Weld Visual Acceptance: Cracks, Undersize, and Undercut

The three things that decide it are kept separate, because they fail differently. A CRACK IS REJECTABLE WITHOUT DIMENSION and is reported first. No size, length or location tolerance applies to a crack, and the one that gets argued about is the crater crack at a stop, which is small, looks cosmetic, and is a crack. Nothing else in the examination is reached once one is found. UNDERSIZE IS TWO TESTS, NOT ONE. The code permits a limited amount of undersize over a limited length, and both have to be satisfied -- so a weld a sixteenth light over three inches of a twenty-inch run can be acceptable while the same sixteenth light over the whole twenty inches is not. Checking the amount and forgetting the length, or the reverse, accepts welds the code rejects. A uniformly small weld is a different defect from a local low spot and the code treats it that way. THE LIMITS THEMSELVES DEPEND ON THE LOADING. Undercut allowances tighten and porosity criteria change between statically and cyclically loaded connections, so the same weld can pass as static and fail as cyclic. An inspector has to know which a connection is before opening a table, and on a structure carrying both kinds of member the criteria change from member to member -- which is why the limits are entered here rather than built in. Reproducing a code's acceptance table would also go stale between editions and would be wrong for every code but the one chosen. This screens entered measurements against entered limits. It does not reproduce any code's acceptance table, determine which criteria apply to a connection, cover the full range of visual acceptance items (reinforcement, convexity, overlap, weld profile, arc strikes, spatter, fusion at the toes, or the fit-up and root conditions that decide many of them), address weld size measurement technique or gauge selection, evaluate porosity or slag distribution, qualify a welder or a procedure, or replace the examination itself. AWS D1.1, AWS D1.5, ASME Section IX or the applicable code and the contract documents, and the certified welding inspector, govern.

a crack is rejectable WITHOUT regard to size; undersize is two independent tests -- the amount against a permitted allowance and the length against a permitted fraction of the weld, both of which must pass; undercut is compared against a limit that differs between statically and cyclically loaded connections.

Weld visual acceptance as AWS D1.1 and equivalent codes structure it. Every limit is ENTERED from the applicable code and edition, because an acceptance table reproduced here would go stale between editions and be wrong for every code but the one chosen.

Comparisons against entered limits; no code table is reproduced.

Estimate. AHJ and licensed professional govern.

Field names used by the API: nominal_leg_in, measured_leg_in, undersize_length_in, weld_length_in, allowed_undersize_in, allowed_undersize_fraction, measured_undercut_in, allowed_undercut_in, crack_present, undersize_in, undersize_length_fraction, allowed_undersize_length_in, undercut_margin_in

• Limits are entered per code and edition no acceptance table is reproducedAWS D1.1 or the applicable code
• Loading must be known first static and cyclic criteria differthe contract documents
• A subset of visual items reinforcement, convexity, overlap, profile and arc strikes are not coveredthe full visual examination