Hello all from Virginia

Thanks guys for letting me join the forum..... I'm a welder but never touch anything like a torch, welding rod, wire brush or chipping hammer (only at home in the garage). I operate an Electron Beam Welder for a National Laboratory here in Virginia and weld Niobium probably 90% of the time. We weld other metals but nothing ferrous due to cleanliness. These parts are machined for precision fit and fused together with a stream of electrons inside of a vacuum chamber (68"x68"x84") at 7x10-5 Torr. The claim to fame for Niobium ('Nb' on the periodic table) is that it is a superconductor at -456°F (liquid helium) and we construct superconducting cavities for a particle accelerator. I write the programs for this CNC (welder in a box) machine to do the welds in a pristine environment in the vacuum chamber.

Anyhow, we bought the 255EXT and it's a marvel. The last welder that we owned was a Lincoln 300-300. (sort-of puts me in an era) This machine has settings I've never seen before...

Hope to learn some new techniques here on the forum....so will have questions.

Thanks
Bill C

The electron gun is upper left. The hot thing is a half of a single cell 1492MHz superconducting cavity. This operation was an experiment in remelting the cavity inner surface with the electron beam circular raster and under focused. This is Niobium - melting temperature is 4474° F.
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Originally Posted by BillC

The electron gun is upper left. The hot thing is a half of a single cell 1492MHz superconducting cavity. This operation was an experiment in remelting the cavity inner surface with the electron beam circular raster and under focused. This is Niobium - melting temperature is 4474° F.
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Very interesting. To get an idea of scale, what size is the 3 jaw chuck on that positioner?

Welcome aboard number two Bill.

I know you got on now, I can see a post. Must have been the forum fixing that messed things up. The EXT units are great, sometimes to many settings.

So now I have to go google Niobium. hahaha.. Can we ask the customers name for this cool stuff? Just kidding, do not want you to have to kill me.

1.5 Ghz, wow. What kind of power to drive it?

https://en.wikipedia.org/wiki/Niobium

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Originally Posted by Rambozo

Very interesting. To get an idea of scale, what size is the 3 jaw chuck on that positioner?

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The chuck you see is one of five on a gear driven 'multi chuck' set-up for doing multiple welds on one chamber pump down. They are 5" chucks. The cavity in the photo is Ø8.1" on the equator (large diameter). The cells are deep drawn from discs cut from 1/8" sheet then machined and welded either to a beam tube (as in the photo) or to the iris of another half cell to begin the fabrication of a multi-cell cavity - they then become quite complex depending on the design and purpose.

The lab is quite a place...We are one of very few in the world that has the capability to fabricate these superconducting cavities. I'm doing welds for many other labs including welds for components of the Relativistic Heavy Ion Collider at CERN in France. I will send a link to Jefferson Lab.

Bill

https://www.jlab.org/sites/default/files/fulltour.html

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Originally Posted by everlastsupport

Welcome aboard number two Bill.

I know you got on now, I can see a post. Must have been the forum fixing that messed things up. The EXT units are great, sometimes to many settings.

So now I have to go google Niobium. hahaha.. Can we ask the customers name for this cool stuff? Just kidding, do not want you to have to kill me.

1.5 Ghz, wow. What kind of power to drive it?

https://en.wikipedia.org/wiki/Niobium

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Mike, The accelerator at the lab runs at 12 GeV or 12 giga volts - the result of a recent upgrade at the lab. Basically the lab is the most powerful electron microscope in the world. The virtual tour explains some of this (a lot of it is still a mystery to me...). SRF where I work is R&D - the D for me is usually DUH!
Bill

Sounds like some really neat machines. The D will come around in no time I am sure. lol