Spring Parameters
Spring type
Material
Wire diameter d2.0 mm
Mean coil diameter D20.0 mm
Active coils Na8
Free length L₀80.0 mm
Max load F_max100 N
Min load F_min20 N
End condition
—
Spring rate k [N/mm]
—
Max shear stress τ [MPa]
—
Safety factor n
—
Natural freq. fn [Hz]
—
Solid length L_s [mm]
—
Buckling check
Key Design Equations
Spring rate: $k = \dfrac{Gd^4}{8D^3 N_a}$
Wahl factor: $K_W = \dfrac{4C-1}{4C-4} + \dfrac{0.615}{C}$, $C = D/d$
Max stress: $\tau = K_W \cdot \dfrac{8FD}{\pi d^3}$
Natural freq.: $f_n = \dfrac{d}{4\pi N_a D^2} \sqrt{\dfrac{G}{2\rho}} \times 1000$ Hz
CAE integration: Use the calculated k value to define SPRING elements in FEA. Verify Goodman safety margin before running detailed stress analysis. Buckling modes should be confirmed with eigen-value analysis for long springs.