Principles of Welding

What does a SHIEDING GAS do?

• Magnetic interference causing arc to wander

• Gas that chemically reacts with the weld pool

• Gas, vapor, or slag protecting the arc and molten pool

• Movement of the electrode side-to-side

What is INERT SHIELDING GAS?

• A gas that reacts chemically with the weld pool

• A gas that does not chemically react with weld pool (e.g., argon, helium)

• Created by electrode flux combustion

• Used only in AC welding

Self-Shielding Systems

• Uses bottled gas such as argon or helium

• Electrode coating burns to produce protective gas

• Produces a hot puddle by adding oxygen

• AC welding for aluminum

Reactive Shielding Gas

• Gas that chemically combines with weld pool (e.g., CO₂, oxygen)

• Gas that does not react chemically with the weld pool

• Gas made only from flux

• Magnetic disturbance during DC welding

Alternating Current (AC)

• Flows in one constant direction

• Changes polarity in a sine wave pattern

• Uses only DCEN polarity

• Is used only for steel welding

Direct Current (DC)

• Changes polarity every 1/60th of a second

• Flows in a single constant direction

• Used only in GTAW welding

• Produces low penetration

Arc Blow

• Magnetic field effect in DC welding causing arc deflection

• Large burst of shielding gas

• Side-to-side motion to fill wide gaps

• A type of electrode

how do you get rid of arc blow

• turn machine on and off

• switch to AC setting

• IDK i just work here

• Yes

Arc Length

• The speed of the welding torch

• Distance between electrode tip and base metal

• Length of the weld bead

• Width of the weld puddle