Gas Tungsten Arc Welding (GTAW) WELD 250 Practice Test

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• In GTAW of carbon steel, which filler metal is most commonly used and why?
• Which statement about the effect of a steeper torch angle is true?
• DCEP concentrates heat on the plate and the electrode in which proportions?
• What are the main differences between AC and DC operation in GTAW, and which materials typically require AC?
• Which statement best describes shielding gas purity in GTAW?
• What practice helps minimize porosity related to shielding gas flow during GTAW?
• The term 'TIG' stands for?
• Why should you avoid cross-contamination with carbon steel during cleaning aluminum surfaces before TIG welding?
• The rounded end on a pure tungsten electrode can be prepared by
• What is post-weld heat treatment (PWHT) and when might it be required in TIG welded joints?
• When a tungsten contaminates the molten weld pool, what should be cleaned before resuming?
• Phosgene is formed when ultraviolet radiation decomposes chlorinated hydrocarbon.
• Elements are added to tungsten electrodes to
• Which tungsten electrode is well suited for welding steel and nickel alloys but not aluminum or magnesium?
• What is a reliable way to verify arc stability during GTAW if you cannot measure arc length precisely?
• ____ is denser than air, so it effectively shields welds in deep grooves in the flat position.
• Which bead approach is best for filling wider areas and capping passes on thicker joints?
• In GTAW, how is the bead decreased?
• What does the ER prefix in ER480S-2 indicate?
• ____ is relatively easy to ionize and thus is suitable for alternating-current applications and easier starts
• ____ has the poorest heat resistance and electron emission characteristic of all the tungsten electrodes.
• Which is a common cause of crater cracking in GTAW?
• Which method helps prevent misalignment in TIG weld joints?
• What can cause porosity (tiny bubbles) to form on some welds on mild steel?
• Which statement describes the distribution of arc heat in DCEP?
• What is the purpose of a gas lens in a GTAW torch, and how does it affect shielding gas usage?
• High-frequency starts in TIG welding help avoid which issues?
• Which of the following is an advantage of pulsed GTAW?
• After a GTAW butt weld, what should be verified at the toe to ensure weld quality?
• Which of the following is a true statement about shielding gas in GTAW?
• What is interpass temperature and why is it important in TIG welding stainless steel?
• Which statement best describes DCEN in GTAW?
• DCEN concentrates about ____ of its welding heat on the work, and about ____ on the tungsten.
• Before the joint is assembled, to remove any sources of contamination, clean a ____ inch wide or wider band, both inside and outside of the pipe.
• Which tungsten electrode type has the poorest heat resistance and electron emission characteristics?
• Which gas is described as relatively easy to ionize and suitable for AC starts?
• Which polarity reduces tungsten erosion in GTAW?
• Bead contour is enhanced by surface tension in GTAW for which metal?
• Why are deoxidized filler rods used for welding mild steel?
• Which statement about shielding gas in GTAW is accurate?
• Which statement about shielding gas in GTAW is true based on the material?
• What considerations are important when TIG welding stainless steel to minimize carbide precipitation and intergranular corrosion?
• What is porosity in GTAW and what are common causes?
• What is the typical sequence of passes for a GTAW butt weld on steel, from root to cover?
• What width band around the pipe should be cleaned prior to joint assembly?
• In AC GTAW, the majority of welding heat is delivered to which part?
• To purge the air out of a 10-foot section of 6 inch diameter pipe, if the flow rate is 20 cfh, the flow time will be approximately:
• Which term describes electrode negative polarity in GTAW?
• The problems associated with hot shortness in aluminum welding can be averted by
• Why is back purging used for aluminum TIG welds on thick sections and what gas is used?
• What effect does excessive heat input have on a GTAW weld?
• With ____, lack of cleanliness may cause the weld pool to show overheating and poor gas coverage.
• How must tube- and ball-type flowmeters be mounted?
• In GTAW, when travel speed increases, what happens to heat input?
• What is the purpose of visual inspection (VT) in GTAW quality control, and what would constitute a defect?
• What is the most commonly used groove shape for pipe?
• Why is high frequency stabilization used with AC GTAW?
• Using a smaller-diameter tungsten electrode in GTAW tends to produce which effect on weld penetration?
• What is the rule of thumb for estimating GTAW arc lengths?
• For TIG welding aluminum, which shielding gas is typically used?
• Which practice is most effective in preventing oxidation and porosity when the shielding gas is interrupted?
• What is the primary reason for back purge during aluminum TIG welding on thick sections?
• Which tungsten electrode type is versatile for both AC and DC welding, often used when cleanup is a concern and a stable arc is needed?
• Which polarity results in welds with deep penetration and allows use of a smaller tungsten electrode?
• The solar flux used on stainless steel is Type B.
• Why is an inert shielding gas required for GTA welding?
• In AC TIG welding of aluminum, what is the effect of increasing balance toward cleaning action?
• Which component directs purge gas onto the backside of the weld to prevent oxide formation?
• Which statement about the purge cap is true?
• Which shielding gas is most commonly used for GTAW of carbon steel, and what is a typical flow rate range?
• Surface tension helps hold the metal in place, giving excellent bead contour in GTAW for which metal?
• What grinding angle is typically used for a pointed tungsten on DC steel welds?
• The color band of EWTh-1 tungsten is?
• Which practice minimizes erosion of the tungsten electrode in GTAW?
• Which statement about shielding gas in GTAW is true?
• Which shielding gas is typically used for aluminum GTAW?
• If a tungsten electrode is contaminated and the welding pool is molten, which action should be taken before resuming?
• What is the purpose of a gas lens in GTAW?
• For aluminum GTAW of 6061-T6, which filler metal is commonly used and why?
• What are common safety concerns unique to GTAW fume and how can they be mitigated?
• Which of the following is true about the effects of nozzle cleanliness on weld shielding?
• A constant current power supply is needed for?
• Which tungsten electrode type combination is commonly used in GTAW for DC welding and versatile AC/DC welding?
• Pulsed GTAW has which of the following effects?
• High frequency interference of radio signals can be limited by
• Which acronym indicates Alternating Current High Frequency used to start the GTAW arc?
• Flowmeters measure the flow rate of a shielding gas in which units?
• What are typical indicators of shielding gas contamination or improper gas flow during GTAW?
• In GTAW, which method helps reduce repairs when work has to be done in a limited space?
• What component is often used to direct purge gas along the backside during aluminum TIG welding?
• Compare stringer beads and weaving beads in GTAW and indicate typical use cases.
• What is the main purpose of PPE in GTAW, and what are two essential items?
• Which gas is typically used as shielding gas in aluminum GTAW?
• When welding dissimilar metals, what is essential about filler metal?
• In DCEN operation, which of the following is true about arc behavior?
• Why is regular tungsten electrode maintenance essential for GTAW and what signs indicate replacement is needed?
• When would you employ high-frequency TIG welding and what benefit does it provide?
• Which factor is a prime cause of burn-through in GTAW?
• For a DC TIG weld on steel, what electrode shape is typical and why is grinding angle important?
• Flowmeters measure the shielding gas flow rate in CFH or L/min. Which option below reflects this?
• What pre-weld cleaning steps are recommended for carbon steel vs aluminum in GTAW?
• A ____ degree angle or less to the plate surface prevents air from being pulled into the welding zone behind the rod.
• The greater the contamination of a stainless-steel weld, of the bead after the weld?
• ____ is very well suited for making welds on steel, steel alloys (including stainless), nickel alloys, and most other metals other than aluminum or magnesium.
• When setting up to weld on low carbon steel with GTAW, how should the tungsten be prepared and what polarity should the machine be set to?
• Which AWS codes are commonly referenced for TIG welds on steel and aluminum, respectively?
• Carbide precipitation occurs in some stainless steels when they are kept at a temperature between ____ degrees Fahrenheit for a long period of time.
• What is the primary purpose of a foot pedal in TIG welding?
• What is the best description of the role of shielding gas in GTAW?
• The recommended postflow time when welding at 140 amps is approximately
• Why are the ends of tack welds ground to a featheredge?
• What is the rule of thumb for estimating GTAW stickout?
• Which statement best describes the up slope in GTAW controls?
• Two of the most common root defects are ____?
• Which of the following is NOT a typical indicator of shielding gas contamination or improper flow?
• What is a typical interpass temperature limit for TIG welding stainless steel according to common practice?
• What method is recommended to locate a gas leak around the TIG torch?
• What is a lift-arc start in GTAW and how does it differ from a scratch start?
• When performing a root pass and a subsequent fill pass in GTAW, what is the transition point for beginning filler metal?
• Which tungsten preparation would be selected for welding with EWTh-2?
• What is a typical sign of a gas leak around the TIG torch?
• In GTAW, the acronym TIG stands for
• What strategies help minimize distortion during GTAW of a thin-walled component?
• Which statement about shielding gas in GTAW is true?
• EWTh-1 tungsten color band identification.
• If the end of the filler rod is removed from shielding gas protection, ____.
• What type of welding power source is used for GTAW?
• For TIG welding carbon steel, when is preheating recommended and what is the typical preheat range?
• Which statement accurately describes back purging in aluminum TIG welding?
• What is hot shortness?
• Which colors describe the oxide layers on aluminum and iron respectively, as given in the material?
• Which statement accurately describes heat distribution when using DCEN?
• Using a ____ arc current setting with ____ travel speeds is important when welding stainless steel.
• Which tungsten electrode type is most commonly used for DC TIG welding of steel?
• What is the purpose of purge gas in aluminum TIG welding and how is it applied?
• DCEP GTAW is usually limited to which metals?
• What is the purpose of a purge cap in aluminum TIG welding, and when should it be used?
• The phrase 'minimize heat input' is used to control which welding-related phenomenon in stainless steel?
• The V-groove is the most commonly used groove shape for pipe welding. Which choice best reflects this fact?
• In the filler rod designation ER480S-2, the letter S stands for
• Which gas is inert?
• How should filler metal be selected when welding stainless steel to maintain corrosion resistance?
• Which of the following statements best identifies a root defect in GTAW?
• Differentiate between undercut and lack of fusion in a GTAW weld.
• What are critical fit-up considerations for a GTAW root pass on a thick plate?
• What is hydrogen porosity in GTAW of steels and how can it be prevented?
• The post-flow period protects the molten weld pool, the filler rod, and the tungsten electrode as they cool to a temperature at which they will not oxidize rapidly.
• Concavity of the root surface is detected by ____.
• Which welding position typically yields the easiest control for GTAW and why?
• In the designation ER480S-2, what does the S denote?
• AC concentrates about ____ of its welding heat on the work and ____ on the tungsten.
• What is the current used for welding stainless steel with GTAW?
• How does increasing AC frequency affect arc stability and weld pool behavior in aluminum TIG welding?
• Hot shortness is described as which phenomenon?
• Which tungsten electrode type is described as having the poorest heat resistance and electron emission characteristics?
• _________ is formed when ultraviolet radiation decomposes chlorinated hydrocarbon.
• Which practice is essential when using a GTAW power source?
• At approximately 140 amps, what is the recommended postflow time?
• Which combination of arc current and travel speed is recommended for stainless steel welding?
• The arc length rule of 1.5 times the electrode diameter specifically refers to which component's diameter?
• In pipe welding, what is the most commonly used groove shape?
• How can you estimate arc length without specialized tools during GTAW?
• What is the effect of a gas lens on shielding gas flow?
• In AC TIG welding of aluminum, how does increasing the AC frequency generally affect the arc?
• What cleaning practices before GTAW help ensure weld quality?
• Which term describes electrode positive polarity in GTAW?
• In AC GTAW, which area receives the majority of welding heat?
• Which of the following is an inert shielding gas commonly used in GTAW?
• Which polarity is used for welding stainless steel with GTAW?
• Which statement best describes the relationship between shielding gas flow, torch size, and joint size in GTAW?
• What is the typical torch angle to the work for TIG welding to balance bead shape and penetration?
• What is the control used to initiate the current at a lower amperage than the set welding current called?
• An oxide layer on aluminum is ____, while on iron it is ____.
• How does arc length influence penetration, bead shape, and shielding effectiveness in GTAW?
• In AC welding using the GTAW process, part of which half cycle is reduced?
• In GTAW, cleanliness is particularly critical for which material?
• What is recommended before TIG welding aluminum to prevent porosity?
• With which gas, penetration and bead profile are sensitive to arc length, and long arcs for feeding filler wires are more difficult to control?
• How can a welder improve the shielding gas coverage of a weld?
• Using DCEP when welding with GTAW is usually limited to which types of metals?
• Which statement is true about Direct Current Electrode Positive (DCEP) in GTAW?
• What welding technique can be used to reduce fatigue, improve torch control, and make longer high-quality welds?
• What does the 480 refer to in the filler rod designation ER480S-2?
• Which statement correctly describes the heat distribution in AC GTAW?
• Beyond galvanic corrosion and thermal expansion, what other factor is critical when selecting filler metal for dissimilar metal GTAW?
• What is the effect when metal particles stick to the inside of the ceramic nozzle?
• Which property makes Argon especially effective for shielding welds in deep grooves?
• What is the recommended surface-preparation sequence for stainless steel prior to TIG welding?
• When GTAW welding dissimilar metals, which issue is a primary concern?
• In GTAW, the high-frequency may be set so that it behaves differently for DC and AC. Which pairing is correct?
• Carbide precipitation is the combining of ____.
• When the EWZr electrode is not available, which of the following electrodes should you select for welding aluminum?