Calculator for
c
ompression springs
Diameter of spring wire d
10
-3
m
Mean coil diameter D
10
-3
m
Number of active coils n
-
Shear modulus G = E / ( 2 ( 1+v ) )
10
9
Pa
Spring force F
N
Spring outer diameter Dout = D + d
10
-3
m
Spring radius r = D / 2
10
-3
m
Spring length closed Lc = n d
10
-3
m
Spring deflection f
10
-3
m
Spring stiffness k = dF / df = F / f
10
3
N/m
Spring length free L0 > Lc + f
10
3
N/m
Pitch of lead s = L0 / n
10
-3
m
Shear stress τ
10
6
Pa
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