Welding Process Principles Flashcards

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

Answer: Provide shielding gas and slag protection

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

Which welding process uses a non-consumable tungsten electrode?

Answer: GTAW

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

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

Answer: The direction of current flow in the welding circuit

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

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

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

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.

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

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

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.

What is the main advantage of using DCEP (direct current electrode positive) in SMAW?

Answer: Reduced spatter and deeper penetration

DCEP concentrates approximately two-thirds of the arc heat at the electrode/weld pool side, producing deeper penetration and a stable arc suitable for most SMAW applications.

In submerged arc welding (SAW), the arc is shielded by:

Answer: A layer of granular flux that covers the arc

In SAW, a blanket of granular flux completely submerges the arc, providing shielding and producing a slag layer that refines the weld metal.