Which joint configuration is described as a single bevel groove with a 45-degree groove angle with metal backing to achieve complete joint penetration?

Which joint configuration is described as a single bevel groove with a 45-degree groove angle with metal backing to achieve complete joint penetration?

• A. Double vee groove with backgouge to sound metal after the other side was welded
• B. Single bevel groove with a 45-degree groove angle with metal backing
• C. Square groove with backing
• D. U-groove with backing

Answer: (B)

Groove geometry and backing determine whether a weld can reach complete joint penetration from one side. A single bevel groove with a 45-degree angle creates a larger root opening, giving the molten metal a clearer path to fuse all the way through the thickness. When metal backing is used, it provides a solid substrate behind the root, supporting the weld and preventing burn-through, so the root can be fused properly from the front. This combination makes it possible to achieve complete penetration with a single-side weld. Other groove types either lack sufficient root opening, require back gouging or welding from both sides, or rely on more complex multi-pass techniques to reach full penetration.

Groove geometry and backing determine whether a weld can reach complete joint penetration from one side. A single bevel groove with a 45-degree angle creates a larger root opening, giving the molten metal a clearer path to fuse all the way through the thickness. When metal backing is used, it provides a solid substrate behind the root, supporting the weld and preventing burn-through, so the root can be fused properly from the front. This combination makes it possible to achieve complete penetration with a single-side weld. Other groove types either lack sufficient root opening, require back gouging or welding from both sides, or rely on more complex multi-pass techniques to reach full penetration.