Grades of Helium

[Mike Edmonston]

Since HE analyzers are really just high tech temp gauges you don't really know the contents. I.e. if the contaminants behave similarly to He, they will measure as He.

You'd need to know how the contaminant behaves thermally before knowing if the sensor was accurate.

Percent quantities of say nitrous oxide would be very very bad at depth.

HiJack (pun intended)

You bring up a valid point. How do I know what is truly in the Helium that I buy? Every supplier has different names for different grades, and they aren't even sure what's for diving and what the grades mean. I am not a chemist and don't have access to a Spectrum analyzer ( I watch C.S.I. ) So how do I tell. I want the Nitrous for my car, not for my bottom time!

I deal with Praxair, and have been very happy with them, but their "Technical diving helium" grade gas is $172 per K tank

I would love to pay $60 or $70 per bottle, but I need to know which praxair product corresponds to what you guys are using.

Cheers

Mike

 

[Teamcasa]

I am not a mixer or a tech diver.
However, I do weld. The price range for gas is volatile. I have seen acetylene, O2, helium and argon vary as much as 100%.
My current vendor, AirGas treats me very well – now. Local managers have a wide latitude in the sale price.

Dave

 

[loosebits]

As far as I know, the only gases that are usually placed into cylinders with CGA-580 valves are nitrogen, helium, argon and CO2. I'd have to do the math but I'm guessing that if they emptied the cylinder before filling (e.g. drained it down to 14.7 psi) the only gas in that list that could possibly cause problems at sub-1% levels is CO2.

 

[rjack321]

As far as I know, the only gases that are usually placed into cylinders with CGA-580 valves are nitrogen, helium, argon and CO2. I'd have to do the math but I'm guessing that if they emptied the cylinder before filling (e.g. drained it down to 14.7 psi) the only gas in that list that could possibly cause problems at sub-1% levels is CO2.

Acetylene, nitrous oxide, methane and more can all be introduced during filling, during use if not vacuumed before refilling, or from the cryogenic seperation process itself.

 

[rjack321]

HiJack (pun intended)

You bring up a valid point. How do I know what is truly in the Helium that I buy? Every supplier has different names for different grades, and they aren't even sure what's for diving and what the grades mean. I am not a chemist and don't have access to a Spectrum analyzer ( I watch C.S.I. ) So how do I tell. I want the Nitrous for my car, not for my bottom time!

I deal with Praxair, and have been very happy with them, but their "Technical diving helium" grade gas is $172 per K tank

I would love to pay $60 or $70 per bottle, but I need to know which praxair product corresponds to what you guys are using.

Cheers

Mike

The counter guys at my dealer don't know any of this stuff, I had to call the lab quality assurance guy. I pretended I had mysterious industrial process and needed to know the potential contaminants in the different grades. For He you want USP grade OR 4 nines with gaseous hydrocarbons <0.5 ppm Test at at least the batch level (not necessarily every tank like UHP IMO)

 

[Rick Inman]

Maybe for not much longer. Friend of mine was paying that,and last time he bought gas it went to $135

Well, I was told to look for about an eight dollar increase. But I get a special price because the manager is a friend. :monkeydan

 

[Mike Edmonston]

Ok guys, here's what I got so far.
I went to PRAXAIR yesterday and here's what they offered:

1. Helium compressed - HE 5.0UH-T - 291CF - $100 (T bottle 5.0 UHP grade super pure)
2. Helium compressed - HE M-K 217cf - $121.28 (K bottle / USP Medical grade)
3. Helium compressed - HE K 217cf - $84 (K bottle / Balloon grade)
4. Helium compressed - HE 5.0UH-6K - 480cf - $225 (K bottle 6000psi 5.0 UHP grade super pure)

From a price standpoint, it looks like #1 is the way to go. Almost 300cf of gas for $100.

Which ones do you guys use? the 6000 psi bottle has 480cf of gas, but I can't find a 2 stage reg that goes to 6000 psi! Any suggestions?

thanks everyone.

Cheers.

Mike

 

[Jimmer]

Mike: http://www.hypresequip.com/listparts.asp?category=2 if you scroll down, they offer 6000 PSI regulators with or without gauges, is this what you're talking about?

 

[rjack321]

Are you partial pressure or CBing?

for PP, the cost of the 6000psi reg will probably be worthwhile. for CBing it doesn't matter too much since you can suck the supply down to nothin'

 

[Mike Edmonston]

Mike: http://www.hypresequip.com/listparts.asp?category=2 if you scroll down, they offer 6000 PSI regulators with or without gauges, is this what you're talking about?

Not the same regs, I was referring to the actual regulator that mounts to the HE bottle.

Thanks

Mike