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Module 9 of 10 240m 5 exam Qs

Weld Symbols and Drawing Interpretation

Reference lines, arrow side, other side, field welds, weld-all-around, and supplementary symbols.

  • Identify the components of a standard AWS weld symbol
  • Explain arrow side and other side placement conventions
  • Interpret supplementary symbols including field weld and weld-all-around

Lesson 1

Weld Symbol Basics and Reference Line

Weld Symbol Anatomy

The AWS weld symbol is a standardized graphical shorthand used on engineering drawings to specify exactly what type of weld is required, where it goes, its size, and any special requirements. Every weld symbol is built on a reference line - a horizontal line with an arrow pointing to the joint.

The reference line is the backbone of the symbol. Information placed below the reference line applies to the arrow side of the joint (the side the arrow points to). Information placed above the reference line applies to the other side of the joint.

Arrow
Points to the joint location
Reference Line
Horizontal line carrying all info
Tail
Optional - contains specifications, notes

Weld Type Symbols

The basic weld type is shown by a small symbol on the reference line:

  • Fillet weld - right triangle shape
  • V-groove - V shape
  • Bevel groove - half-V shape
  • U-groove - U shape
  • J-groove - J shape
  • Plug/slot weld - rectangle
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Exam Tip

The reference line is always horizontal. The arrow can point up or down. Remember: below the line = arrow side, above the line = other side.

Key Takeaway

Every weld symbol is built on a reference line with an arrow pointing to the joint. Information below the line = arrow side, above the line = other side. The weld type is shown by a standardized geometric symbol on the reference line.