Welding Chapter 11 and 12 Test Already Passed

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Welding Chapter 11 and 12 Test Already Passed ___ rapidly expand and push the surrounding air away from the molten weld pool. ✔✔Gas formers _____ all help remove oxides, and/or nitrides in the ... weld. ✔✔Aluminum, silicon, and titanium _____ are added to the flux and form a slag. ✔✔Potassium, sodium, and zirconium _____ can be added to improve hardness, strength, creep resistance, and corrosion resistance. ✔✔Carbon, chromium, and vanadium _____ helps the weld by protecting the hot metal from the effects of the atmosphere. ✔✔Slag ______ is increased and ____ is decreased as the electrode extension is shortened. ✔✔Penetration, buildup ______ provide the necessary shielding because they do not form compounds with any other substance. ✔✔Inert gas A ____ gap may require_____. ✔✔narrow, more penetration A _____ must be chained securely in place before the valve protection cap is removed. ✔✔shielding gas cylinder A weld that is high and has little or no fusion is too "cold." To correct this, ______. ✔✔stop welding and make the needed adjustments Adding oxygen or carbon dioxide to an inert gas causes the shielding gas to become ____, which may cause ____ in some ferrous materials. ✔✔oxidizing, porosity An electrode specifically designed for use with 100% CO2 will have higher levels of ___ to compensate for the losses to oxidation. ✔✔silicon and manganese As the electrode extension as shortened, the welding current _____. ✔✔decreases At any one voltage setting, ____ amperage is required to melt the wire the ___ it is fed. ✔✔more, faster Atmospheric contamination of molten weld occurs ____. ✔✔as it travels across the arc gap and within the pool before it solidifies Electrode wire has a natural curve that is known as its _____. ✔✔cast FCA welding deposition rates of more than ____ lbs/hr. of weld metal are positive. ✔✔25 From 75% to 95% of the weight of ____ electrodes is metal, whereas ____ have a maximum of 75% filler metal. ✔✔FCAW, SMAW High gas flow rates _____. ✔✔waste shielding gases How is the amperage adjusted on a FCA welding machine? ✔✔Changes in the wire feed speed automatically change the amperage If the voltage and wire feed speed are not changed but a larger wire size is used, the _____. ✔✔amperage would automatically go up In FCAW ____ % of the electrode is used. ✔✔nearly 100 In FCAW, atmospheric shielding is _____. ✔✔provided by flux sealed within the tubular electrode, but extra shielding may be supplied through a nozzle In GMA welding, the voltage is set ____ and the amperage is set ____. ✔✔on the welder, by changing the wire-feed speed In the flux classification system, the letter "G" is used to indicate _____. ✔✔an unspecified classification Mixtures of argon with less than ____ percent carbon dioxide may not have enough arc voltage to give desired results. ✔✔ten Slight changes in ___ can be used to control the weld as the groove spacing changes. ✔✔welding gun angle The _____ density of a gas, the ____ will be the flow rate required for equal arc protection. ✔✔lower, higher The addition of ____ gives FCAW the high level of reliability needed for welding on boilers, pressure vessels, and structural steel. ✔✔flux The American Welding Society defines ____ as the linear rate at which the arc is moved along the weld joint. ✔✔travel speed The correct flow rate of shielding gas can be set by _____. ✔✔check welding guides The longer the ____, the greater the _____ to the welding current. ✔✔electrode extension, resistance The main limitation of flux cored arc welding is that _____. ✔✔it is confined to ferrous metals and nickel-bases alloys The major advantages of the vertical down position technique are _____. ✔✔Speed, shallow penetration, and good bead appearance The major atmospheric contaminations come from _____. ✔✔oxygen and nitrogen The most popular electrode diameters range from ____ to ____. ✔✔.035 inch, 3/32 inch The only difference between all GMA welding machines and some FCA welding machines is that all GMA welding machines must have a _______. ✔✔shielding gas solenoid The wire feed speed on charts are generally given in ______. ✔✔inches per minute To make threading electrode wire easier, _____. ✔✔straighten about 12 in. (305 mm) of the end of the wire and cut off any kinks Too light of a feed roller pressure can _______. ✔✔cause erratic wire feeding What can be done to counteract the loss of certain alloying elements such as chromium, vanadium, aluminum, titanium, manganese or silicon? ✔✔Add a deoxidizer to the filler wire When the electrode provides all of the the shielding, it is called ______. ✔✔self shielding When used as pure gases for welding ferrous metals, ______ may produce an erratic arc action, promote undercutting, and result in other flaws. ✔✔argon and helium Which of the following is a similarity between FCAW and GMAW? ✔✔Both use CP welding power supplies Which of the following is true of FCAW? ✔✔The addition of deoxidizers eliminates most of the pre cleaning required Which of the following is true of lime-based flux? ✔✔It is generally unsuitable out of position Which of the following is true of making high- quality welds? ✔✔It is affected by the weather Which of the following is true of mill scale? ✔✔The porosity it causes is most often confined to the interior of the weld Which of the following is true of short-circuiting arc metal transfer in the overhead position? ✔✔It has less molten weld pool sag Which of the following is true of wire electrodes? ✔✔storage in an electric rod [Show More]

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