Welding and Cutting Processes 1 Flashcards
6 cards from real Millwright Certification practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Welding and Cutting Processes 1 flashcards as text
Which welding process uses a non-consumable tungsten electrode and a separate filler rod?
Answer: GTAW (TIG welding)
GTAW (TIG) uses a non-consumable tungsten electrode to create the arc while filler metal is added manually with a separate rod, making it ideal for precise, high-quality welds on thin or critical materials.
What is the correct sequence for shutting down an oxy-acetylene torch at the end of a job?
Answer: Close the acetylene valve first, then the oxygen valve, then bleed the lines
Closing acetylene first extinguishes the flame safely and prevents a backfire or soot deposit in the tip. Oxygen is then closed, and lines are bled to relieve pressure and prevent hose deterioration.
In SMAW (stick) welding, what is the purpose of the flux coating on the electrode?
Answer: To shield the weld pool from atmospheric contamination and form slag
The flux coating burns and vaporizes to produce a shielding gas cloud around the arc and molten pool, keeping out oxygen and nitrogen. It also forms a slag layer over the bead that protects the weld as it cools.
A millwright notices porosity in a completed weld bead. What is the most likely cause?
Answer: Contamination or moisture in the weld zone
Porosity (gas pockets trapped in the solidified weld) is almost always caused by contaminants such as oil, moisture, rust, or paint releasing gases into the molten pool faster than they can escape before solidification.
When cutting with a plasma arc system, what material conducts the return current path back to the power supply?
Answer: The work clamp (ground) attached to the workpiece
The work clamp completes the electrical circuit. Current flows from the power supply through the torch electrode, through the plasma arc into the workpiece, and returns via the work clamp cable. Without a solid work connection the arc will not transfer.
What type of flame is used when oxy-acetylene welding most steel and iron?
Answer: Neutral flame (balanced oxygen and acetylene)
A neutral flame has equal volumes of oxygen and acetylene, producing a clean, balanced combustion that neither adds carbon to nor removes carbon from the base metal. It is the standard flame for welding most ferrous metals.