Definitions
| A | Shaft cross section [mm2] | i | Number of ball circles |
| α | Coefficient of thermal expansion [1/°C] |
JIS | Japanese Industrial Standard |
| c | Lead compensation | k | Support coefficient (critical speed) |
| C0a | Static axial load capacity [N] | L10 | Nominal life 90% reliability [106 revolutions] |
| Ca | Dynamic axial load capacity [N] | ls | Unsupported shaft length [mm] |
| Caerf |
Required dynamic axial |
lu | Travel [mm] |
| Δlb/t | Axial elastic deformation due to external load Fi [µm] |
m | Support coefficient (buckling] |
| Δlb/t,pr |
Axial elastic deformation |
ni | Speed [rpm] |
| Δlp | Elongation of the shaft [mm] | nk | Critical speed [rpm] |
| ΔlT | Thermal expansion [mm] | nm | Equivalent Speed [1/min] |
| dN | Nominal diameter [mm] | nmax | Maximum Speed [rpm] |
| DN | DN value [mm/min] | P | Lead [mm] |
| Δt | Temperature increase [°C] | PB | Buckling load [N] |
| "E" | Tolerance of the cumulative lead error (JIS) |
Pi | Load capacity per ANSI [lbf] |
| E | Elasticity modulus [N/mm2] | qi | Time percentage [%] |
| ε | Elongation relative to length | Rb | Axial bearing rigidity [N/µm] |
| e0a | Mean lead deviation over entire travel lu |
Rnu,ar | Actual nut rigidity [N/µm] |
| e2π | Lead error in one revolution (JIS) | Rs | Shaft rigidity [N/µm] |
| e300 | Lead error in 300 mm (JIS) | Rt | Rigidity of ball screw [N/µm] |
| ep | Tolerance for the average lead deviation over entire travel lu |
T | Travel compensation (JIS) |
| esa | Actual lead deviation over entire travel lu |
Tpr | Preload torque |
| Fi | External load [N] | v2πa | Lead fluctuation in one revolution |
| Fi* | Modified external load [N] | v300a | Lead fluctuation in 300 mm |
| Fm | Dynamic equivalent load [N] | v300p | Tolerance of the lead fluctuation in 300 mm |
| Fm* | Modified dynamic equivalent load [N] |
vua | Lead deviation over entire travel lu |
| Fpr | Preload [N] | vup | Tolerance of the lead deviation over entire travel lu |
| FT | Tensioning force [N] |