Scavenging helium

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@iain/hsm when is the new one due to be released?

When I've finished doing a 10 year continuous duty long endurance running trial and at that point I may just be happy enough. But so far only 89,549.9 hours up to 21st April when the last photo was taken so no cigars yet.

And for those of you still counting I know what 89 thousand hours is. But just another thousand and we reach the 90K the crankshaft design life and another twenty thousand hours on top of that and we are into Mil-Spec or vintage car mileage one of the other.

IMG_4259.jpg
 
@iain/hsm they discontinued the direct drive microboost though and haven't heard when the new version is due to be released

They may have............ I couldn't possibly comment. lol

But we Brits dont care over here on what you lot do or vote for, But too many European customers dont listen too well to us lot or you lot in the land of the free so 3rd leg live wire electricals and dropping the SA-6 range an't going down too good with them. Vorsprung durch Technik, I guess dont change what ain't broke.
 
BTW the hour meter is showing considerably more than 10 years.

Michael

Michael. You need to consider wearing glasses. Its 10 years I should know. 89549 point .9 hours
At least now you know why I said:
"And for those of you still counting I know what 89 thousand hours is."
At least you know it runs OK
 
Iain, are you ever going to make and sell them, preferably before your 70th birthday, or is this just an exercise to make us jealous?:daydream:
I would like to buy one if it can pump to 300Bar, but if its hopeless getting one from you, I can always pay a fortune to Masterline and use 12L tanks for the intermediate pressures.

Michael
 
Iain, are you ever going to make and sell them, preferably before your 70th birthday, or is this just an exercise to make us jealous?:daydream:
I would like to buy one if it can pump to 300Bar, but if its hopeless getting one from you, I can always pay a fortune to Masterline and use 12L tanks for the intermediate pressures.

Michael

Hi Michael

I think we are at cross purposes here with the OP subject of the post being gas scavenging ie draining the dregs out of a cylinder or bank and in the case of my sugestion incorporating three (3) stags of compression to both regain a reasonable P2 pressure from a tiny insignificant inlet P1 pressure and in addition reduce adiabatic compression ratio's heat, gas velocity etc especially with the oxidising gases such as oxygen.

On the other hand your requirement for a 300 bar P2 pressure would negate this little scavenging pump to have in the order of 5 to 6 stages of compression to complete a 300 bar discharge pressure with the same level of safety, compression ratio heat dissipation etc.

By contrast the Masterline you suggest being a single stage double acting electrical booster pump is better suited for your 300 bar discharge pressure requirement but using inert gases such as air or helium and would require in the order of 180 bar inlet pressure to complete the task or risk a much higher compression ratio.

Its a real consideration that the Masterine booster was never originally designed for oxygen or helium but dry breathing air and being single stage double acting lacks the additional cooling bonus an air driven booster pump such as the Haskel offers when compressing the oxidizing gases.

(I am also well aware of re plumbing the pipework on the Masterline to make it appear a two stage not withstanding still using the two identical piston diameters and stroke.)

Apples and oranges or some such fruit no doubt but a gas scavenging pump and a booster pump are two very different animals. It is a great pity that our industry, the instructors and trainers cannot and do not afford its students and members the benefit of understanding these fundamental differences and considerations.

As for your timeline of before I reach my 70th birthday what is it that's said.
"For what is your life? It is even a vapour, that appeareth for a little time, and then vanisheth away".
Teach us to number our days. Iain
 
https://www.shearwater.com/products/peregrine/

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