By -
Date 10-11-2005 13:03
I can't help with your question regarding prequalified procedures for EGW. However, I did witness some of Samsung's attempts to use this process for the same application that you speak of (i.e. vertical hull splices between blocks in drydock).
They had numerous problems with this. The main problem is that a water-cooled copper cooling shoe is used on the inside and must run up the splice in tandem with the welding head. This necessitates cut backs on the hull stringers to allow the cooling shoe to pass through. Equipment setup was lengthy, especially on the inside. Fitup was also critical, and of course at the block splice stage there tends to be many fitup variations in gap, ranging from metal bound to large gaps (obviously the goal is to maintain overall dimensional requirements).
At the end of the day, Samsung found it to be faster to use semi-auto FCAW to weld up the inside, followed by backgouging and the use of mechanized FCAW on the outside. And of course this process was not suitable for some base materials, due to the truly massive heat input.
Mankenberg
