Chapter 5 Welding Joint Design and Welding Symbols

Chapter 5 Welding Joint Design and Welding Symbols

Objectives 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

Weld Joint Design 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

Name five basic weld joints that may be found in a weldment. Butt Joint Lap Joint Corner Joint Tee Joint Edge Joint Welding Joint Design & Welding Symbols – Chapter #5

FIGURE 5 -1 Types of joints. © Cengage Learning 2012 Welding Joint Design & Welding Symbols – Chapter #5

Open Corner Closed Corner FIGURE 5 -2 Two ways of fitting up an outside corner joint. © Cengage Learning 2012 FIGURE 5 -3 Edge joints. © Cengage Learning 2012 Welding Joint Design & Welding Symbols – Chapter #5

Name three types of joints that use fillet welds? NOTE: "fillet weld" = a triangular shaped weld in a corner Welding Joint Design & Welding Symbols – Chapter #5

Side Note: some considerations in selecting a type of joint to use on a fabrication. Accessibility for welding Strength requirements Cyclic or static loading Material thickness Welding process to be used Material type Code Requirements Cost Welding Joint Design & Welding Symbols – Chapter #5

Name two edge preparations used with butt joints. Bevel Groove Vee Groove J Groove Square Groove U Groove 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 3 D Welded Joints. pdf Welding Joint Design & Welding Symbols – Chapter #5

Name two types of V edge preparations that are recommended for braze welding butt joints. Single V Groove Double V Groove 1 2 3 1 4 2 Welding Joint Design & Welding Symbols – Chapter #5

Weld Joint Design (cont’d. ) 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 Quality Weld Size Weld Faults Welding Joint Design & Welding Symbols – Chapter #5

How is the size of a fillet determined and what is used to measure it? 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! Convexity Leg Size 2 Actual Throat Effective Throat ¼ Leg Size 1 Theoretical Throat Welding Joint Design & Welding Symbols – Chapter #5

How To Use A Fillet Gauge 1. After selecting specified size gauge from set, measure Leg 1 2. Measure Leg 2 3. Verify throat with other side of gauge (face of gauge should touch weld) L 1 3/8 L 2 Welding Joint Design & Welding Symbols – Chapter #5

Weld Quality (cont’d. ) 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 gas Wet electrode Greasy 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

Weld Quality - Review Undercut Porosity Poor Fitup Lack of Penetration Welding Joint Design & Welding Symbols – Chapter #5

Weld Position (Plate) F = Fillet G = Groove 1 = Flat 2 = Horizontal 3 = Vertical 4 = Overhead Welding Joint Design & Welding Symbols – Chapter #5

Weld Position (Pipe) G = Groove 1 = Horizontal Rolled 2 = Vertical 5 = Horizontal Fixed 6 = 45 Incline Welding Joint Design & Welding Symbols – Chapter #5

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: Reference Line Tail Arrow Welding Joint Design & Welding Symbols – Chapter #5

Weld Location 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

Sketch the weld required by this symbol. What if the symbol were on this side? No size specified Welding Joint Design & Welding Symbols – Chapter #5

Complete the welding symbol that specifies the weld shown. Symbol must be above the reference line indicating make weld on "Other Side" of joint from where arrow is pointing. As you see in this example, the weld symbol usually looks like the weld cross section shape! Welding Joint Design & Welding Symbols – Chapter #5

Complete the welding symbol that specifies the weld shown including dimension specifications. 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. Welding Joint Design & Welding Symbols – Chapter #5

Complete the welding symbol that specifies the weld shown including dimension specifications. 1/4 3/8 Welding Joint Design & Welding Symbols – Chapter #5

Sketch the weld required by this symbol including dimensions. 3/16 3 9 Welding Joint Design & Welding Symbols – Chapter #5

Sketch the weld required by this symbol including dimensions. 2 8 1/2 1/2 Welding Joint Design & Welding Symbols – Chapter #5

Complete the welding symbol that specifies the weld shown including dimension specifications. 3/8 1/4 1 -3 Welding Joint Design & Welding Symbols – Chapter #5

Complete the welding symbol that specifies the weld shown including dimension specifications. 1/2 x 1/4 2– 3½ Welding Joint Design & Welding Symbols – Chapter #5

Sketch the weld required by this symbol including dimensions and notes. 1/8 "TIG" Flat Welding 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 Welding Joint Design & Welding Symbols – Chapter #5

Sketch the weld required by this symbol including dimensions and notes. 1/8 "TIG" Flat Welding NOTE: The “Flag” symbol. Indicates field weld or on-site welding Welding Joint Design & Welding Symbols – Chapter #5

Complete the welding symbol that specifies the weld shown. 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. Welding Joint Design & Welding Symbols – Chapter #5

Complete the welding symbol that specifies the weld shown including dimension specifications. 3/8 40° Welding Joint Design & Welding Symbols – Chapter #5

Sketch the weld required by this symbol including dimensions and notes. Flux Cored Arc Welding Convex Grinding Welding Joint Design & Welding Symbols – Chapter #5

Sketch the weld required by this symbol including dimensions. NOTE: Efforts should be made to avoid Hi/Lows for a smooth surface SURFACING FUNCTIONS: § Buildup § Stainless Overlay § Abrasion Resistant Overlay 3/16 Welding Joint Design & Welding Symbols – Chapter #5

Complete the welding symbol that specifies the weld shown including dimension specifications. 1/8 2 Welding Joint Design & Welding Symbols – Chapter #5

Sketch the weld required by this symbol including dimensions. 3/8 45° 3/8 1 2 1/8 3 1/2 Welding Joint Design & Welding Symbols – Chapter #5