EngiRef / Mechanical Engineering Formula
Helical Spring Rate
Helical Spring Rate: Spring constant for helical compression spring. A Machine Design formula in mechanical engineering. Variables k, G, d, D and n, each with…
Machine Design
Specification
- Name
- Helical Spring Rate
- Discipline
- mechanical
- Category
- Machine Design
- LaTeX
- k = \frac{Gd^4}{8D^3n}
- Description
- Spring constant for helical compression spring
- Conditions
- Close-coiled, round-wire spring in linear elastic range
- Can solve for
- k, G, d, D, n
- Tags
- spring, helical, coil, stiffness
Variables
| Symbol | Name | Unit | Si Unit | Imperial Unit |
|---|---|---|---|---|
| k | Spring Rate | N/m | N/m | lbf/in |
| G | Shear Modulus | Pa | Pa | psi |
| d | Wire Diameter | m | m | in |
| D | Mean Coil Diameter | m | m | in |
| n | Active Coils | — | — | — |