HI Glenn,

I agree that "slope-out" would be more understandable to most folks even though I understood what you meant when you used the term "Fade-out" in that one would gradually slope down, or fade down the current to zero slowly enough to reduce the size of the crater to a dot either by programming it into the power source usually for automated applications although it is also used in applications where a foot control, or torch mounted amp control is not available (I've used many a GTAW torch where we had to use slope controls via the power source, and so have many other boilermaker welders as well because the contractor we worked for were too cheap to provide us with torch mounted amp controls. :( ), or to do it manually with the use of either a foot pedal current control or torch mounted current/amperage control as well in order to avoid exactly what you pointed out as crater cracks. ;) For pipe, I have always purged the root of the joint and continued to use a purge after the root pass for at least one other pass over the root pass, but this depended on the wall thickness of the pipe, WPS, etc. ;)

Hi Milton,
I personally have welded a huge amount of various Inconel grades, NiCu, CuNi pipe in Submarines and power plants as well as Inconel cladding in Crackers, Cokers, a wide variety of heat exchangers and pulp paper mills also. ;) If you have to weld it using SMAW it really is a "PITA" when it comes to the slag sometimes especially out of position, but like Glenn said earlier, it really is a pleasure once one gets used to the initial sluggishness with GTAW. ;)

Respectfully,
Henry