Welding Flashcards
How do you adjust the flame
With just the acetylene burning you adjust the oxygen until a well defined white cone appears with a second bluish cone. At this point you have a betray flame
What is the volume ratio of oxygen to acetylene on a neutral flame
1 to 1
What kind of metals are welded with the neutral flame
Mild steel Stainless Cast iron Copper Aluminum
What is a carbonizing flame
The welding flame has a white inner cone with a white feathered cone enveloped with a blue feather
The metal will boil which allows it to absorb carbon. When cold it becomes brittle and subject to cracking
What is an oxidizing flame
Has a pointed inner cone with a small and narrow outer envelope
Slightly more than 1 volume of oxygen to 1 volume of acetylene
What metals are welded withe oxidizing flame
Zinc
Copper
Manganese steel
Cast iron
What is a flame backfire
This is a loud pop when the flame goes out
What causes backfires on torches
- Operating torch at lower pressures
- Touching tip against the work.
- Overheating the tip
- Obstruction of the top
What does E-6010 stand for
E- electric welding
60- tensile strength
1- welding position
0- special characteristics
What is tensile strength
The resistance of a material to break under tension
Express in psi ( pounds per square inch
What are the different position numbers
1- any position
2- horizontal or flat
3- flat only
What are the special characteristic numbers 0-4
0-cellulose sodium, dcr 1- cellulose potassium, Ac or DCR 2- Titania sodium, Ac or dcs 3-Titania potassium, Ac, DCS or DCR 4- Titania iron powder, all three
What are the special characteristic numbers 5- 8
- Low hydrogen sodium, DCR
- Low hydrogen potassium, AC or DCR
7- iron powder iron oxide, all three
8- iron powder low hydrogen , Ac or DCR
What is polarity
Indicates the direction of current flow
What is DC straight (DCS) polarity
The stinger is connected to the negative and ground to the positive
What is DC reversed (DCR) polarity
Stinger connected to the positive and work connected to the negative
Why choose straight or reversed polarity
Straight gives you more heat when required to melt metal
Reverse gives weld greater holding power by less heat
What are the essentials for arc welding
- Correct electrode
- Correct Arc length
- Correct current
- Correct travel speed
- Correct electrode angle
What are the 4 rules for General welding in the safety appendix
- Wear appropriate gloves
2 appropriate shaded lens for goggles and welding helmets
3 no cutting or welding in areas with combustibles unless precautions have been taken - No cutting or welding on piping or empty or sealed containers unless vented and purged
What are the 8 practices for General welding in the safety appendix
- No low cut shoes with unprotected tops
- No oily or greasy clothing , wear fire retardant clothing
- Shields or barriers for observers
- No cutting or welding directly on concrete
- Don’t leave hot metal unattended unless properly marked
- Adequate ventilation or respirator
- Take precautions for hot falling metal when elevated work
8 no butane lighters
Arc rules from safety appendix
- Welding machine frame grounded
Arc welding practices
- Check cables, holders, grounds, machine ect… For serviceability
Gas welding rules from appendix (3 rules)
- Don’t alter or repair cylinder valves, don’t use a regulator for one type of gas and use on another.
- No oil or grease on or near oxygen
- Never use leaky hoses or couplings
Gas weld practices
7
- Follow all precautions for gas cylinders for storage and handling
- Use only an approved lighter to light a torch
- Always close cylinder valve and release pressure after use
- Never keep a connected torch in a toolbox even if the pressure is released
- Check hoses, fittings, couplings valves, ect for serviceability
- Keep cylinders vertical and secured from falling
- Never place acetylene cylinder horizontally
