TABLE OF CONTENTS Robert E. Joerres
Applications Engineering Manager
Associated Spring, Barnes Group, Inc.
Bristol, Connecticut
| A | Area, mm 2 (in 2) | |
| b | Width, mm (in) | |
| C | Spring index, D/d | |
| d | Wire diameter, mm (in) | |
| D | Mean diameter (OD minus wire diameter), mm (in) | |
| E | Modulus of elasticity in tension or Young s modulus, MPa (psi) | |
| f | Deflection, mm (in) | |
| g | Gravitational constant, 9.807 m/s 2 (386.4 in/s 2) | |
| G | Shear modulus or modulus of rigidity, MPa (psi) | |
| I | Moment of inertia, mm 4 (in 4) | |
| ID | Inside diameter, mm (in) | |
| k | Spring rate, N/mm (lb/in) or N mm/r (lb in/r) |
| K | Design constant | |
| K w | Stress correction factor for helical springs | |
| L | Length, mm (in) | |
| L f | Free length, mm (in) | |
| L s | Length at solid, mm (in) | |
| M | Moment or torque, N mm (lb in) | |
| n | Frequency, Hz | |
| N a | Number of active coils or waves | |
| N t | Total number of coils | |
| OD | Outside diameter, mm (in) | |
| P | Load, N (lbf) | |
| r | Radius, mm (in) | |
| S | Stress, MPa (psi) | |
| TS | Tensile strength, MPa (psi) | |
| t | Thickness, mm (in) | |
| YS | Yield strength, MPa (psi) | |
| ? | Density, g/cm 3 (lb/in 3) | |
| ? | Angular deflection, expressed in number of revolutions | |
| | Poisson s ratio |
[ ] The...
