If you refer to distances between welds along a flange-web junction I preferably would make them continuous, and if not, the closer the better. 30 cm would be my maximum between centers ... these webs are subject to compression where the lateral restraint is provided by the flanges through the web. Also subject to tension in fatigue, hence always, a fatigue analysis for the detail is required.
Thanks for your reply. However, I'm looking for minimum clearance between welds, in particular full penetration welds on plate structures. I'm concerned about welding guidelines or specifications where welds intersect on ship structures.
I've seen a couple of sheets of weld spacings at local shipyard and if not mistaken they came form the ABS(American Bureau of Ships). If possible check with the local jurisdiction that covers the ship, a marine surveyor or insurance company. In the US the ship would be the under the Coast Guard jurisdiction . They can point you in the right direction.
You appear to be concerned with the effect of the opposed welding residual tensile stresses on the narrow plate component between the welds. An "old rule-of-thumb" axiom defining the minimum distance between welds was the greater of 2" (50 mm)or 2 x thickness of the base plate.
