Comparative stress for all types of plug and spot welds
where:
| τ Z | shear stress in the weld base area [MPa, psi] | |
| τ 0 | shear stress in the weld peripheral area [MPa, psi] | |
| α | conversion factor of weld joint [-] | 
Plug weld - perpendicular

Shear stress in the weld base area
Shear stress in the weld peripheral area
where:
| F | acting force [N, lb] | |
| d | diameter of plug weld [mm, in] | |
| i | number of welds [-] | |
| s | plate thickness [mm, in] | 
Plug weld - with bevel

Shear stress in the weld base area
Shear stress in the weld peripheral area
where:
| F | acting force [N, lb] | |
| d | diameter of plug weld [mm, in] | |
| i | number of welds [-] | |
| s | plate thickness [mm, in] | 
Groove weld - perpendicular

Shear stress in the weld base area
Shear stress in the weld peripheral area
where:
| F | acting force [N, lb] | |
| b | groove weld width [mm, in] | |
| L | groove weld length [mm, in] | |
| i | number of welds [-] | |
| s | plate thickness [mm, in] | 
Groove weld - with bevel

Shear stress in the weld base area
Shear stress in the weld peripheral area
Meaning of used variables:
| F | acting force [N, lb] | 
| d | diameter of plug weld [mm, in] | 
| b | groove weld width [mm, in] | 
| L | groove weld length [mm, in] | 
| i | number of welds [-] | 
| s | plate thickness [mm, in] | 
| τ Z | shear stress in the weld base area [MPa, psi] | 
| τ 0 | shear stress in the weld peripheral area [MPa, psi] | 
| α | conversion factor of weld joint [-] |