What is the junction requirement for radiographs on vertical and horizontal welds?

• A. Only vertical joints need junction radiographs
• B. Only horizontal joints require junction radiographs
• C. Junctions of vertical and horizontal welds must be radiographed
• D. Junctions do not require any radiography

Answer: (C)

The requirement for junction radiographs on vertical and horizontal welds is based on ensuring the integrity and quality of the welds at their intersection points. Junctions of vertical and horizontal welds must be radiographed to detect any defects that could compromise the structural integrity of the tank. These junctions are critical areas where stresses and loads may be concentrated, and undetected flaws can lead to significant failures.

Radiography serves as a non-destructive testing method that allows for the evaluation of the internal structure of the welds, revealing issues such as voids, cracks, or incomplete fusion that may not be visible externally. By inspecting both vertical and horizontal weld junctions, manufacturers can ensure that the tank not only meets safety standards but also performs reliably in service.

The exclusion of radiographic requirements for either vertical or horizontal joints would potentially overlook critical vulnerabilities at the junctions where these two types of welds intersect, which is why comprehensive radiography of these junctions is essential for the overall safety and durability of welded tanks for oil storage.