CWI Welding Process Fundamentals 2

Question 1

In GMAW, what is the primary function of the shielding gas?

Accepted Answer

To protect the weld pool from atmospheric contamination

Answer

Shielding gas in GMAW surrounds the arc and weld pool to prevent oxidation and contamination from oxygen, nitrogen, and hydrogen in the atmosphere.

Question 2

Which GMAW transfer mode is best suited for welding thin sheet metal in all positions?

Accepted Answer

Short-circuit transfer

Answer

Short-circuit transfer uses low heat input and a small, fast-freezing weld pool, making it ideal for thin materials and out-of-position welding.

Question 3

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

Accepted Answer

The percentage of a 10-minute period the machine can weld at a rated current

Answer

Duty cycle is the percentage of a 10-minute interval during which a welding machine can operate at its rated output without overheating.

Question 4

In SAW (Submerged Arc Welding), what is the role of the flux?

Accepted Answer

It shields the arc, refines the weld metal, and can add alloying elements

Answer

SAW flux covers the arc to prevent atmospheric contamination, stabilizes the arc, and can contribute alloying elements and remove impurities from the weld pool.

Question 5

What is the primary advantage of using a constant voltage (CV) power source for GMAW?

Accepted Answer

It self-corrects arc length by automatically adjusting current as wire feed rate varies

Answer

A CV power source maintains relatively constant voltage; when arc length changes, the machine adjusts amperage to restore the set voltage, providing self-regulation.

CWI Practice Test

CWI Practice Test

CWI Welding Process Fundamentals 2