Helical Spring Rate

mech-spring-rate

Helical Spring Rate

mechanical

Machine Design

k = \frac{Gd^4}{8D^3n}

Spring constant for helical compression spring

Close-coiled, round-wire spring in linear elastic range

[
  {
    "symbol": "k",
    "name": "Spring Rate",
    "unit": "N/m",
    "siUnit": "N/m",
    "imperialUnit": "lbf/in"
  },
  {
    "symbol": "G",
    "name": "Shear Modulus",
    "unit": "Pa",
    "siUnit": "Pa",
    "imperialUnit": "psi"
  },
  {
    "symbol": "d",
    "name": "Wire Diameter",
    "unit": "m",
    "siUnit": "m",
    "imperialUnit": "in"
  },
  {
    "symbol": "D",
    "name": "Mean Coil Diameter",
    "unit": "m",
    "siUnit": "m",
    "imperialUnit": "in"
  },
  {
    "symbol": "n",
    "name": "Active Coils",
    "unit": "",
    "siUnit": ""
  }
]

k, G, d, D, n

spring, helical, coil, stiffness

false