Welding Techniques & Process Control Flashcards
7 cards from real SAW 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 & Process Control flashcards as text
What happens to weld bead convexity when arc voltage is set too low in SAW?
Answer: The bead becomes high and narrow (ropy)
Low arc voltage produces a short, constricted arc that deposits metal in a high, narrow, ropy bead shape.
In SAW, what is 'electrode extension' (also called stick-out) and how does increasing it affect the process?
Answer: Distance from contact tip to work; increasing it raises deposition rate via resistive heating
Electrode extension is the wire length from contact tip to arc; longer stick-out increases resistive preheating, boosting deposition rate while reducing penetration.
Which condition causes 'cold lapping' (lack of fusion at the toes) in SAW?
Answer: Insufficient current for the joint thickness
Insufficient welding current delivers too little heat to fuse the base metal at the weld toes, causing lack-of-fusion defects.
What is the recommended action if porosity is found in an SAW weld and the flux was stored in a humid environment?
Answer: Re-dry the flux at the manufacturer's recommended temperature and time
Absorbed moisture in flux releases hydrogen and steam during welding, causing porosity; re-drying at the correct temperature removes it.
In SAW process control, what does a 'constant voltage' (CV) power source primarily regulate?
Answer: Arc voltage, allowing current to vary with arc length changes
A CV power source maintains a preset voltage, and the arc self-regulates by drawing more or less current as arc length fluctuates.
When making a circumferential weld on a pipe using SAW in the flat position, what technique prevents the molten pool from running ahead of the arc?
Answer: Positioning the electrode slightly behind the pipe's top-center point
Offsetting the electrode slightly back from the 12-o'clock position lets gravity keep the pool from flowing ahead and undermining the arc.
What effect does using a finer-mesh flux granulation have on the SAW arc?
Answer: Smoother arc with finer bead finish but reduced flux permeability
Fine-mesh flux creates a denser, less permeable blanket that smooths the arc and bead surface but can trap gases if too tightly packed.