Mod #4 - SMAW (Stick Welding) - Questions
What are some of the advantages of stick welding? Hint: 4 things
1. Equipment relatively simple and inexpensive 2. Quite portable a. Engine driven units for remote locations b. Solid state units small enough to be carried 3. Electrode technology improved with numerous types available 4. High quality results
What are some of the causes/effects of porosity in SMAW?
1. Moisture in weld region from electrode coating, base metal, or atmosphere 2. Long arcing with low hydrogen electrodes 3. Starting porosity effecting arc stability at start and lack of coating at extreme end of electrode
What are some possible problems with SMAW? Hint: 9 things
1. Porosity 2. Slag inclusions 3. Improper fusion 4. Improper penetration 5. Cracking 6. Undercut 7. Overlap 8. Incorrect weld size 9. Incorrect weld profile
What does your SMAW equipment consist of? Hint: 4 things
1. Power source 2. One electric lead to work 3. One electric lead to electrode holder 4. Electrode in holder
Shielding gas: 1. Where does it come from? 2. What does it do?
1. Released from decomposing flux 2. Assists flux in shielding the molten metal
What are the 5 functions of SMAW electrode coatings? Hint: S, D, A, I, I
1. Shielding 2. Deoxidation 3. Alloying 4. Ionizing 5. Insulating
What are the limitations of stick welding?
1. Slower than some other processes a. Welder must stop to change electrodes b. Must remove slag 2. Low hydrogen electrodes require special storage
What are some effects of Arc Blow? Hint: 4 things (S, U, I, D)
1. Spatter 2. Undercut 3. Improper weld contour 4. Decreased penetration
What are some solutions for Arc Blow? Hint: 10 Things
1. Switch to AC 2. Use short arc 3. Reduce current 4. Angle the electrode opposite the arc blow 5. Use heavy tack welds at the end and along weld length 6. Weld towards heavy tack or completed weld 7. Use backstep technique 8. Move ground connection 9. Wrap part with ground cable 10. Add runoff plate to extend joint
Identify the parts of the SMAW electrode ID system: EXXXX A= First 2 X's B= Third X C= Final X
A. Tensile strength B. Position C. Coating/operating characteristics
What type of electrode is AWS-A5.3
Aluminum and Aluminum Alloys
A decrease in arc voltage results in?
An increase in current (heat)
What type of electrode is AWS-A5.1?
Carbon steel
What type of electrode is AWS-A5.15?
Cast Iron
What type of electrode is AWS-A5.6?
Copper and Copper alloys
What type of electrode is AWS-A5.4?
Corrosion resistant steel
Shielding (in SMAW) comes from?
Decomposition of the electrode flux coating
Arc between electrode and base metal provides?
Heat, or energy, to melt base metal, filler metal, and electrode coating
Why does slag tend to float to the outside?
It solidifies after the molten metal, reducing the likelihood of slag inclusions
What type of electrode is AWS-A5.5
Low Alloy Steel
Electrodes ending in 5, 6, or 8 are designated as?
Low hydrogen types that require special storage conditions (original air tight container or electrically heated oven with vent)
What is arc blow?
Magnetic arc deflection caused by welding near edge of plate or in corners
What type of electrode is AWS-A5.11
Nickel and Nickel alloys
The next to last digit in an electrode ID refers to?
Possible welding positions. 1 = suitable for all positions 2 = flat and horizontal fillet positions only (molten metal too fluid)
What is an electrode made of?
Solid metal core with a granular flux coating
What type of electrode is AWS-A5.13 and A5.21?
Surfacing
The first 2 or 3 digits in an electrode ID refer to what?
The as-deposited minimum tensile strength in thousands of pounds per square inch
Arc length is?
The distance from the electrode end to the workpiece
What feature classifies the different types of electrodes?
The electrode coating
Alloying is provided by?....and why?
The electrode coating because it's more economical
Filler metal is supplied by?
The electrode core wire and covering (iron powder and alloys)
SMAW uses? Hint: describe process
The heat of an electric arc between a covered metal electrode and the work
The last digit on an electrode ID refers to?
The type of coating, which in turn defines electrical characteristics, arc action, penetration ability and presence of iron powder