| $B_A$ | coefficient $ B_A $ | $\mathrm{}$ |
| $B_B$ | coefficient $ B_B $ | $\mathrm{}$ |
| $B_T$ | coefficient $ B_T $ | $\mathrm{}$ |
| $B_{1A-hub}$ | coefficient $ B_{1A-hub} $ | $\mathrm{}$ |
| $B_{1A-socket}$ | coefficient $ B_{1A-socket} $ | $\mathrm{}$ |
| $B_{1A}$ | coefficient $ B_{1A} $ | $\mathrm{}$ |
| $B_{1B-hub}$ | coefficient $ B_{1B-hub} $ | $\mathrm{}$ |
| $B_{1B}$ | coefficient $ B_{1B} $ | $\mathrm{}$ |
| $B_{1T-hub}$ | coefficient $ B_{1T-hub} $ | $\mathrm{}$ |
| $B_{1T}$ | coefficient $ B_{1T} $ | $\mathrm{}$ |
| $B_{2A-hub}$ | coefficient $ B_{2A-hub} $ | $\mathrm{}$ |
| $B_{2A-socket}$ | coefficient $ B_{2A-socket} $ | $\mathrm{}$ |
| $B_{2A}$ | coefficient $ B_{2A} $ | $\mathrm{}$ |
| $B_{2B-hub}$ | coefficient $ B_{2B-hub} $ | $\mathrm{}$ |
| $B_{2B}$ | coefficient $ B_{2B} $ | $\mathrm{}$ |
| $B_{2T-hub}$ | coefficient $ B_{2T-hub} $ | $\mathrm{}$ |
| $B_{2T}$ | coefficient $ B_{2T} $ | $\mathrm{}$ |
| $B_{3A-hub}$ | coefficient $ B_{3A-hub} $ | $\mathrm{}$ |
| $B_{3A-socket}$ | coefficient $ B_{3A-socket} $ | $\mathrm{}$ |
| $B_{3A}$ | coefficient $ B_{3A} $ | $\mathrm{}$ |
| $B_{3B-hub}$ | coefficient $ B_{3B-hub} $ | $\mathrm{}$ |
| $B_{3B}$ | coefficient $ B_{3B} $ | $\mathrm{}$ |
| $B_{3T-hub}$ | coefficient $ B_{3T-hub} $ | $\mathrm{}$ |
| $B_{3T}$ | coefficient $ B_{3T} $ | $\mathrm{}$ |
| $B_{4A}$ | coefficient $ B_{4A} $ | $\mathrm{}$ |
| $B_{4B-hub}$ | coefficient $ B_{4B-hub} $ | $\mathrm{}$ |
| $B_{4B}$ | coefficient $ B_{4B} $ | $\mathrm{}$ |
| $B_{4T-hub}$ | coefficient $ B_{4T-hub} $ | $\mathrm{}$ |
| $B_{4T}$ | coefficient $ B_{4T} $ | $\mathrm{}$ |
| $B_{A-clevis}$ | coefficient $ B_{A-clevis} $ | $\mathrm{}$ |
| $B_{A-hub}$ | coefficient $ B_{A-hub} $ | $\mathrm{}$ |
| $B_{A-rod}$ | coefficient $ B_{A-rod} $ | $\mathrm{}$ |
| $B_{A-socket}$ | coefficient $ B_{A-socket} $ | $\mathrm{}$ |
| $B_{B-hub}$ | coefficient $ B_{B-hub} $ | $\mathrm{}$ |
| $B_{T-hub}$ | coefficient $ B_{T-hub} $ | $\mathrm{}$ |
| $C_c$ | coefficient according to load | $\mathrm{ }$ |
| $C_{D_0}$ | dimensional characteristics of the connection on diameter $ D_0 $ | $\mathrm{ }$ |
| $C_{D}$ | dimensional characteristics of the connection on diameter $ D $ | $\mathrm{ }$ |
| $C_{j-trunnion-clevis}$ | coefficient of joint for trunnion and clevis | $\mathrm{ }$ |
| $C_{j-trunnion-rod}$ | coefficient of joint for trunnion and rod | $\mathrm{ }$ |
| $D$ | diameter of the shaft | $\mathrm{mm}$ |
| $D$ | diameter $ D $ | $\mathrm{mm}$ |
| $D_0$ | inner diameter of the hollow shaft | $\mathrm{mm}$ |
| $D_1$ | diameter $ D_1 $ | $\mathrm{mm}$ |
| $D_h$ | diameter of the hub | $\mathrm{mm}$ |
| $E$ | Young's modulus | $\mathrm{MPa}$ |
| $E_{hub}$ | Young's modulus for hub | $\mathrm{MPa}$ |
| $E_{shaft}$ | Young's modulus for shaft | $\mathrm{MPa}$ |
| $F$ | force | $\mathrm{kN}$ |
| $F_A$ | axial force | $\mathrm{kN}$ |
| $F_R$ | radial force | $\mathrm{kN}$ |
| $M_B$ | bending moment | $\mathrm{Nm}$ |
| $M_T$ | twisting moment | $\mathrm{Nm}$ |
| $P_B$ | bearing stress | $\mathrm{MPa}$ |
| $P_{B-cotter-socket}$ | bearing stress in the cotter and socket | $\mathrm{MPa}$ |
| $P_{B-cotter-spigot}$ | bearing stress in the cotter and spigot | $\mathrm{MPa}$ |
| $P_{B-key-hub}$ | bearing stress in the key and hub | $\mathrm{MPa}$ |
| $P_{B-key-shaft}$ | bearing stress in the key and shaft | $\mathrm{MPa}$ |
| $P_{B-pin-hub}$ | bearing stress in the pin and hub | $\mathrm{MPa}$ |
| $P_{B-pin-shaft}$ | bearing stress in the pin and shaft | $\mathrm{MPa}$ |
| $P_{B-trunnion-clevis}$ | bearing stress in the trunnion and clevis | $\mathrm{MPa}$ |
| $P_{B-trunnion-rod}$ | bearing stress in the trunnion and rod | $\mathrm{MPa}$ |
| $P_{all-B-clevis}$ | allowable bearing stress the clevis | $\mathrm{MPa}$ |
| $P_{all-B-cotter}$ | allowable bearing stress the cotter | $\mathrm{MPa}$ |
| $P_{all-B-hub}$ | allowable bearing stress the hub | $\mathrm{MPa}$ |
| $P_{all-B-key}$ | allowable bearing stress the key | $\mathrm{MPa}$ |
| $P_{all-B-pin}$ | allowable bearing stress the pin | $\mathrm{MPa}$ |
| $P_{all-B-rod}$ | allowable bearing stress the rod | $\mathrm{MPa}$ |
| $P_{all-B-shaft}$ | allowable bearing stress the shaft | $\mathrm{MPa}$ |
| $P_{all-B-socket}$ | allowable bearing stress the socket | $\mathrm{MPa}$ |
| $P_{all-B-spigot}$ | allowable bearing stress the spigot | $\mathrm{MPa}$ |
| $P_{all-B-trunnion}$ | allowable bearing stress the trunnion | $\mathrm{MPa}$ |
| $S_F$ | safety factor | $\mathrm{ }$ |
| $S_s$ | coefficient of max. stress increase | $\mathrm{ }$ |
| $S_{y-clevis}$ | the minimum yield strength of the clevis | $\mathrm{MPa}$ |
| $S_{y-cotter}$ | the minimum yield strength of the cotter | $\mathrm{MPa}$ |
| $S_{y-hub}$ | the minimum yield strength of the hub | $\mathrm{MPa}$ |
| $S_{y-key}$ | the minimum yield strength of the key | $\mathrm{MPa}$ |
| $S_{y-pin}$ | the minimum yield strength of the pin | $\mathrm{MPa}$ |
| $S_{y-rod}$ | the minimum yield strength of the rod | $\mathrm{MPa}$ |
| $S_{y-shaft}$ | the minimum yield strength of the shaft | $\mathrm{MPa}$ |
| $S_{y-socket}$ | the minimum yield strength of the socket | $\mathrm{MPa}$ |
| $S_{y-spigot}$ | the minimum yield strength of the spigot | $\mathrm{MPa}$ |
| $S_{y-trunnion}$ | the minimum yield strength of the trunnion | $\mathrm{MPa}$ |
| $T_a$ | ambient temperature | $\mathrm{°C}$ |
| $T_{hub}$ | temperature for hub | $\mathrm{°C}$ |
| $T_{shaft}$ | temperature for shaft | $\mathrm{°C}$ |
| $a$ | thickness the rod | $\mathrm{mm}$ |
| $a$ | length square head with load | $\mathrm{mm}$ |
| $a_1$ | length square head without load | $\mathrm{mm}$ |
| $a_c$ | assembly clearance | $\mathrm{mm}$ |
| $b$ | thickness the clevis | $\mathrm{mm}$ |
| $b$ | distance of the resultant of the pressure | $\mathrm{mm}$ |
| $b$ | width key | $\mathrm{mm}$ |
| $d$ | diameter of the pin | $\mathrm{mm}$ |
| $d$ | trunnion diameter | $\mathrm{mm}$ |
| $d$ | diameter $ d $ | $\mathrm{mm}$ |
| $d$ | spigot diameter | $\mathrm{mm}$ |
| $d_3$ | basic smaller diameter of external thread | $\mathrm{mm}$ |
| $d_8$ | diameter square head | $\mathrm{mm}$ |
| $d_9$ | free diameter | $\mathrm{mm}$ |
| $h$ | height key | $\mathrm{mm}$ |
| $h_1$ | length the rod | $\mathrm{mm}$ |
| $h_1$ | length the spigot | $\mathrm{mm}$ |
| $h_2$ | length the clevis | $\mathrm{mm}$ |
| $h_2$ | length the socket | $\mathrm{mm}$ |
| $h_h$ | the height of the key in the hub | $\mathrm{mm}$ |
| $h_s$ | the height of the key in the shaft | $\mathrm{mm}$ |
| $i$ | number of pins | $\mathrm{ }$ |
| $i$ | number of keys | $\mathrm{ }$ |
| $l$ | length pin | $\mathrm{mm}$ |
| $l$ | length square head in the hub | $\mathrm{mm}$ |
| $l$ | length key | $\mathrm{mm}$ |
| $l$ | bolt connection length | $\mathrm{mm}$ |
| $l$ | functional coupling length | $\mathrm{mm}$ |
| $l_1$ | width the rod | $\mathrm{mm}$ |
| $l_2$ | width the clevis | $\mathrm{mm}$ |
| $l_t$ | tolerance of key length | $\mathrm{mm}$ |
| $p_{max}$ | max. contact pressure | $\mathrm{MPa}$ |
| $p_{min}$ | min. contact pressure | $\mathrm{MPa}$ |
| $r$ | radius | $\mathrm{mm}$ |
| $r_1$ | max. rounding the key | $\mathrm{mm}$ |
| $r_2$ | groove rounding | $\mathrm{mm}$ |
| $s$ | gap | $\mathrm{mm}$ |
| $s$ | width square head | $\mathrm{mm}$ |
| $s$ | thickness the cotter | $\mathrm{mm}$ |
| $t$ | width between pins | $\mathrm{mm}$ |
| $t$ | depth in the shaft | $\mathrm{mm}$ |
| $t_1$ | depth in the hub | $\mathrm{mm}$ |
| $t_t$ | tolerance of the groove height in the shaft | $\mathrm{mm}$ |
| $t_{1t}$ | tolerance of the groove height in the hub | $\mathrm{mm}$ |
| $v$ | width the cotter | $\mathrm{mm}$ |
| $Δ_{max}$ | max. Interference | $\mathrm{mm}$ |
| $Δ_{min}$ | min. Interference | $\mathrm{mm}$ |
| $α$ | angle between pins | $\mathrm{rad}$ |
| $α_{hub}$ | coefficient of thermal expansion for hub | $\mathrm{K^{-1}}$ |
| $α_{shaft}$ | coefficient of thermal expansion for shaft | $\mathrm{K^{-1}}$ |
| $μ$ | friction coefficient | $\mathrm{ }$ |
| $ν_{hub}$ | Poisson's ratio for hub | $\mathrm{ }$ |
| $ν_{shaft}$ | Poisson's ratio for shaft | $\mathrm{ }$ |
| $σ_{A-clevis}$ | axial stress in the clevis | $\mathrm{MPa}$ |
| $σ_{A-hub}$ | axial stress in the hub | $\mathrm{MPa}$ |
| $σ_{A-rod}$ | axial stress in the rod | $\mathrm{MPa}$ |
| $σ_{A-shaft}$ | axial stress in the shaft | $\mathrm{MPa}$ |
| $σ_{A-socket}$ | axial stress in the socket | $\mathrm{MPa}$ |
| $σ_{A-spigot}$ | axial stress in the spigot | $\mathrm{MPa}$ |
| $σ_{B-cotter}$ | bending stress in the cotter | $\mathrm{MPa}$ |
| $σ_{B-hub}$ | bending stress in the hub | $\mathrm{MPa}$ |
| $σ_{B-shaft-hub}$ | bending stress in the weakened part of the shaft-hub | $\mathrm{MPa}$ |
| $σ_{B-shaft}$ | bending stress in the shaft | $\mathrm{MPa}$ |
| $σ_{B-trunnion}$ | bending stress in the trunnion | $\mathrm{MPa}$ |
| $σ_{R-hub-D}$ | radial stress in the hub on diameter $ D $ | $\mathrm{MPa}$ |
| $σ_{R-shaft-D_0}$ | radial stress in the shaft on diameter $ D_0 $ | $\mathrm{MPa}$ |
| $σ_{R-shaft-D}$ | radial stress in the shaft on diameter $ D $ | $\mathrm{MPa}$ |
| $σ_{T-hub-D}$ | tangential stress in the hub on diameter $ D $ | $\mathrm{MPa}$ |
| $σ_{T-shaft-D_0}$ | tangential stress in the shaft on diameter $ D_0 $ | $\mathrm{MPa}$ |
| $σ_{T-shaft-D}$ | tangential stress in the shaft on diameter $ D $ | $\mathrm{MPa}$ |
| $σ_{all-A-clevis}$ | allowable axial stress the clevis | $\mathrm{MPa}$ |
| $σ_{all-A-hub}$ | allowable axial stress the hub | $\mathrm{MPa}$ |
| $σ_{all-A-rod}$ | allowable axial stress the rod | $\mathrm{MPa}$ |
| $σ_{all-A-shaft}$ | allowable axial stress the shaft | $\mathrm{MPa}$ |
| $σ_{all-A-socket}$ | allowable axial stress the socket | $\mathrm{MPa}$ |
| $σ_{all-A-spigot}$ | allowable axial stress the spigot | $\mathrm{MPa}$ |
| $σ_{all-B-cotter}$ | allowable bending stress the cotter | $\mathrm{MPa}$ |
| $σ_{all-B-hub}$ | allowable bending stress the hub | $\mathrm{MPa}$ |
| $σ_{all-B-shaft}$ | allowable bending stress the shaft | $\mathrm{MPa}$ |
| $σ_{all-B-trunnion}$ | allowable bending stress the trunnion | $\mathrm{MPa}$ |
| $σ_{all-C-hub}$ | allowable combined stress the hub | $\mathrm{MPa}$ |
| $σ_{all-C-shaft}$ | allowable combined stress the shaft | $\mathrm{MPa}$ |
| $σ_{all-C-trunnion}$ | allowable combined stress the trunnion | $\mathrm{MPa}$ |
| $σ_{tresca-hub-D}$ | combined stress in the hub on diameter $ D $ | $\mathrm{MPa}$ |
| $σ_{tresca-hub}$ | combined stress in the hub | $\mathrm{MPa}$ |
| $σ_{tresca-shaft-D_0}$ | combined stress in the shaft on diameter $ D_0 $ | $\mathrm{MPa}$ |
| $σ_{tresca-shaft-D}$ | combined stress in the shaft on diameter $ D $ | $\mathrm{MPa}$ |
| $σ_{tresca-shaft}$ | combined stress in the shaft | $\mathrm{MPa}$ |
| $σ_{tresca-trunnion}$ | combined stress in the trunnion | $\mathrm{MPa}$ |
| $τ_{S-clevis}$ | shear stress in the clevis | $\mathrm{MPa}$ |
| $τ_{S-cotter}$ | shear stress in the cotter | $\mathrm{MPa}$ |
| $τ_{S-hub-D}$ | shear stress in the hub on diameter $ D $ | $\mathrm{MPa}$ |
| $τ_{S-hub}$ | shear stress in the hub | $\mathrm{MPa}$ |
| $τ_{S-key}$ | shear stress key | $\mathrm{MPa}$ |
| $τ_{S-pin}$ | shear stress in the pin | $\mathrm{MPa}$ |
| $τ_{S-rod}$ | shear stress in the rod | $\mathrm{MPa}$ |
| $τ_{S-shaft-D}$ | shear stress in the shaft on diameter $ D $ | $\mathrm{MPa}$ |
| $τ_{S-shaft-hub}$ | shear stress in the weakened part of the shaft-hub | $\mathrm{MPa}$ |
| $τ_{S-shaft}$ | shear stress in the shaft | $\mathrm{MPa}$ |
| $τ_{S-socket}$ | shear stress in the socket | $\mathrm{MPa}$ |
| $τ_{S-spigot}$ | shear stress in the spigot | $\mathrm{MPa}$ |
| $τ_{S-trunnion}$ | shear stress in the trunnion | $\mathrm{MPa}$ |
| $τ_{T-hub-D}$ | torsion stress in the hub on diameter $ D $ | $\mathrm{MPa}$ |
| $τ_{T-hub}$ | torsion stress in the hub | $\mathrm{MPa}$ |
| $τ_{T-shaft-D_0}$ | torsion stress in the shaft on diameter $ D_0 $ | $\mathrm{MPa}$ |
| $τ_{T-shaft-D}$ | torsion stress in the shaft on diameter $ D $ | $\mathrm{MPa}$ |
| $τ_{T-shaft}$ | torsion stress in the shaft | $\mathrm{MPa}$ |
| $τ_{all-S-clevis}$ | allowable shear stress the clevis | $\mathrm{MPa}$ |
| $τ_{all-S-cotter}$ | allowable shear stress the cotter | $\mathrm{MPa}$ |
| $τ_{all-S-hub}$ | allowable shear stress the hub | $\mathrm{MPa}$ |
| $τ_{all-S-key}$ | allowable shear stress the key | $\mathrm{MPa}$ |
| $τ_{all-S-pin}$ | allowable shear stress the pin | $\mathrm{MPa}$ |
| $τ_{all-S-rod}$ | allowable shear stress the rod | $\mathrm{MPa}$ |
| $τ_{all-S-shaft}$ | allowable shear stress the shaft | $\mathrm{MPa}$ |
| $τ_{all-S-socket}$ | allowable shear stress the socket | $\mathrm{MPa}$ |
| $τ_{all-S-spigot}$ | allowable shear stress the spigot | $\mathrm{MPa}$ |
| $τ_{all-S-trunnion}$ | allowable shear stress the trunnion | $\mathrm{MPa}$ |
| $ψ$ | angle of inclination of the tangent to the bending line | $\mathrm{rad}$ |
