Fabrication Technology

A: A works because acceptance starts with what’s physically there: size and continuity against the drawing before you stress it. B feels disciplined, but UT on a small fillet without confirming nominal size is chasing precision before relevance. C mimics structural test logic, yet proof loading before basic dimensional acceptance is backwards and risky. D leans on paperwork faith; without a weld map or datasheets, that assumption is exactly how undersized welds sneak through.

A: A follows the chain: 220×24 ≈ 5.3 kW, divided by 5 mm/s gives about 1 kJ/mm before efficiency factors. B ignores arc efficiency and jumps a decade high. C remembers efficiency but overcorrects by an order, confusing percentage loss with total scale. D drags in furnace intuition, which operates on entirely different time and mass scales.

A: A matches the symptom directionality: last-pass bias points to sequence-driven residual stress. B sounds metallurgical, but galvanic effects don’t drive macroscopic bowing. C would hit strength and hardness more than geometry. D explains movement after unclamping, yet the distortion appearing post–stress relief, not immediately, breaks that line of reasoning.

A: A directly measures flatness with the tools at hand and ties to the GD&T intent. B confuses parallelism and thickness with flatness. C mixes functional testing with acceptance, masking a geometric nonconformance. D trusts process capability without evidence, a gap DFMEA flags immediately.