CALCS PROC062
HELICAL SPRING ANALYSIS

NOTATION

Talphatangent, spring pitch angle
ddia, spring wire
nno. active coils
Rradius, coil, nominal
Pforce
dxdisplacement

APPLICATION

helical spring under axial loading

OUTPUT

stiffness & shear stress

SEE ALSO

other porcs & progs

THEORY

ROARK5,P319

GUIDANCE

guidance notes

INPUT FORMAT

LET Nm=:Nk=:Talpha=:d=:n=:R=:P=:PROC062

EXAMPLE

Call Statement

LET Nm=1:Nk=1:Talpha=3/13:d=.15:n=6:R=.65:P=.001:PROC062

Output

PROC062 HELICAL SPRING, Rev 170600
dx= ((64*P*R^3*n)/(G(Nm)*d^4))*(1-(3/64)*(d/R)^2+(3+v(Nm))*Talpha^2/(2*(1+v(Nm))))= 0.2787
K= P/dx= 3.588E-3
fs= ((16*P*R)/(PI*d^3))*(1+(5/8)*(d/R)+(7/32)*(d/R)^2)= 1.134
UF= fs/(Fy(Nm)*Ks(Nk))= 0.8336
END062