AWS Welding Processes 3

Question 1

What is the main difference between FCAW-G and FCAW-S?

Accepted Answer

FCAW-G requires external shielding gas while FCAW-S is self-shielded by the core flux

Answer

FCAW-G (gas-shielded) requires an external shielding gas supply, while FCAW-S (self-shielded) generates its own shielding from the flux core, making it usable without gas cylinders.

Question 2

In SMAW, what does the coating on a covered electrode primarily provide?

Accepted Answer

Shielding gas and slag to protect the molten weld metal from atmospheric contamination

Answer

The electrode coating burns during welding to generate shielding gases and form a slag layer that protects the molten weld pool from oxygen and nitrogen in the atmosphere.

Question 3

Which electrode classification is a low-hydrogen SMAW electrode suitable for welding high-strength steels?

Accepted Answer

E7018

Answer

E7018 is a low-hydrogen iron powder electrode with a 70,000 psi minimum tensile strength, widely used for structural and high-strength steel applications.

Question 4

What polarity is typically used for GTAW on aluminum and why?

Accepted Answer

AC, because it provides a cleaning action on positive half-cycles and penetration on negative half-cycles

Answer

AC is used for GTAW on aluminum because the electrode-positive half-cycle provides a cathodic cleaning action that breaks up the refractory aluminum oxide, while the electrode-negative half-cycle provides penetration.

Question 5

Electroslag welding (ESW) is most appropriate for which application?

Accepted Answer

Joining very thick plates (over 1 inch) in the vertical position in a single pass

Answer

ESW is designed for welding very thick plates vertically in a single pass using a molten slag bath and water-cooled copper shoes to contain the weld pool.

AWS Practice Test

AWS Practice Test

AWS Welding Processes 3