In what scenario is it appropriate to use throat thickness for measurement?

Using throat thickness for measurement is pertinent in specific types of welds, particularly flare-groove welds. In the context of welding, throat thickness refers to the minimum distance from the root of the weld to the face of the weld, which significantly impacts the weld's strength and performance.

When evaluating flare-groove welds, the throat thickness is a critical measure because it directly influences the weld's capacity to withstand loads. This type of weld is often used where two parts are joined at an angle, and the design can involve either reinforcement (where extra material is added beyond the basic weld needed) or no reinforcement.

The choice stating that throat thickness is applicable for flare-groove welds or without reinforcement highlights the versatility of this measurement. It recognizes that, regardless of whether reinforcement is present, the throat thickness still serves as an important metric for assessing the weld's structural integrity. Thus, this option effectively encompasses scenarios where throat thickness is crucial, making it the most appropriate choice in the context of flare-groove welds.

In contrast, while throat thickness might be relevant for other types of welds, such as convex fillet welds, it may not always provide a complete understanding of those welds' geometry and performance,