HELICAL SPRINGS
FOLLOWING DIN EN 13906-1,2,3
Order : Dware
Project : HeliSpring
Subproject : Dimensioning Torsion Spring
Project item : Spring for Sectional Car Port
Spring ID : 60x1200
Calculated by : André Dewispelaere
Organization : Dware
Date : 03.12.2025 




   Spring wire grade




 Nr, Cl, Spring Wire Grade       ,      E,     G,  rho,  Rm1, Rco




230, FD, EN 10270-2 FDSiCr       , 206000, 79500, 7.85, 2000, 320
1 Calculated wire properties Symbol Unit Value
2 Wire diameter d mm 7.000
3 Minimal ultimate tensile strength Rm N/mm˛ 1730
4 Module of rigidity G N/mm˛ 79500
5 Module of Elasticity E N/mm˛ 206000

1 Design Specifications Symbol Unit Value
2 Minor torsional moment M1 Nm 8.000
3 Major torsional moment M2 Nm 32.200
4 Major number wind up revolutions nrev2 rev 7.000
5 Number of load cycles Ncy Mcy 0.010
6 Inside diameter not less than Di mm 46.00
7 Approximate coil space unloaded a mm 0.00
8 Forming -- -- cold
9 Hand of coiling -- -- right
10 Shot peening -- -- Yes
11 Calculation of geometry Symbol Unit Value
12 Calculated wire diameter dc mm 6.56
13 Selected wire diameter d mm 7.000
14 Minimum diameter of wire dmin mm 6.350
15 Choosen mean diameter of coil D mm 53.00
16 Spring index w -- 7.57
17 Outside diameter of spring De mm 60.00
18 Inside diameter of spring Di mm 46.00
19 Choosen coil pitch unloaded m0 mm 7.100
20 Resulting coil space unloaded a mm 0.100
21 Permiss max space between coils amax mm 12.77
22 Choosen number of active coils n -- 168.00
23 Body length when unloaded LW mm 1199.8
24 Length of evolved active coils l mm 27998
25 Angular spring rate RMRv Nm/rev 5.450
26 Type of spring end A ETA -- rad inside
27 Number of inactive coils A nnaA -- 0.00
28 Distance of force action point LFA mm 16.0
29 Length of end A lA mm 7.0
30 Inner bending radius end A rA mm 7.0
31 Major force acting on spring end FA N 2012.500
32 Type spring end B ETB -- rad inside
33 Number of inactive coils B nnaB -- 0.00
34 Distance force action point LFB mm 16.0
35 Length of end B lB mm 7.0
36 Inner bending radius of end B rB mm 7.0
37 Major force acting on spring end FB N 2012.500
38 Total number of coils nt -- 168.00
39 Total free state body length L0 mm 1199.8
40 Calculation spring diagram Symbol Unit Value
41 Minor torsional moment M1 Nm 8.000
42 Minor torsion angle nrev1 rev 1.468
43 Major torsional moment M2 Nm 32.200
44 Major torsion angle nrev2 rev 5.909
45 Permissible max torsional moment Mn Nm 36.380
46 Permissible max torsion angle nrevn rev 6.680
47 Strength calculation Symbol Unit Value
48 Stress correction factor q -- 1.120
49 Corrected minor bending stress σbq1 N/mm˛ 266
50 Ccorrected major bending stress σbq2 N/mm˛ 1071
51 Permissible static bending stress σbP N/mm˛ 1210
52 Safety factor stat bending stress SF -- 1.27
53 Strength domain -- -- static
54 Permissible endurance stress σeN N/mm˛ 1210
55 Permissible upper bending stress σbqO N/mm˛ 1210
56 Safety factor on upper bend stress SFO -- 1.13
57 Torsion stroke bending stress σbqh N/mm˛ 805
58 Permissible stroke bending stress σbH N/mm˛ 944
59 Safety factor stroke stress SFH -- 1.17
60 Length of wire and mass Symbol Unit Value
61 Evolved length of wire lw mm 28031
62 Spring mass mw g 8468
63 Spring work Symbol Unit Value
64 Minor spring work W1 J 36.895
65 Major spring work W2 J 597.719
66 Work exchange DW J 560.824