Helical Compression Spring Design Equations and Calculator
This Helical Compression Spring Design Equation will determine force from the given variables.
Force (F) = k(DStanding - DDeflected)
Where:F = Force exerted on spring (lbs)
DStanding = Free length of spring (inches)
DDeflected= Length of spring with force applied (inches)
k = Spring constant determined by experiment or calculation (Calculate k Constant)
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Compression Spring Design Suggestions:
Spring rate can be measured by taking the difference in force at 80% maximum deflection and 20% minimum deflection and dividing by the difference in deflection. The spring rate tends to be constant over the central 60 percent of the deflection range. Because of end-coil effects, the first 20% of deflection range has a considerably lower spring rate. The final 20% of deflection shows considerably higher spring rate. When designing for a particular spring, design for critical loads and rates to be within the central 60% deflection range. Standard and custom springs are available.