Which method is used to verify that throat thickness meets joint design requirements?

• A. Weld gauge or cross-section checks against the joint design
• B. Measuring the energy of the arc
• C. Listening to arc sound
• D. Visual color check only

Answer: (B)

Verifying throat thickness relies on direct measurement of the weld size because the throat is a geometric feature that determines strength and must match the design. Using a weld gauge or calipers to measure the throat at multiple points, or taking a cross-section and comparing the actual throat dimension to the drawing, provides an objective, quantitative check. This direct method is what quality control uses to confirm conformance with the joint design.

Other approaches don’t reliably assess the throat. Measuring arc energy reflects process conditions, not the finished geometry. Listening to the arc is subjective and cannot quantify throat size. Visual color checks assess surface appearance, not the actual throat thickness and can miss underfilled or undersized areas.