Calcolatori di molle

Compression spring calculator

Calculate spring rate, maximum safe load, deflection and solid height for your compression spring. Enter the dimensions and get engineering results instantly.

Unità
mm
mm
mm
Risultato
Costante elastica25.881 lbf/in [4.53 N/mm]
Carico massimo sicuro30.381 lbf [135.14 N]
Freccia massima sicura1.174 in [29.82 mm]
Altezza a pacco0.630 in [16.00 mm]
Indice della molla9.00
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Formula

k = G·d⁴ / (8·D³·Na)
F = k·x

Simboli

kspring rate (N/mm or lbf/in)
Gshear modulus of the material (psi or MPa)
dwire diameter (in or mm)
Dmean coil diameter: OD − d (in or mm)
Nanumber of active coils
Fforce at deflection x (lbf or N)
xdeflection from free length (in or mm)

Esempio calcolato

Dati
Diametro del filo0.079 in [2.00 mm]
Diametro esterno0.787 in [20.00 mm]
Lunghezza libera1.969 in [50.00 mm]
Spire totali8
MaterialeAcciaio al carbonio (MW)
Risultato
Costante elastica25.881 lbf/in [4.53 N/mm]
Carico massimo sicuro30.381 lbf [135.14 N]
Freccia massima sicura1.174 in [29.82 mm]

Calcolato dallo stesso motore del calcolatore sopra, con i valori iniziali del modulo.

Enter wire diameter, outer diameter, free length and coil count. The calculator applies the Wahl factor and automatically validates spring index and shear stress.

Load limits use the real allowable stress of each catalog material, so the result already tells you whether the design is manufacturable.

Need a quote? Open the same configuration in the full designer for tiered pricing and a technical drawing.

Regolazione rapida: più o meno forza

Più forza
  • Filo più spesso
  • Diametro esterno minore
  • Meno spire attive
Meno forza
  • Filo più sottile
  • Diametro esterno maggiore
  • Più spire attive

Come misurare la molla

  1. Measure the wire diameter (d) with calipers or a micrometer, away from the ends.
  2. Measure the outer diameter (OD) across the coils. The mean diameter is OD minus d.
  3. Measure the free length (FL) with no load, end to end.
  4. Count the total number of coils. Closed and ground ends reduce the active coil count.
  5. Identify the end type: closed and ground, closed, double closed or open.

Moduli e densità dei materiali

MaterialeModulo di taglio GModulo elastico EDensità
Acciaio al carbonio (MW)11.5 × 10⁶ psi (79.3 GPa)29.5 × 10⁶ psi (203.4 GPa)7.85 g/cm³
Inox 302 (SS302)10.0 × 10⁶ psi (69.0 GPa)28.0 × 10⁶ psi (193.0 GPa)7.90 g/cm³
Inox 17-7 PH (SS177)11.0 × 10⁶ psi (75.8 GPa)29.4 × 10⁶ psi (203.0 GPa)7.81 g/cm³
Inox 316 (SS316)10.0 × 10⁶ psi (69.0 GPa)28.0 × 10⁶ psi (193.0 GPa)7.98 g/cm³
Temprato in olio (OT)11.2 × 10⁶ psi (77.2 GPa)29.5 × 10⁶ psi (203.4 GPa)7.85 g/cm³
Cromo-silicio (CS)11.2 × 10⁶ psi (77.2 GPa)29.5 × 10⁶ psi (203.4 GPa)7.85 g/cm³
Trafilato duro (HD)11.5 × 10⁶ psi (79.3 GPa)29.5 × 10⁶ psi (203.4 GPa)7.85 g/cm³
Bronzo fosforoso (PB)6.0 × 10⁶ psi (41.4 GPa)14.9 × 10⁶ psi (103.0 GPa)8.86 g/cm³
Rame berillio (BC)7.0 × 10⁶ psi (48.3 GPa)18.6 × 10⁶ psi (128.0 GPa)8.25 g/cm³
Cromo-vanadio (CV)11.2 × 10⁶ psi (77.2 GPa)29.5 × 10⁶ psi (203.4 GPa)7.85 g/cm³

Domande frequenti

What is the spring rate of a compression spring?

It is the force needed to compress the spring by one unit of length, expressed in lbf/in or N/mm. A 57 lbf/in spring takes 57 lbf for every inch of compression, approximately linearly until the coils touch.

How do I make a compression spring stronger?

Increase the wire diameter (the effect scales with the fourth power), reduce the outer diameter, or reduce the number of active coils. Any of the three changes raises the spring rate.

What is solid height?

It is the length of the spring when all coils touch. The spring cannot work past that point, and healthy designs keep clearance between the maximum working deflection and solid height.

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