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52 Cards in this Set
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- Back
- 3rd side (hint)
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.... ..... Is an arc welding process in which metals are joined using an electric arc established between a continuously fed bare metal consumable electrode or electrodes and the work |
Submerged arc welding |
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Which positions can submerged arc welding be conducted in? |
Flat and horizontal |
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Which power sources does SAW use? AC or DC? Constant current or constant voltage? |
All of the above |
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Which polarity is generally used for submerged arc welding? |
DC reverse polarity (electrode positive) is generally used for maximum penetration DC straight polarity is used for maximum deposit rates and AC is used to control arc blow. |
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What apparatus are used for submerged arc welding due to the restriction of positions it can weld at |
Positioners and fixtures Varrying speed trunion type roles Tilting/ rotating positioners Side beam carriage unit |
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What is the primary purpose of the mineral flux ingredient for submerged arc welding? |
To shield the metal from atmospheric contamination |
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A screw type work lead connection is recommended for submerged arc welding due to its... |
Higher currents that are used |
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What is the range of output currents for submerged arc welding? |
400 ampers to more than 1000 ampers |
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For which situations is a constant voltage machine suitable for submerged arc welding? |
Small electrode diameters ranging from 5/ 64 to 1/ 8 because a fast response time is required for a stable arc |
Think electrode size |
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For which scenarios is a constant current machine used for submerged arc welding? |
When using larger diameter electrodes (5/ 32 or greater) the wire feeder has a very stable arc. Larger diameter electrodes are generally fed at a slower rate |
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When multiple wires are fed to the weld zone, what can become a problem using DC current? |
ARC blow |
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Why does a square sign wave provide a more stable arc? |
Because polarity reversals are instantaneous |
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The control unit for submerged arc welding coordinates which variables? |
Arc voltage STOP/START Amperage Arc voltage Travel speed Wire feed FLUX DELIVERY |
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Which type of rollers do submerged arc welding machines use? |
Knurled or v-groove |
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What is the most influential variable in submerged arc welding? |
Amperage |
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...... Is the force that's overcomes resistance to allow amperage flow? |
Voltage |
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How does voltage affect the finished weld Bead? |
It creates a wider flatter bead |
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Electrode ..... Has a direct effect on the weld bead shape and depth of penetration |
Electrode diameter |
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What is the recommended stick out for submerged arc welding? |
Eight times the diameter of the electrode |
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What happens if the flux layer is too deep? |
The arc is restricted which results in a rough looking and ropy bead |
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What happens if the flux layer is too shallow? |
The arc will only be partially submerged which results in flashing and sputtering and may lead to porosity |
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The general rule of thumb, What is the appropriate depth of flux? |
When it is fully submerged with no flashing |
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What is the primary and secondary purpose of copper coating on electrodes? |
Improve the electrical conductivity Which extends the life of the contact tube
Providing a degree of corrosion and oxidation resistance to the wire
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What is the main difference between the classification systems for GMAW FCAW MCAW and SAW |
SAW flux and electrode are identified together |
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____ fluxes are manufactured by the mixture of ____ ___, ___ ____ and ___ ___. |
Fused Silica sand Metal oxides Halide salt |
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_____ fluxes are a mixtures of finely divided oxides of two or more metals such as |
Bonded
Alkaline earth Magnesium Aluminum Silicon Titanium Zirconium |
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_____ fluxes do not significantly change weld metal chemical analysis. |
Neutral |
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____ fluxes are generally used to add alloying elements into the weld. They contain deoxidizes to improve resistance to porosity and weld cracking Used to make single pass welds |
Active |
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___ fulxes generally contain enough alloy metal in their composition to produce an alloy weld using carbon steel electrode. Can also be used for stainless steel and hard facing applications. |
Alloy |
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What are the three possible reasons, related to the electrode, for porosity when using sub arc welding? |
Dump or dirty wire Wet flux Contaminated flux |
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What are the two reasons, related to the pock marks appear on the surface when sub arc welding? |
Dirty wire Insufficient deoxidizers in the wire or flux |
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What is the minimum thickness that sub arc welding is suited for? |
3/16 in thick |
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What type of output slope does saw power sources use? |
Constant current and constant voltage |
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What duty cycle rating is recommended for most SAW power sources? |
100% |
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Saw maybe used in semi-automatic or automatic operation modes. True or false? |
True |
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What is the advantage of using an AC power source for SAW? |
It minimizes arc blow with multiple wire setups |
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What will usually result if the drive roll pressure is set too low? |
The wire electrode will slip and feed erratically |
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How will the arc react if the flux layer is too shallow? |
The weld will be flashing and will likely result in porosity |
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Which is helix? |
The space between two unstrained loops of wire |
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What type of drive rolls are normally used with SAW? |
Knurled or v groove |
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What type of wire feed setup is used with CV, power sources? |
Constant speed |
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To increase arc length when you are welding with SAW, What would you do? |
Increase arc voltage |
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When using SAW, an increase in the arc voltage produces a |
Wider arc stream and shallower penetration |
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When is DCEN used with saw? |
When shallower penetration is required |
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What diameters are saw electrodes available in? |
1.6 mm to 6.4 mm 1/ 16 to 1/ 4 in |
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What is the main difference between the CSA and AWS classification systems for SAW electrode wires? |
CSA uses the metric system to measure tensile strength values |
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Which type of flux can be reused? |
Fused |
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Which type of SAW flux is generally used for the addition of alloying elements. These fluxes contain the deoxidizers to improve resistance to porosity and weld cracking. |
Active flux |
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What should be done with saw fluxes after they have become exposed to moisture? |
They should be dried or rebaked according to manufacturer specifications |
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Are high deposition rates obtainable with saw process? |
Yes |
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How can arc blow be resolved in SAW? |
AC power sources with either constant current or constant voltage output slope can be used |
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Which flux contains no deoxidizes.Can be used for multi-pass applications |
Neutral |
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