
/ σ
F lim
= (Y
ST
· Y
NT
· Y
δ
·Y
R
·Z
X
) / S
F
load factor σ
F
/ σ
F0
= K
A
· K
v
· K
Fα
·K
Fβ
pinion
gear
diameter d=m·z
mm
mm
diameter roll circle d
w
mm
mm
form factor Y
Fa
stress correction factor Y
Sa
center distance a
mm
contact ratio ε
α
contact ratio factor Y
ε
permissible tooth-root stress σ
FP
MPa
roll pressure angle α
w
deg.
Max tangential force F
t max
kN
kN
Max torque pinion T
max
=F
t max
·d
w
/ 2
Nm
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