List of symbols

Symbol Name of the symbol Unit
$ $trapezoidal thread$\mathrm{ }$
$ $type of strut mounting$\mathrm{ }$
$C_c$coefficient according to load$\mathrm{ }$
$C_t$power screw coefficient$\mathrm{ }$
$D_1$minor diameter for internal threads$\mathrm{mm}$
$D_4$major diameter for internal threads$\mathrm{mm}$
$E$Young's modulus$\mathrm{MPa}$
$F_A$axial force$\mathrm{N}$
$F_{max}$maximal (critical) force$\mathrm{N}$
$H_1$height of the overlapping$\mathrm{mm}$
$H_4$height of internal threads$\mathrm{mm}$
$I$second moment of area$\mathrm{mm^4}$
$L$strut length$\mathrm{mm}$
$M_T$twisting moment$\mathrm{Nm}$
$M_T$lifting torque$\mathrm{Nm}$
$P_{B-screw-nut}$bearing stress in the screw and nut$\mathrm{MPa}$
$P_{all-B-nut}$allowable bearing stress the nut$\mathrm{MPa}$
$P_{all-B-screw}$allowable bearing stress the screw$\mathrm{MPa}$
$R_{1max}$dimension $ R_{1max} $ $\mathrm{mm}$
$R_{2max}$dimension $ R_{2max} $ $\mathrm{mm}$
$S$profile area$\mathrm{mm^2}$
$S_F$safety factor$\mathrm{ }$
$S_{FB}$safety factor buckling$\mathrm{ }$
$S_{y-nut}$the minimum yield strength of the nut$\mathrm{MPa}$
$S_{y-screw}$the minimum yield strength of the screw$\mathrm{MPa}$
$a_c$clearance on the crest$\mathrm{mm}$
$c$extreme fiber distance$\mathrm{mm}$
$d$major diameter for external thread (nominal diameter)$\mathrm{mm}$
$d_2$pitch diameter for external threads$\mathrm{mm}$
$d_3$minor diameter for external threads$\mathrm{mm}$
$h_3$height of external threads$\mathrm{mm}$
$i$gyration radius$\mathrm{mm}$
$l$length nut$\mathrm{mm}$
$v$screw speed$\mathrm{m/s}$
$z$dimension $ z $ $\mathrm{mm}$
$β$coefficient for buckling$\mathrm{ }$
$μ$friction coefficient$\mathrm{ }$
$σ_{A-screw}$axial stress in the screw$\mathrm{MPa}$
$σ_{all-A-screw}$allowable axial stress the screw$\mathrm{MPa}$
$σ_{all-C-screw}$allowable combined stress the screw$\mathrm{MPa}$
$σ_{tresca-screw}$combined stress in the screw$\mathrm{MPa}$
$τ_{S-screw}$shear stress in the screw$\mathrm{MPa}$
$τ_{all-S-screw}$allowable shear stress the screw$\mathrm{MPa}$