Welding Techniques Flashcards
7 cards from real AWS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Welding Techniques flashcards as text
What is 'burn-through' in welding, and which condition most commonly causes it?
Answer: A hole melted through the base metal, commonly caused by excessive amperage or slow travel speed
Burn-through occurs when the heat input is too high or travel speed too slow, melting completely through the base metal and creating a hole in the weld.
In plasma arc welding (PAW), what distinguishes it from conventional GTAW?
Answer: PAW constricts the arc through a copper nozzle orifice, producing a higher energy density plasma jet
PAW passes the arc through a constricting copper nozzle, creating a high-velocity plasma column with greater energy density than GTAW, enabling faster travel speeds and deeper penetration.
Which welding process is most suitable for joining dissimilar metals such as copper to steel?
Answer: GTAW with appropriate filler metal selected for the dissimilar combination
GTAW provides the precise heat control and wide filler metal selection needed for dissimilar metal joints, where controlling dilution and selecting compatible filler metals is critical.
What is the effect of increasing wire feed speed (WFS) in GMAW?
Answer: Increases amperage, deposition rate, and heat input
In GMAW, the wire feed speed directly controls amperage; increasing WFS increases the current drawn, the deposition rate, and the overall heat input into the weld.
What is the recommended technique for restarting a weld bead after an interruption to avoid a visible restart defect?
Answer: Start the arc 1 inch ahead of the crater and weld back into it before continuing forward
Starting slightly ahead of the crater and welding back into it ensures the crater is fully remelted and fused, eliminating cold-lap and lack-of-fusion defects at the restart.
What is the primary reason for using a backing gas (purge gas) on the back side of a stainless steel root pass?
Answer: To prevent oxidation (sugaring) of the root bead and maintain corrosion resistance
Stainless steel oxidizes severely on the back side during root pass welding; argon or nitrogen purge gas displaces oxygen and prevents 'sugaring,' which destroys the chromium oxide passive layer.
Which AWS classification system is used to designate a submerged arc welding (SAW) electrode-flux combination?
Answer: A combined electrode-flux classification (e.g., F7A2-EM12K) indicating flux, strength, and electrode
AWS classifies SAW consumables as a combined electrode-flux designation (e.g., F7A2-EM12K), where the flux and electrode together determine the deposited weld metal properties.