Looking for a replacement for bronze sil-brazed unions

[JoeBobJenkins]

I'm working on a project where what was used before for 3000lb and 1500lb valve end was a navy drawing for silbrazed unions (DWG 1385943 and 1385946). We're looking to go away from sil-brazing and I was hoping to see if there were another option in terms of a spec I can call out. I was looking at ASME B16.11 but that doesn't really cover what I'm hoping to find (unless I'm reading it wrong). I'm relatively new to this and I've learned they no longer like to use sil-brazing. But I need some sort of standard to make the customer happy.

 

[MintJulep]

Sorry, but the problem that you're trying to solve really isn't clear.

When I ask my wife what she wants for dinner and the answer is "not Italian" I still don't know what she wants to eat.

In general, fittings can be attached to pipes or tubes by:

1. Threads
2. Welding
3. Brazing/soldering
4. Compression

Seems like "they" don't like option 3.

What is "their" opinion about 1, 2 and 4?

 

[EdStainless]

Or option #3 with a different filler?

 

[TugboatEng]

Sil-Braze is used for class 200 piping systems using 90/10 copper nickel pipe. For the class 1500 and 3000 systems I see 70/30 copper nickel. Connections are welded with ERNiCU-7 if I am remembering correctly. The ERNiCu-7 filler can be used for butt weld fittings in 90/10 as well.

A few reasons there may be an aversion to sil-braze is the cadmium content, fluorides in the flux, or the general aversion to the use of acetylene in shipyards. Most Sil-Braze alloys have cadmium free alternatives.