1. Welding Representation

2. Objectives Describe the various welding processes
Draw the common welding symbols
Dimension a welding drawing using standard ANSI welding notations

3. Objectives (cont.)
Identify and draw a fillet weld, groove weld, back weld, spot weld, seam weld, projection weld, and flash weld
Describe the use of welding symbols in CAD drawings

4. Welding Processes The principal methods of welding are: Gas welding
Arc welding
Resistance welding

5. Standard Symbols
Welding drawings are a special type of assembly drawing as weldments are composed of a number of separate pieces fastened together as a unit
Joints are all shown as they would appear before welding

6. Weldment Drawing

7. Welding Symbols
The items that can be specified in a welding symbol are:
Type of weld
Process
Depth of bevel, size or strength for some weld types
Groove weld size
Finishing designator
Contour

8. Welding Symbols Cont. Groove angle Root opening Length of weld
Number and pitch of welds
Whether the weld is to be field welded
All around indicator
Which side of the material is to be welded

9. Basic Welds and Symbols

10. Types of Welded Joints There are five basic types of welded joints:
Butt joint
Corner joint
T-joint
Lap joint
Edge joint

11. Types of Welded Joints

12. Types of Welds There are four types of arc and gas welds:
Back or backing weld
Fillet weld
Plug or slot weld
Groove weld

13. Types of Welds The four basic resistance welds are: Spot weld
Projection weld
Seam weld
Flash or upset weld

14. Welding Symbols The basic element of the symbol is the “bent” arrow
The arrow points to the joint where the weld is to be made
Attached to the reference line, or shank, is the symbol for the desired weld

15. Welding Symbols

16. Complete Welding Symbol

17. Fillet Welds
The usual fillet weld has equal legs

18. Groove Welds

19. Back or Backing Welds

20. Surface Welds
The surface weld symbol indicates a surface to be built up

21. Plug and Slot Welds

22. Spot Welds

23. Seam Welds

24. Projection Welds

25. Flash and Upset Welds
Flash and upset weld symbols have no arrow-side or other-side significance

26. Welding Applications
Welding is often cheaper when only one or a few identical parts are required
Welding is also suitable for large structures that are difficult or impossible to fabricate entirely in a shop

27. Welding Templates
Welding templates can simplify drawing welding symbols by hand
They have all the forms needed for drawing the arrow, weld symbols, and supplementary symbols

28. Computer Graphics
Welding symbol libraries available in CAD and allow for rapid application of accurate, uniform symbols that are in compliance with standards