AWS AWS Welding Processes & Equipment

Question 1

In GMAW (MIG welding), what is the primary function of the shielding gas?

Accepted Answer

To protect the molten weld pool from atmospheric contamination (oxygen and nitrogen)

Answer

Shielding gas in GMAW protects the weld pool from oxygen and nitrogen in the atmosphere, preventing porosity and oxidation.

Question 2

Which SMAW electrode coating type produces a low-hydrogen deposit and requires storage in a rod oven?

Accepted Answer

E7018 (low-hydrogen iron powder)

Answer

E7018 is a low-hydrogen electrode that must be kept dry (stored in a rod oven at 250–300°F) to prevent moisture pickup and hydrogen-induced cracking.

Question 3

In GTAW (TIG welding), what does 'AC' current provide when welding aluminum?

Accepted Answer

Cleaning action that breaks up the aluminum oxide layer on the DCEP half-cycle

Answer

The DCEP half-cycle of AC current provides a cathodic cleaning action that blasts away the tenacious aluminum oxide layer, enabling fusion.

Question 4

What is the primary advantage of FCAW (Flux-Cored Arc Welding) over solid wire GMAW?

Accepted Answer

Higher deposition rates and improved performance on rusty or dirty steel

Answer

FCAW provides higher deposition rates than solid wire GMAW and the flux core provides better tolerance for surface contaminants.

Question 5

In SAW (Submerged Arc Welding), the arc is submerged beneath:

Accepted Answer

A layer of granular flux

Answer

In SAW, the arc and weld pool are completely covered by granular flux, which melts to form a protective slag and suppresses arc radiation and spatter.

AWS Practice Test

AWS Practice Test

AWS AWS Welding Processes & Equipment