1. Engineering Drawing and Design Chapter 18 Welding Drawings
Seventh Edition
Chapter 18
Welding Drawings

2. 18-1 Designing for welding
The primary importance of welding is to unite various pieces of metal so that they will operate as a unit structure to support the loads to be carried
Welding processes include arc welding, gas welding, and resistance welding (40 total processes exist)

3. Gas & Arc Welding
Most common form is oxyacetylene welding gets heat from the burning of flammable gases. It is slow compared to other modern welding methods so is used primarily for repair & maintenance
Arc welding is the major industrial welding process-heat is generated by an electric arc struck between a welding electrode, or rod, and the workpiece. The arc is hot and melting and solidification of the weld metal occurs rapidly.

4. Resistance welding Widely used especially for mass production work
Heat is created from resistance losses as a high amperage current is sent across a joint between 2 mating surfaces

5. Plug welding
A plug weld refers to joining two pieces by welding through a hold in one of the pieces*

6. WELDING DRAWINGS BASIC WELDING JOINTS J-GROOVE FLARE BEVEL GROOVE SPOT
PROJECTION
SEAM
FILLET
PLUG
SLOT
SQUARE GROOVE
BEVEL GROOVE
APPLICABLE WELDS
TYPE OF JOINT
BASIC WELDING JOINTS

7. WELDING DRAWINGS BASIC WELDING JOINTS J-GROOVE FLARE V-GROOVE
FLARE BEVEL GROOVE
EDGE FLANGE
SQUARE GROOVE
V-GROOVE
BEVEL GROOVE
U-GROOVE
APPLICABLE WELDS
TYPE OF JOINT
BASIC WELDING JOINTS

8. WELDING DRAWINGS BASIC WELDING JOINTS FLARE V-GROOVE
FLARE BEVEL GROOVE
EDGE FLANGE
CORNER FLANGE
SPOT
PROJECTION
SEAM
FILLET
SQUARE GROOVE
V-GROOVE
BEVEL GROOVE
U-GROOVE
J-GROOVE
APPLICABLE WELDS
TYPE OF JOINT
BASIC WELDING JOINTS

9. WELDING DRAWINGS BASIC WELDING JOINTS J-GROOVE FLARE BEVEL GROOVE SPOT
PROJECTION
SEAM
FILLET
PLUG
SLOT
BEVEL GROOVE
APPLICABLE WELDS
TYPE OF JOINT
BASIC WELDING JOINTS

10. WELDING DRAWINGS BASIC WELDING JOINTS EDGE FLANGE CORNER FLANGE SPOT
PROJECTION
SEAM
EDGE
PLUG
SLOT
SQUARE GROOVE
BEVEL GROOVE
V-GROOVE
U-GROOVE
J-GROOVE
APPLICABLE WELDS
TYPE OF JOINT
BASIC WELDING JOINTS

11. The difference between Weld symbol & Welding symbol…*
Weld symbol indicates the type of weld
Welding symbol is a method of representing the weld on drawings. It includes supplementary information & consists of the following 8 elements.
Reference line
Arrow
Basic weld symbol
Dimension and other data
Supplementary symbols
Finish symbols
Tail
Specification, process or other reference

12. 18-2 Welding Symbols
Tail of the symbol designates the welding specification, procedures, or other information used to make the weld*
Letters designate weld & cutting processes (Table 18-3)
A-2, SAW, process specifications all can be found in the weld tail symbol*

13. Location significance of Arrow*
Arrow side- for fillet, groove, flanged weld symbols the arrow connecting the welding symbol reference line to one side of the joint
Other side – the side opposite the arrow side
Both sides

14. WELDING DRAWINGS
WELD TERMINOLOGY

15. Weld terminology Leg Face Throat Groove radius
Root opening (groove weld) is the space between the pieces before welding*
Root face
Groove angle

16. WELDING DRAWINGS
WELD TERMINOLOGY

17. WELDING DRAWINGS
WELD TERMINOLOGY

18. WELDING DRAWINGS
WELDING SYMBOLS

19. WELDING DRAWINGS
WELD TERMINOLOGY

20. WELDING DRAWINGS
WELD TERMINOLOGY

21. WELDING DRAWINGS
SINGLE
DOUBLE
FILLET
FILLET AND GROOVE WELDS

22. WELDING DRAWINGS WELDING DRAWINGS
SINGLE
DOUBLE
SQUARE
FILLET AND GROOVE WELDS

23. WELDING DRAWINGS
SINGLE
DOUBLE
BEVEL
GROOVE
FILLET AND GROOVE WELDS

24. WELDING DRAWINGS
SINGLE
DOUBLE
V-GROOVE
FILLET AND GROOVE WELDS

25. WELDING DRAWINGS
SINGLE
DOUBLE
J-GROOVE
FILLET AND GROOVE WELDS

26. WELDING DRAWINGS
SINGLE
DOUBLE
U-GROOVE
FILLET AND GROOVE WELDS

27. WELDING DRAWINGS SINGLE DOUBLE FLARE- BEVEL GROOVE
FILLET AND GROOVE WELDS

28. WELDING DRAWINGS
SINGLE
DOUBLE
FLARE-V
GROOVE
FILLET AND GROOVE WELDS

29. Orientation of specific weld symbols
Fillet, bevel-groove, J-groove, flare-groove, corner-flange welds symbols are drawn with the perpendicular leg always to the left
Break in arrow-when only 1 member of a joint is to be prepared, the arrow has a break and points toward that member figure 18-9

30. Location of weld symbol wrt joint*
Welds on the arrow side of the joint are shown by placing the weld symbol below the reference line
Welds on the other side of the joint are shown by placing the weld symbol above the reference line
Welds on both sides of the joint are shown by placing the weld symbol on both sides of the reference line

31. Field welds & All around welds
Weld extending completely around a joint is indicated by a weld-all-around symbol placed at the intersection of the reference line and the arrow
Figure 18-11
Not required for welds extending around the circumference of a pipe
Not made in the shop or at the place of initial construction
Small black flag symbol* is placed above and at right angles to the reference line
Figure 18-10

32. More about weld symbols….
Combined weld symbols figure 18-12
Contours obtained by welding
Flat
Convex
Concave
Finishing of welds
grinding(G)
Chipping(C)
Machining (M)
Rolling (R)
Hammering (H)

33. Last slide on weld symbols
Multiple reference lines indicate a sequence of operations to be done at a single location*
Tail of welding symbol*
Welding process
Tables 18-3,18-4
Omitted when no references are required

34. WELDING DRAWINGS
COMBINED WELDING SYMBOLS

35. Design of welded joints
The size of the weld should always be designed with reference to the size of the thinner member
Fillets welds are cheaper and easier to apply than groove
Full-strength fillet welds joining 2 different thicknesses of material should be sized using a table of recommended full strength weld sizes based on the thinner plate*

36. WELDING DRAWINGS
FINISHING OF WELDS

37. 18-3 Fillet Welds & weld symbol (WS)
Dimensions of fillet welds are shown on the same side of the reference line as the WS & to the left
Specify dimensions of fillet welds on both sides of a joint
Vertical part of fillet weld symbol always on left*
If using a general note giving fillet weld dimensions, dimensions may be left off WS
If dimensions differ from general note show them on WS
Length of weld shown to right of WS

38. More on fillet welds…
Staggered intermittent fillet welds are designated in the weld symbol by staggering where the weld symbol appears on the reference line (p.652*)

39. Size of fillet welds Table 8-5 p.651
A practical method to size fillet welds is to design the weld for the thinner plate, making it sufficient to carry 1/3 to ½ the carrying capacity of the plate.

40. COMPARISON OF A CAST SHAFT SUPPORT WITH A WELDED STEEL SHAFT SUPPORT
WELDING DRAWINGS
COMPARISON OF A CAST SHAFT SUPPORT WITH A WELDED STEEL SHAFT SUPPORT

41. 18-4 Groove Weld symbol
Dimensions of groove weld are shown on the same side of the reference line as the welding symbol
When both sides of a double-groove weld have the same (or different) dimension, both sides are dimensioned, however the root opening needs to appear only once
When a general note governs dimensions of groove welds, groove welds need not be dimensioned on the weld symbol

42. Back and Backing welds
Back or backing weld symbols are used to indicate bead-type back or backing welds of singe-groove welds
The back weld is made after the groove weld
The backing weld is made before the groove weld

43. WELDING DRAWINGS
APPLICATION OF BACK AND BACKING WELD SYMBOLS

44. 18-5 Other basic welds
Plug
Slot
Spot
Seam
Surface
Flanged
Stud

45. OTHER BASIC WELDING SYMBOLS AND THEIR LOCATION SIGNIFICANCE
WELDING DRAWINGS
OTHER BASIC WELDING SYMBOLS AND THEIR LOCATION SIGNIFICANCE