Has anyone tried it for TIG welding? Is it pure enough for welding? It's only advertised as being used for filling balloons etc. I'd quite like to have a small bottle on hand for aluminium TIG, just to mix in with Argon, but a rental cylinder isn't practical cost-wise.
Thought that would be the answer I suppose I could get a small cylinder from Dixons of Helimix, but it'll be £60/year for something that barely gets used, and won't want to return it "just in case". I also don't feel the need for a bigger TIG set yet either, since all paying work so far has generally been steel/stainless, and when i upgrade I'll want a top end 300 amp class machine, which I can't justify atm.
A mix of what? I have got a balloon helium somewhere, I will have a look at it but I just presumed it would be pure helium? (Well, maybe 95% or something, not sure how pure they would bother getting it?)
It's quite an expensive gas to produce, generally distilled from natural gas according to wiki. I wonder if balloon gas is generally stocked from out-of-spec production, or if it's "cut" with air from pure sources?
I thought the helium shortage ended a few years ago? I have not had any problems getting it in the last 5 years or so. According to some balloon instructions a minimum of 92% helium is required to float one. BOC show balloon gas as a minimum of 95%. Hobbyweld say 100% (I'm not sure I believe that) but they do call it helium rather than just balloon gas. Thinking about it, the bottle I have is probably helium as I have to connect a regulator with a fill adaptor onto it . Most of the balloon gas I see at parties has a permently attached valve although that's normally small thin bottles
Until recently it was thought there was an finite amount. Vast amounts was required for cooling in magnetic resonance cat scan and mri machines. Since then they found some in a cupboard, so alls well
I think the stuff that leaks out when they are purging/filling the MRI machines is often sucked off the roof and sold as balloon gas.
I would bet that the cheapest part of an MRI machine would be the gas! For a £2m machine, a couple cubic metres of high spec helium isn't really the bulk of the cost... Although I guess modern regulations would make you recapture any planned gas release. A lot of those articles abouut running out of helium were written around 10 years ago or even further back... when there was a lot of demand for helium but commercially viable refinement was scarce. Welding, Superconductor research, chromatography, etc, lots of uses for helium springing up and demand going up over the last half century. Back then, LNG wasn't such a big deal, but nowadays, it is a big industry in itself... and with availability of LNG comes commercially viable ways to extract helium from it. EDIT: Still looks like a global shortage will occur in the next 50 years, though
I dont think pure Helium is any good for welding....too hot I think I honestly cant remember so dont take my word for it.......google it
I’ve seen pure helium used for very specific welding processes. Usually the TIG machine will start the arc on argon and then switch to helium ones the arc is initiated. Straight helium isn’t an ideal shielding gas for AC TIG welding, the ionisation energy is higher, and therefore you get less cleaning action. It’s also Very light unlike argon, so you’d need more gas to get the same coverage. 50/50 is plenty for most applications. DC TIG of aluminium is carried out with pure helium. Helium also a useful gas when welding refractory metals or copper.
Isn't that how it all started, heli-arc welding? Presume they have changed over the years for a good reason...
100% right Brad. I’ve seen a few people using pure helium for D.C. TIG welding aluminium but it is a very specialised process. Absolutely no advantages to using pure helium for the vast majority of applications
