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Plug and Slot Welds

bplc 4

Axial Force on Perpendicular Plug Weld formulas

\( \tau_b \;=\;   \dfrac{ P }{ 0.5 \cdot d^2 \cdot n  }     \)

\( \tau_p \;=\;   \dfrac{ P }{ 2.2 \cdot d \cdot t \cdot n  }     \)
Symbol English Metric
\( \tau_b \) (Greak symbol tau) = shear stress in weld base area \(lbf\;/\;in^2\)  \(Pa\) 
\( \tau_p \) (Greak symbol tau) = shear stress in weld peripheral area  \(lbf\;/\;in^2\) \(Pa\) 
\( d \) = diameter of plug weld \( in \) \( mm \)
\( n \) = number of welds \(dimensionless\) \(dimensionless\)  
\( t \) = plate thickness \( in \)   \( mm \)
\( P \) = total axial force  \(lbf\)  \(N\)

          

bplc 4

Axial Force on Bevel Plug Weld formulas

\( \tau_b \;=\;   \dfrac{ P }{ 0.8 \cdot d^2 \cdot n  }     \)

\( \tau_p \;=\;   \dfrac{ P }{ 3.1 \cdot d \cdot t \cdot n  }     \)
Symbol English Metric
\( \tau_b \) (Greak symbol tau) = shear stress in weld base area \(lbf\;/\;in^2\)  \(Pa\) 
 \( \tau_p \) (Greak symbol tau) = shear stress in weld peripheral area \(lbf\;/\;in^2\) \(Pa\)
 \( d \) = diameter of plug weld \( in \)   \( mm \)
 \( n \) = number of welds \(dimensionless\)    \(dimensionless\) 
 \( t \) = plate thickness \( in \)  \( mm \) 
 \( P \) = total axial force \(lbf\)   \(N\)

                 

bplc 4

Axial Force on Perpendicular Slot Weld formulas

\( \tau_b \;=\;   \dfrac{ P }{ 0.7 \cdot w \cdot L \cdot n  }     \)

\( \tau_p \;=\;   \dfrac{ P }{ 1.4 \cdot t \cdot L \cdot n  }     \)
Symbol English Metric
\( \tau_b \) (Greak symbol tau) = shear stress in weld base area \(lbf\;/\;in^2\)  \(Pa\) 
\( \tau_p \) (Greak symbol tau) = shear stress in weld peripheral area \(lbf\;/\;in^2\)  \(Pa\) 
\( L \) = length of welds \( in \)  \( mm \) 
\( n \) = number of welds  \(dimensionless\)   \(dimensionless\) 
\( t \) = plate thickness  \( in \) \( mm \) 
\( P \) = total axial force  \(lbf\) \(N\) 
\( w \) = width of weld \( in \)  \( mm \) 

              

bplc 4

Axial Force on Bevel Slot Weld formulas

\( \tau_b \;=\;   \dfrac{ P }{ w \cdot L \cdot n  }     \)

\( \tau_p \;=\;   \dfrac{ P }{ 2 \cdot t \cdot L \cdot n  }     \)
Symbol English Metric
\( \tau_b \) (Greak symbol tau) = shear stress in weld base area \(lbf\;/\;in^2\)  \(Pa\) 
\( \tau_p \) (Greak symbol tau) = shear stress in weld peripheral area \(lbf\;/\;in^2\)  \(Pa\) 
\( L \) = length of welds \( in \)   \( mm \)
\( n \) = number of welds  \(dimensionless\)  \(dimensionless\)  
\( t \) = plate thickness \( in \)  \( mm \) 
\( P \) = total axial force \(lbf\) \(N\)
\( w \) = width of weld \( in \)  \( mm \) 

 

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