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American Welding Society Welding Symbol Chart
Contents
The American Welding Society (AWS) provides a comprehensive set of symbols for representing welds on engineering drawings. Below is a chart summarizing these symbols based on AWS standards:
| Welding Symbol | Description |
|---|---|
| Fillet Weld | A triangular weld that joins two surfaces at right angles. |
| Square Groove Weld | A weld with a square groove. |
| V-Groove Weld | A weld with a V-shaped groove. |
| Bevel Groove Weld | A weld with a bevel-shaped groove on one piece. |
| U-Groove Weld | A weld with a U-shaped groove. |
| J-Groove Weld | A weld with a J-shaped groove on one piece. |
| Flare-V Groove Weld | A weld with a flare V-groove, typically on curved surfaces. |
| Flare-Bevel Groove Weld | A weld with a flare bevel groove, typically on curved surfaces. |
| Plug Weld | A weld in a circular hole to join overlapping members. |
| Slot Weld | A weld in an elongated hole to join overlapping members. |
| Spot Weld | A weld made by electrical resistance at a single spot. |
| Seam Weld | A continuous weld made along a seam. |
| Backing (or Back) Weld | A weld applied to the reverse side of a joint. |
| Surfacing Weld | A weld used to apply a layer of metal on a surface. |
Additional Symbols and Modifiers
- Arrow Line: Points to the location of the weld.
- Reference Line: The baseline to which all symbols are attached.
- Tail: May include supplementary information about the weld process, filler material, etc.
- Weld All Around: A circle around the intersection of the reference line and arrow line, indicating that the weld is to be made all around the joint.
- Field Weld: A flag at the junction of the reference line and arrow line indicates that the weld is to be made in the field.
Basic Weld Symbols
Weld symbols are used on engineering drawings to indicate the type of weld, its size, and other pertinent information. Here are some of the basic weld symbols:
- Fillet Weld: A triangular weld symbol used to join two surfaces at approximately right angles to each other.
- Groove Weld: These welds are used to fill in the space between two members that are to be joined. Examples include square, bevel, V, U, and J-groove welds.
- Plug or Slot Weld: These are circular or elongated holes in one member of a joint that are filled with weld metal.
- Spot Weld: A weld made by the heat obtained from resistance to electric current flow through the workpieces held together under pressure.
- Seam Weld: A continuous weld made by moving the welding electrode along a seam to produce a continuous joint.
- Backing (or Back) Weld: Used to provide support to ensure complete penetration and prevent weld metal from seeping through the joint.
- Surfacing Weld: Used to apply a layer of metal to the surface of a workpiece, often for wear resistance.
ISO Standard for Welding Symbols
The ISO standard for welding symbols is ISO 2553. This standard provides guidelines for the representation of welded joints on drawings, ensuring uniformity in the presentation of welding symbols across different countries and industries.
AWS Code for Welding Symbols
The American Welding Society (AWS) code for welding symbols is found in AWS A2.4, “Standard Symbols for Welding, Brazing, and Nondestructive Examination.” This standard outlines the use of symbols to indicate welding requirements and is widely used in the United States and other countries.
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