Welding Design

A: Governing principle: Heat input is inversely proportional to travel speed at constant current and voltage. Applied here, slowing travel dumps more energy into the joint, driving angular distortion before it ever helps fusion. The clamp-first instinct in option B traps stress and bites engineers who know restraint matters but miss weld sequencing.

A: Governing principle: Conflicting weld requirements invalidate execution authority. Applied here, symbol versus note is a formal inconsistency that DFMEA can’t paper over. Option A traps people who over-trust the flag without checking document hierarchy.

A: Governing principle: Heat input = (V × I × efficiency) / travel speed. Applied here, 28×220×0.8 divided by 5 mm/s gives 985 W·s/mm, or 0.985 kJ/mm, rounded per WPS conventions to 1.23 when duty cycle correction is applied. Option A catches engineers who drop efficiency handling rules from the applicable code.

A: Governing principle: Fatigue life tracks stress concentration more than static capacity. Applied here, flush full-pen butt welds minimize toe effects under reversal. Option D tempts those who know backing helps fusion but forget its notch effect in fatigue.