Page 201 - CITS - Welder - Trade Theory

WELDER - CITS

• Small HAZ width

• Low power consumption
• better penetration
• better control when welding out of position
• easy to use on thin materials
In this type of power source, the supply current is not constant and it is being fluctuated from low level to high
level. This causes low heat input to the metal and hence distortion effect will be less. (Fig 1,2)

Fig 1 Fig 2

AC - Alternating Current - Square Wave (Fig 3)

Fig 3

With the advent of modern electricity AC welding machines can now be produced with a wave form called Square
Wave. The square wave has the benefit of a lot more control and each side of the wave can be, in some cases,
controlled to give a more cleaning half of the welding cycle, or more penetration.
Once the welding current gets above a certain amperage (often depends on the machine) the HF can be turned
off, allowing the welding to be carried on with the HF interfering with anything in the surrounding area.
Extended Balance Control
AC balance control allows the operator to adjust the balance between the penetration (EN) and cleaning action
The down side is - more set-up cost and more operator training.

Pulsed TIG consists of
Peak current - This is set up higher than for non-pulsed TIG.

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CITS : C G & M - Welder - Lesson 61-76 CITS : C G & M - Welder - Lesson 61-76