What is described as a horizontal line proportion of a welding symbol?

The term associated with a horizontal line in a welding symbol is referred to as the welding reference line. This line serves as the foundation for the assembly of the welding symbol and is crucial for indicating where and how the weld should be made.

In a welding symbol, the reference line is horizontal because it provides a clear and consistent baseline from which other elements of the symbol are added, such as the type of weld, the size of the weld, and any additional specifications. Understanding the role of the welding reference line is vital for anyone interpreting or creating welding symbols, as it guides welders and inspectors in ensuring accurate and uniform welding practices.

The other terms, while related to welding, do not serve the same purpose as the welding reference line. For instance, the weld line refers specifically to the actual location of the weld on the workpiece, while the joint line signifies the interface between the two parts being joined. Finally, the symmetry line is a concept used in the context of symmetry in designs but does not directly relate to the standard components of a welding symbol.