Types of welding joints
The fetched Omni welding page covers lap and butt joints. For lap joints, it considers single and double transverse fillet welds, parallel welds, and combined U-shaped welds. For butt joints, it covers single-sided and double-sided welds.
Weld strength calculation
Single transverse: P = 0.707 x s x sigma_t x l
Double transverse: P = 2 x 0.707 x s x sigma_t x l
Double parallel: P = 2 x 0.707 x s x tau x l
Combined: P = 0.707 x s x sigma_t x l1 + 2 x 0.707 x s x tau x l2
Single butt: P = t x l x sigma_t
Double butt: P = (t1 + t2) x l x sigma_t
Source example
Omni's example uses a single transverse fillet weld with 5 mm size, 100 mm weld length, and 70 MPa allowable tensile stress, giving a strength of 24.745 kN. Those values are loaded by default.