TABLE OF CONTENTS | b | width of keyway, m (in) | |
| c | machine cost, $/m ($/in) (US dollars) | |
| D | diameter of shaft (also with subscripts), m (in) | |
| D i | inside diameter of hollow shaft, m (in) | |
| D o | outside diameter of hollow shaft, m (in) | |
| E | modulus of elasticity, GPa (Mpsi) | |
| F | axial load (tensile or compressive), kN (lbf) | |
| F' m | the static equivalent of cyclic load, (= F m F a), kN (lbf) | |
| G | modulus of rigidity, GPa (Mpsi) | |
| h | depth of keyway, m (in) | |
| k | radius of gyration, m (in) material cost (also with subscripts), $/kg | |
 | ratio of inner to outer diameter of hollow shaft | |
| K b | numerical combined shock and fatigue factor to be applied to computed bending moment | |
| K t | numerical combined shock and fatigue factor to be applied to computed twisting moment | |
| l | length, m (in) | |
| M b | bending moment, N m (lbf in) | |
| M t | twisting moment, Nm (lbf in) | |
| M t bm | static equivalent of cyclic bending moment M bm M ba, Nm(lbf in) | |
| M t tm | static equivalent of cyclic twisting moment M tm M ta, Nm(lbf in) | |
| p | power, kW (hp) | |
| n | speed, rpm; safety factor | |
| n' | speed, rps | |
| ? | specific weight of material, kN/m 3 (lbf/in) | |
| ? | stress (tensile or compressive) also with subscripts,... |
