Parameter 
Formula 
Spring outer diameter [OD] 

Spring inner diameter [ID] 

Spring index [C] 

Spring index 1 [C_{1}] 

Curvature correction factor for point A [K_{A} ] 

Tensile stress at point A [σ_{A}] 

Spring index 2 [C_{2}^{+}] 

Stress correction factor for point B [K_{B} ] 

Shear stress at point B [σ_{B}] 

Wahl factor [K_{w}] 

Shear stress at spring body [τ_{sb}] 

Factor of safety at point A [fos_{A}] 

Factor of safety at point B [fos_{B}] 

Factor of safety at spring body [fos_{sb}] 
