CWI Welding Process Principles 2

Question 1

In SMAW, what is the primary purpose of the flux coating on the electrode?

Accepted Answer

Provide shielding gas and slag protection

Answer

The flux coating decomposes during welding to produce shielding gases and form a slag layer that protects the molten weld pool from atmospheric contamination.

Question 2

Which welding process uses a non-consumable tungsten electrode?

Accepted Answer

GTAW

Answer

Gas Tungsten Arc Welding (GTAW/TIG) uses a non-consumable tungsten electrode, with filler metal added separately if needed.

Question 3

What does the term 'polarity' refer to in arc welding?

Accepted Answer

The direction of current flow in the welding circuit

Answer

Polarity describes whether current flows from electrode to workpiece (DCEP) or from workpiece to electrode (DCEN), which affects heat distribution.

Question 4

In GMAW short-circuit transfer, metal transfer occurs when:

Accepted Answer

The wire tip contacts the weld pool and the arc extinguishes momentarily

Answer

In short-circuit transfer, the wire periodically touches the weld pool, causing a short circuit that extinguishes the arc until electromagnetic pinch forces separate the droplet.

Question 5

Which of the following best describes the 'keyhole' technique used in plasma arc welding?

Accepted Answer

A small hole formed through the full thickness of the joint by the plasma arc

Answer

In keyhole PAW, the concentrated plasma jet penetrates completely through the base metal, forming a small hole that is filled as the arc travels along the joint.

CWI Practice Test

CWI Practice Test

CWI Welding Process Principles 2