Page 187 - CITS - Welder - Trade Theory

WELDER - CITS

On the half cycle, where the tungsten is positive electron welding current will flow from base material to the
tungsten. This will result in the lifting of any oxide skin on the base material. This side of the wave form is called
the cleaning half. As the wave moves to the point where the tungsten becomes negative the electrons (welding
current) will flow from the welding tungsten to the base material. This side of the cycle is called the penetration
half of the AC wave form.

Current type DCSP
Electrode Polarity Alternating

Oxide Cleaning Action Yes (once every half cycle)

Heat Balance in the Arc 50% at work end 50% at electrode end

Penetration Profile Medium

Electrode Capacity Good

GTAW Torches, Types, parts and function
Objectives: At the end of this lesson you shall be able to
• describe the GTAW torch
• explain the GTAW types
• explain the GTAW parts and function.

WELDING TORCH

GTAW torch, disassembled
GTAW torch with various electrodes, cups,
collets and gas diffusers

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CITS : C G & M - Welder - Lesson 49 - 60