Cu/Ni and mild steel

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I don't think I'm actually going to make this weld, but lets say I needed to pass a 90/10 Cu/Ni pipe (small, around 1") through a bulkhead.  Would it be possible to weld the pipe to the mild steel to seal off the penetration?  What would you use?  Some sort of inconel rod?  Are there any stick weld options?
Reply:Not with economy and electrode both, can you give more info? Honestly this is getting out there if your a weldor.Matt
Reply:How thick is the bulkhead material? I have some old Arcos 3N10 in 3/32" which would probably do that well, if the steel isn't too thin. I've forgotten it's current designation but here's a list of some current alloys from Arcos:http://www.arcos.us/nickel.asp
Reply:Bulkhead is 5/16ths, the pipe would either be 1" or 1 1/4" sch40.  We're installing a saltwater flushing system for the heads on a work boat.  Basically, I'm trying to sell them on the Cu/Ni idea.  The company keeps using sch80 steel pipe and worse, they may install sch80 galvanized pipe on this boat.  They tell me, it will be years before the pipe rusts through.  Yes, this is true with the steel pipe.  The galvanized is more prone to pitting and will perforate faster.  The trouble is, while it may take years for heavy pipe to corrode through in this application, it doesn't take nearly as many years to corrode shut.  I am sick and tired of having to rip boats apart to remove plugged sections of pipe.  I know that Cu/Ni would be the most ideal pipe for this situation and the pipe itself isn't really that expensive per foot.  It's the fittings that add up.  So, instead of trying to stack up some assortment of fittings where the pipe passes through a bulkhead it would be easier just to weld around the pipe to seal the bulkhead penetrations.
Reply:Checked your link, they list AWS ENiCu-7 for joining Cu/Ni alloys to steel.  I may even have some of these lying around.
Reply:silver braze ?
Reply:I agree with Weldbead, silver solder with safety-silv 50N and stay-silv white flux would be the best bet
Reply:Alright, does anybody have experience joining Cu/Ni pipe fittings.  I've seen them brazed in the past.  This holds up well to saltwater?  As for the 50N, I always keep an oz of this around because it is so handy to have but my company complains about the cost.