AWS Welding Processes & Equipment Flashcards

What does 'duty cycle' mean for a welding power source?

Answer: The percentage of a 10-minute period that the machine can operate at a rated amperage without overheating

Duty cycle is the percentage of a 10-minute period (or sometimes 100 seconds in some standards) a machine can weld at its rated output without exceeding temperature limits.

In GMAW, 'short-circuit transfer' (short-arc) metal transfer is best suited for:

Answer: Thin gauge material and out-of-position welding at low heat input

Short-circuit transfer uses low voltage and amperage, producing a small, fast-freezing weld pool ideal for thin material and out-of-position welding.

Which polarity is used with an E6010 SMAW electrode for maximum penetration?

Answer: DCEP (direct current electrode positive)

E6010 uses DCEP (reverse polarity), which concentrates 2/3 of the heat at the electrode and provides deep penetration.

What is the purpose of 'wire feed speed (WFS)' in GMAW?

Answer: It controls the rate at which electrode wire is fed to the arc, which determines amperage

Wire feed speed determines how fast the consumable wire is fed into the arc, which in turn controls the welding current (amperage).

A 'constant voltage (CV)' power source is primarily used with which welding process?

Answer: GMAW and FCAW

Constant voltage (CV) power sources are designed for continuous wire feed processes like GMAW and FCAW, providing self-regulation of arc length.

In GTAW, what is the purpose of 'back-purging' when welding stainless steel or titanium pipe?

Answer: To flood the inside of the pipe with inert gas, preventing oxidation of the root weld

Back-purging fills the pipe interior with argon or nitrogen to protect the weld root from atmospheric oxidation during GTAW.