Electro-slag welding

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Have any you guys (or gals) ever seen electro-slag welding being  done . It IS a quite exotic Process , and pretty **** hot , too-at least what i saw, at Kaiser steels' fabshop about 30 some years ago . If any body is curious , i might try to explain it - Roy Hodges
Reply:I have never seen it or heard of it, but would like to. did a google on it for some pics but not much out there looks kind of like sub arc.
Reply:When I saw it , at Kaiser Steel's Napa,Ca. Fab shop, they used it for welding 2 big ,thick sections together that were "stands" for a 30,000 ton hydraulic press , for forming plate steel into an "O"shape , as part of making pipe . the stands were lying horizontally, about 8' high , about 2" apart (gap) at the bottom , and 2 1/4" gap at the top of the weldment . the steel was 7" thick . each piece was about 8' long  , i think . the bottom was covered with a water cooled shoe, as was about 18" of the gap,also w/water cooled shoes . the welding wire -2 of them were fed down the gap, through hollow electrodes that melt off , into the weld as the puddle comes up . each wire is fed by a 600 amp hobart power source . the electrode was about 7/8" dia. with small hole through it , and a thin flux coating on it . as the weld came up , the shoes were removed from the already welded part and moved up to contain the molten metal . before the weld was started , some granulated flux was poured into the weld area & it floated up on top of the weld. Once the weld was started , it could not be stopped,untill complete . Naturally, this thick stuff had to be preheated , talk about hot! the strip heaters had to stay on ,also, for several hours after welding to allow for SLOW cooling .
Reply:I am not sure why but for some reason it fell out of favour.  I suspect some catastophic failures.  I have read articles in the past few years that predict a comeback now that we have very precise power supplies that can customize welding current.  Like Sub Arc it would be a great process when it works but when things go wrong......
Reply:I see. I never heard of any failures at the Kaiser plant. But, they did N D T on all the welds , either x-ray or ultrasonic tests. And these always had some repairs  necessary , probably due to flaws in the original pieces (because they was so thick) . i think N D T of the whole PIECES was necessary . Just like every(inch of every) piece of steel that is used  in the pressure hull of every nuclear submarine is   ultrasonically tested , before it is used in the constuction of the sub.
Reply:That sounds awsome. i would love to see that. how much radiant heat was comming off of that thing? ill bet it was intense.
Reply:intense ?  more than THAT !  it was preheated to 500 F. imagine the heat around it. sweat poured out of the welders' leathers