The American Welding Society (AWS) has developed a standard system A2.4 welding symbols, which is recognized and widely used worldwide. This standard is designed by a graphic display performance and type of solder joint in a simpler way than the written representation of it. In the assembly or manufacture of metal structures, the welder is usually guided by a plane provided by the designer or engineer showing welding, in detail, how to perform this structure.

In terms not only shows where to weld, but also specifies the type of joint, as well as the size and shape of the laces.
Welding symbols are a language of abstract and concrete. Their use would save time and money, and serves to ensure the objectivity of the work. It is desirable that the symbols used belong to a universal language, which is why symbols are used that have been standardized by the AWS or the Organization International Standard, together with the European Committee for Standardization (ISO / EN).

If it comes to making a good study about welding symbols, it is good to bear in mind the following points:
1. Introduction.
2. Development. Types of welded joints.
3. Symbolization system in welding, as defined in the ANSI / AWS A2.4-XX

• Graphic representation of the type of chamfer or bevel on the board.
• General comments on the graphical representation of the types of board.
• Dimensions of the welds.
• Graphic representation of the bevel and depth of penetration.
• Graphical representation of fillet welds.
• Determination of the size of the fillet welds.
• Examples of use of welding symbols described to this point.
• Symbols in discontinuous welds.
• Combination of symbols.
• Examples of symbols for indication of the dimensions in welding.
• Examples of indications of the depth of chamfer and penetration.
• Use of additional symbols.
• Graphic representation of the rest of the symbols used in welding.

4. Symbolization system applied to non destructive testing.

• Codes used to identify different END
• Examples of use of symbolism in NDT