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jcopado2
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I have a test coming up in a few days and it's welding on 2" copper nickel pipe. Now I've welded stainless, carbon, and aluminum but I've never even touched nor seem copper nickel welded. I've been watching videos all day over it and it just seems like you put more tacks than you usually would and to me it looks like they have welded their root, hot, and cap pass all in one pass. Copper nickel seems more of a lot of feeding your rod a lot more. Also the gap seemed a lot tighter than usual. Any tips or anything would be greatly appreciated
hacadacalopolis
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I have watched several guys at my shop weld monel 400 with a preheat of around 200F or more. We are advised at my job to generally keep nickel alloys with a preheat. Im not sure if copper nickel necessarily needs it. Could be more of an issue with dissamilar joining.

The puddle can be a little sluggish like iconel- but i dont believe it is as hard. When welding the root just remember not to develop a concave beed. I dont know what position you are going at this test. But i have tried 6g at a school one time like you are preparing for i think. The 2" coupon, It was very hard. It was really just hard to tie in, because i would get the puddle too hot adn dirty on bottom.


The welder that put together two large sections monel 400 kept it very clean and did add a good bit of wire. sometimes the puddle would try to slightly jump on either side of the bevel. For the most it was fused and even. And depeding on dominant alloying material you may have to move faster with it as it heats up. Such as higher copper content
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jcopado2 wrote:I have a test coming up in a few days and it's welding on 2" copper nickel pipe. Now I've welded stainless, carbon, and aluminum but I've never even touched nor seem copper nickel welded. I've been watching videos all day over it and it just seems like you put more tacks than you usually would and to me it looks like they have welded their root, hot, and cap pass all in one pass. Copper nickel seems more of a lot of feeding your rod a lot more. Also the gap seemed a lot tighter than usual. Any tips or anything would be greatly appreciated
Welcome to the forums jcopado2, take a moment and introduce yourself in the new members forum, thanks.

I've welded a fair amount of Monel 400 but not any pipe, surely you will be provided some coupons to practice with?
Richard
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Copper and Nickel institute offers free guides for welding these alloys. http://www.stainless-steel-world.net/pdf/12014.pdf

Main things shortly:
- Keep everything clean
- Avoid weaving, because alloy is sluggish and generates porosity.
- Keep your heat input low
- And for last but not least! Select the right filler!!! Wrong filler will produce porosity and your welds are rejected.


Perhaps you have already checked these videos from youtube. It's a series of videos by Nickel Institute.

t2JZYn819DQ




Good luck to your tests :!:
-Markus-
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