Welding with Inert Gas.

[RmyWelder85]

Has anybody on here ever heard of anybody using inert gases other than helium and Argon? If so; what are the characteristics of the weld produced? Are they pretty much the same as helium and argon?

[Type]

I use C25 which has argon and carbon dioxide. I have never seen this but I think I've heard of someone using 1% hydrogen I beleive. I may be mistaken though.

[H80N]

Has anybody on here ever heard of anybody using inert gases other than helium and Argon? If so; what are the characteristics of the weld produced? Are they pretty much the same as helium and argon?

There is a tremendous variety of gas mix combinations used for welding...

this Praxair Gas Selection manual will explain which gas combinations and their purpose...

http://www.prest-o-sales.com/other_links/gases/PDF/ShieldingGases/Manuals/Shielding%20Gas%20Selection%20Manual.pdf

It also explains some of the physics of the reasons for their choice...

[Ltbadd]

I use C25 which has argon and carbon dioxide. I have never seen this but I think I've heard of someone using 1% hydrogen I beleive. I may be mistaken though.

We use Argon with 2% hydrogen every day TIG welding stainless

[Type]

That's where I heard they use it, with TIG welders. Thanks for confirming what I thought.

[M J Mauer]

Rmy welcome to the forum.

[Electric4Life]

Helium works too

[Bodybagger]

Don't forget about 100% hydrogen. Atomic hydrogen arc welding was used extensively in aviation during WWII.

[Bodybagger]

Check out this film from 1940 by General Electric...

https://www.youtube.com/watch?v=uZwYMyHlWXk

[Synchroman]

Nitrogen can be used as backing gas but won't work as a primary shielding gas. It's not completely inert in an arc setting as it can conduct electricity. It's a very poor conductor but still will conduct, nonetheless. It will also oxidize at high temperature possibly generating NOX, nitrous oxide which is not good for you.

When I was first working at the Rocketdyne company assembling rocket engines, the people in the weld department were using straight helium with transformer machines on DC. This was the original Heliarc process. The welds were the most beautiful that I've ever seen and they were all X-rayed during inspection. That's where I got interested in welding.

[Bodybagger]

When I was first working at the Rocketdyne company assembling rocket engines, the people in the weld department were using straight helium with transformer machines on DC. This was the original Heliarc process. The welds were the most beautiful that I've ever seen and they were all X-rayed during inspection. That's where I got interested in welding.

There's a Rocketdyne F-1 engine on display at the Smithsonian Air and Space Museum. I probably took a dozen photos of the TIG welded hems on the inside edge of the nozzle. I had a friend with me last time I went - he was a Russian exchange student my family hosted when I was in high school and (of all things) now he's a welding engineer back in Russia in the petrochemical industry. He also admired those welds. He said something to the effect of "These welds are made by best of the most perfect welders with tungsten and very pure gas. Anything that go to space or in nuclear plant have best welds of this kind."

[walker]

BTW, hydrogen and CO2 are not inert gases.

[Bodybagger]

I might have misunderstood the OP. I thought by "inert" he meant gases that that shield the weld and do not react with the weld metal.

If he meant "noble gases in Group 18 on the Periodic Table," the answer is no.

You think helium is expensive? Krypton and xenon are about a hundred times as expensive as argon. A bottle might run you as much asone or two Dynasty 200's depending on market price, quantity, etc. And radon is out of the question. So that leaves neon. It's been used in novel processes which is another way to say TIG welding with neon has been done in a laboratory setting at great cost, but it's probably not a road you want to go down unless you've got a research grant to burn.

[Synchroman]

There's a Rocketdyne F-1 engine on display at the Smithsonian Air and Space Museum. I probably took a dozen photos of the TIG welded hems on the inside edge of the nozzle. I had a friend with me last time I went - he was a Russian exchange student my family hosted when I was in high school and (of all things) now he's a welding engineer back in Russia in the petrochemical industry. He also admired those welds. He said something to the effect of "These welds are made by best of the most perfect welders with tungsten and very pure gas. Anything that go to space or in nuclear plant have best welds of this kind."

Yes, I've seen pictures of that F-1. That was after my time at North American Aviation/Rocketdyne. When I worked at the Propulsion Field Laboratory, we were hanging and firing Jupiter and Thor production engines. The stand next to where I worked was where the first Redstone space engine was tested. It was very similar to the V-2.

Apparently, the welders in that era were very skilled. Considering that the equipment they were using would be considered primitive nowadays, the work that they did was really outstanding. The place where the "stacks of dimes" showed up was mainly on the ductings between the turbo pump and the thrust chamber. Some of them were stainless steel and some were aluminum. They had to be perfect since the engines were known to vibrate on cutoff and, in the event of a leak of a fracture, any mixing of the fuel and oxidizer outside of the engine could and did lead to explosions.

I'm sure that welders in aerospace are using the most modern equipment nowadays. That said, I would have to tip my hat to the people who were doing it 50 years ago. It underlines the fact that skill will often trump the equipment used.

[Bodybagger]

Yes, I've seen pictures of that F-1. That was after my time at North American Aviation/Rocketdyne. When I worked at the Propulsion Field Laboratory, we were hanging and firing Jupiter and Thor production engines. The stand next to where I worked was where the first Redstone space engine was tested. It was very similar to the V-2.

Apparently, the welders in that era were very skilled. Considering that the equipment they were using would be considered primitive nowadays, the work that they did was really outstanding. The place where the "stacks of dimes" showed up was mainly on the ductings between the turbo pump and the thrust chamber. Some of them were stainless steel and some were aluminum. They had to be perfect since the engines were known to vibrate on cutoff and, in the event of a leak of a fracture, any mixing of the fuel and oxidizer outside of the engine could and did lead to explosions.

I'm sure that welders in aerospace are using the most modern equipment nowadays. That said, I would have to tip my hat to the people who were doing it 50 years ago. It underlines the fact that skill will often trump the equipment used.

I searched through my forty thousand or so photos and found the ones I took of that F-1 rocket engine...

It's really nice that there are people with such diverse and interesting backgrounds on the forum.

By the way, there must be thousands of feet of welds on each of these engines.