welding joint design and welding symbols. after completing this chapter, you will be able to: ◦...
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Welding Joint Design andWelding Symbols
After completing this chapter, you will be able to:◦Sketch the five basic welding joints◦Explain the factors that must be considered when
choosing a weld joint design◦Discuss the factors to consider when selecting a weld
joint design◦ List and explain the information that can be included on a
welding symbol◦Sketch a welding symbol and identify the components
Welding Joint Design & Welding Symbols – Chapter #5
Refers to the way pieces of metal are put together or aligned with each other
◦ The five (5) basic weld joint designs are:
Welding Joint Design & Welding Symbols – Chapter #5
Butt Joint
Lap Joint
Corner Joint
Tee Joint
Edge Joint
Name five basic weld joints that may be found in a weldment.
Welding Joint Design & Welding Symbols – Chapter #5
FIGURE 5-1 Types of joints. © Cengage Learning 2012
Welding Joint Design & Welding Symbols – Chapter #5
FIGURE 5-2 Two ways of fitting up an outside corner joint. © Cengage Learning 2012
FIGURE 5-3 Edge joints. © Cengage Learning 2012
Open Corner Closed Corner
Welding Joint Design & Welding Symbols – Chapter #5
NOTE: "fillet weld" = a triangular shaped weld in a corner
Name three types of joints that use fillet welds?
Welding Joint Design & Welding Symbols – Chapter #5
Accessibility for welding Strength requirements Cyclic or static loading Material thickness Welding process to be used Material type Code Requirements Cost
Side Note: some considerations in selecting a type of joint to use on a fabrication.
Welding Joint Design & Welding Symbols – Chapter #5
Bevel Groove Vee Groove
J Groove
U GrooveSquare Groove
Name two edge preparations used with butt joints.
Welding Joint Design & Welding Symbols – Chapter #5
Edge preparations used with butt joints.
Welding Joint Design & Welding Symbols – Chapter #5
More Important Groove Preparations:
Bevel Groove – single and double
Vee Groove – single and double
3D Welded Joints.pdf
Welding Joint Design & Welding Symbols – Chapter #5
1
21 2 3
4
Single V Groove
Double V Groove
Welding Joint Design & Welding Symbols – Chapter #5
Cost◦A number of items affect weld cost
FIGURE 5-14 Even a slight change in groove angle can save time and money. © Cengage Learning 2012
Welding Joint Design & Welding Symbols – Chapter #5
Weld Size Weld Faults
Welding Joint Design & Welding Symbols – Chapter #5
NOTE: While Leg Size is the usual method to specify and measure weld size, the Effective Throat is a more accurate measure of fillet weld strength!
EffectiveThroat
Actual ThroatLeg Size2
Leg Size1
TheoreticalThroat
Convexity
¼
How is the size of a fillet determined and what is used to measure it?
Welding Joint Design & Welding Symbols – Chapter #5
1. After selecting specified size gauge from set, measure Leg1
2. Measure Leg2
3. Verify throat with other side of gauge (face of gauge should touch weld)
L1
L2
3/8
How To Use A Fillet Gauge
Welding Joint Design & Welding Symbols – Chapter #5
Undercut – most predominant weld fault
◦Fix: Short arc length, proper amperage and speed
Welding Joint Design & Welding Symbols – Chapter #5
Describe four typical faults in single-pass horizontal fillet welds.
Welding Joint Design & Welding Symbols – Chapter #5
Other typical faults in single-pass horizontal fillet welds:
Porosity:
Lack of shielding gasWet electrodeGreasy material
Welding Joint Design & Welding Symbols – Chapter #5
Other typical faults in single-pass horizontal fillet welds:
Slag Inclusion: Improper cleaning / removal of slag
Welding Joint Design & Welding Symbols – Chapter #5
Porosity
Undercut
Poor Fitup
Lack of Penetration
Welding Joint Design & Welding Symbols – Chapter #5
Welding Joint Design & Welding Symbols – Chapter #5
F = FilletG = Groove1 = Flat2 = Horizontal3 = Vertical4 = Overhead
Welding Joint Design & Welding Symbols – Chapter #5
G = Groove1 = Horizontal Rolled2 = Vertical5 = Horizontal Fixed6 = 45 Incline
Welding Symbols
Welding Joint Design & Welding Symbols – Chapter #5
Welding Joint Design & Welding Symbols – Chapter #5
Welding Symbols (cont’d.)
3 parts of the welding symbol body:
Arrow
Reference Line
Tail
Welding Joint Design & Welding Symbols – Chapter #5
Welding symbols ◦Applied to reference
line at the base Reference lines have
an arrow side (near side) and other side (far side)
FIGURE 5-17 Designating weld location.American Welding Society
No size specified
What if the symbol were on this side?
Sketch the weld required by this symbol.
Welding Joint Design & Welding Symbols – Chapter #5
As you see in this example, the weld symbol usually looks like the weld cross
section shape!
Symbol must be above the reference line
indicating make weld on "Other Side" of joint from where arrow is pointing.
Complete the welding symbol that specifies the weld shown.
Welding Joint Design & Welding Symbols – Chapter #5
1/4
1/4 3/8
1/4
(1/4 x 3/8)
Nothing in the symbol specifies unequal leg size location.
If there are not obvious reasons to put larger leg on one side of joint (e.g. thicker metal), then it must be specified on drawing.
Complete the welding symbol that specifies the weld shown including dimension specifications.
Welding Joint Design & Welding Symbols – Chapter #5
1/4
1/4
3/8
3 /8
1/4
3/8
Complete the welding symbol that specifies the weld shown including dimension specifications.
Welding Joint Design & Welding Symbols – Chapter #5
3/16
3/16
3/16 3 - 9
3/16
3 9
3/16
Sketch the weld required by this symbol including dimensions.
Welding Joint Design & Welding Symbols – Chapter #5
1/2
1/2 2 - 8
2 - 8
1/2
1/2
1/2
2 8
Sketch the weld required by this symbol including dimensions.
Welding Joint Design & Welding Symbols – Chapter #5
1/4
3/8
1 3
1 3
1/4 1 - 3
3/8 1 - 3
Complete the welding symbol that specifies the weld shown including dimension specifications.
Welding Joint Design & Welding Symbols – Chapter #5
1/4
1/2
1/2
2 3 1/2
1/2 x 1/4 2 – 3 ½
1/2 x 1/4 2 – 3 ½
Complete the welding symbol that specifies the weld shown including dimension specifications.
Welding Joint Design & Welding Symbols – Chapter #5
GTAW1/8
Process:
Contour:
Finish ing Method:
1/8
"TIG"FlatWelding
NOTE: The “Weld All Around” symbol is not required for pipe weld connections but may be included for clarity
In other cases, it is needed to specify that requirement
Sketch the weld required by this symbol including dimensions and notes.
Welding Joint Design & Welding Symbols – Chapter #5
GTAW1/8
Process:
Contour:
Finish ing Method:
1/8
"TIG"FlatWelding
NOTE: The “Flag” symbol.
Indicates field weld or on-site welding
Sketch the weld required by this symbol including dimensions and notes.
Welding Joint Design & Welding Symbols – Chapter #5
NOTE: The broken arrow line should be used to point at the side to be prepared.
NOTE: The vertical line must always be on the left side.
Complete the welding symbol that specifies the weld shown.
Welding Joint Design & Welding Symbols – Chapter #5
40
3/8
3/840°
Complete the welding symbol that specifies the weld shown including dimension specifications.
Welding Joint Design & Welding Symbols – Chapter #5
Process:
Contour:
Finishing Method:
1/4FCAW
1/4 G
Flux CoredArc Welding
Convex
Grinding
Sketch the weld required by this symbol including dimensions and notes.
Welding Joint Design & Welding Symbols – Chapter #5
3/16
3/16
NOTE: Efforts should be made to avoid Hi/Lows for a smooth surface
SURFACING FUNCTIONS: Buildup Stainless Overlay Abrasion Resistant Overlay
Sketch the weld required by this symbol including dimensions.
Welding Joint Design & Welding Symbols – Chapter #5
2
1/8
1/8 2
Complete the welding symbol that specifies the weld shown including dimension specifications.
Welding Joint Design & Welding Symbols – Chapter #5
1 1/41/8
45 3/8 (1/2)
3/8
1/2SMAW
FCAW
SMAW
3/8
1/8
45°
13/8
1/2
2 3
Sketch the weld required by this symbol including dimensions.
Welding Joint Design & Welding Symbols – Chapter #5