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37 Cards in this Set
- Front
- Back
Uses any type of extinguisher. Wood, paper, rubber fires |
Class A |
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CO2 or dry chemical extinguisher. Oil and gas fires. |
Class B |
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Dry chemical extinguisher. Electrical fires. |
Class C |
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A gas shielded arc welding process, uses consumable electrode wire that is continuously fed in the arc. |
GMAW gas metal arc welding |
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Heat input per linear foot compared to SMAW is.... |
Less |
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Good ventilation is needed for GMAW as shielding gases can displace.... |
Oxygen |
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GMAW power source is.... |
CV or CP |
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GMAW CV or CP current is usually... |
DCEP, DCRP, DC+ |
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Protects the molten puddle from atmospheric contamination ( oxygen, nitrogen, hydrogen) |
Shielding gases |
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Shielding Gas.. >heavier than air >good on alumin., copper, nickel, and titanium. >lower heat and narrower penetration >inert gas |
Argon |
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Shielding Gas... >lighter than air >used on non-ferrous metals (alumn., copper, magnesium) >inert gas >high heat in arc |
Helium |
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Shielding Gas.. >man-made gas, cheap to use >mainly used on mild steel, must be moisture free! >added to mixed gases to reduce undercutting >greatest cooling effect ongun |
CO2 |
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Shielding gas mixtures, _______ is limited to 5% because additional ________ will cause porosity. |
Oxygen |
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Shielding gases are regulated by these. Measured in CFH (cubic ft per hour) inlet pressure should be 50PSI |
Flow Meter |
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Solid or cored, base metal composition (mild steels, stainless, alumin., ect. ) Provides quality an strengths, shielding gas and current used. |
Filler Wire |
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O2 and CO2 are ______ gases. |
reactive gases |
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Helium and Argon are ________ gases. |
Inert gases |
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Type of metal transfer most frequently used, in all positions. Less than 23 volts and 200 amps. Inductance improves penetration an bead profile |
Short-circuit Transfer (Dip Transfer) |
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Type of metal transfer not used often due to poor arc stability, poor penetration and excessive spatter. |
Globular Transfer |
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Type of metal transfer best on thicker material and non-ferrous metals. Over 24Volts used. Must have mix gas of min. 80% Argon. Highest deposition rate. |
Spray Transfer |
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Squeezing force on an electrode.. |
Inductance. |
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Transfer may cause fusion problems on thicker material... |
Short-circuit Transfer |
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Pieces of wire from sticking to the weld puddle when trigger is released. |
Whiskers. =^.^= |
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Prevents wire from sticking to the weld puddle when trigger is released. |
Burnback |
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When _________ is increased too much stubbing occurs. |
Wire feed speed ( WFS ) |
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Small pinholes in the weld (contamination from atmosphere cause by): excessive gas flow, too little gas flow, dirty ol nozzle, excessive wind or draft. |
Porosity |
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Removal of gun before letting crater solidify |
Crater Cracks |
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Weld doesn't fuse to parent metal |
Lack of Fusion (Cold Lap) |
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Standard sizes of GMAW wire? |
.023", .030", .035", .045" |
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Drive rolls best for GMAW hard wire |
V-Grooved |
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Drive rolls best for GMAW aluminum |
U-Groove |
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Full GMAW gas cylinder pressure |
2200 PSI |
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To prevent dry ice from forming within the flow controls. |
Line Heater |
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Electrode extension for Spray Transfer |
1/2" - 1" |
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A slope of 3-4V per 100 amps is recommended for __________ Transfer. |
Short-circuit |
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90% Helium, 7.5% Argon, 2.5% Oxygen Best shielding gas for welding .... |
Stainless Steel GMAW |
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GMAW wire may need assistance on current in contact tube; prevent corrosion of wire when stored. What coating is applied? |
Copper Coating |