Compression / tension spring (A)
Deflection, stiffness, shear stress and stored energy of a helical compression/tension spring, from wire diameter, coil diameter, number of coils and shear modulus.
Spring outer diameter, D_out = D + d14 10⁻³ m
Spring radius, r = D/26 10⁻³ m
Spring length closed (solid), L_c = nd60 10⁻³ m
Spring deflection, f32.69 10⁻³ m
Energy stored, W = Ff/21.63 J
Spring stiffness, k = dF/df = F/f3.06 10³ N/m
Free spring length, L0 > L_c + f92.69 10⁻³ m
Pitch of lead, s = L0/n3.09 10⁻³ m
Shear stress, τ381.97 10⁶ Pa
Method & references
- Helical compression/tension spring — deflection, stiffness and shear stress.
The computation is a literal port of the original client-side JavaScript from /calculators/t14_1.htm. Results are verified equal to the original by an automated golden-master test. No formula has been re-derived or “improved”.