If angles are prepared on both plates of the base metal before welding, what are these angles called?

When angles are prepared on both plates of the base metal prior to welding, these angles are referred to as groove angles. This preparation forms a specific configuration that allows for proper welding of the joint between the two pieces. In welding terminology, groove angles are designed to facilitate the creation of a strong joint by allowing weld material to fill the gap and create a solid bond between the surfaces being joined.

Groove angles are critical in defining the joint's shape and depth, which significantly affects the welding process, the amount of weld metal necessary, and, ultimately, the integrity of the weld.

The other terms listed have distinct meanings in welding. For instance, butt angles refer to the configuration of two pieces that are joined end-to-end, while weld angles and fillet angles pertain to different types of weld joint preparations and configurations. Understanding these specific terms helps ensure clarity in welding documentation and communication on the shop floor.