CSWIP Notes – GTAW / TIG welding process
The questions and answers based on the document no. WIS5-90516b - CSWIP 3.1 Welding Inspector. These question are separated by each section, it makes easy for reading and learning.
Q_12.1: Which polarity is normally used for GTAW welding of aluminium?
Most materials welded by GTAW require DC EN, but aluminium is very difficult to weld. Aluminium is often welded using alternating current (AC). I am not experience in aluminium welding process, please learn more TWI Job Knowledge 6 or welding consumable data sheet / its certificates.
Q_12.2: When considering the tungsten arc welding process what is the purpose of the down-slope (slope-out) control?
Answer: To help prevent the formation of crater pipe and possible cracking.
Note: It is normally find in at the end of weld pass, after switch off arc. You can see clearly on PT method for stainless steel.