Electroslag Welding

Electroslag welding is a process for thick plates in the vertical position. Current flows through a conductive slag bath that generates heat and melts the edges. The bath shields the weld metal and prevents it from running out. You have to set up the plates cleanly with the right gap. If the slag gets too hot, it burns through or the bath runs out, so you control the power via the wire feed speed. It's a very efficient process, but you need experience to keep the bath calm and controlled.