The meaning of each item in the formula is: G = shear elastic modulus [MPa] (G value is: carbon steel 80000, stainless steel 72000) d = wire diameter [mm, in] n = effective number of turns [-]D = center diameter [mm, in]k = spring rate [N/mm, lb/in]
This formula is the calculation formula of the spring stiffness. The stiffness multiplied by the working stroke is equal to the working force of the spring.
Through the above formula, we can conclude that the parameters of the compression spring must be composed of: material, wire diameter, center diameter, effective number of turns, total spring length, working height, and required strength. If there is no special requirement for the strength of the spring, the parameters of the working height and required strength of the spring may not be provided.
