New HP 120's

[arcFlash]

leadking, you're using Ron Benson's tag line again.   

[DetectorGuy]

Thanks for the info people. They are new and it would make sense to keep these as dedicated Nitrox (O2 cleaned) for as long as possible. Especially if they are O2 cleaned from the factory.

The other mini dilema is that while these tanks are 3442 PSI tanks and I would always like to take advantage of a "full fill"... My regs are Aqua Lung Glacias. Yoke style and I don't see the need for din in the near future... the first stage is stamped 3300 PSI on it. I don't really want to limit the pressure of the tanks to the rating on the first stage. Is this a big deal for the extra 142 PSI over the rating exerted on the first stage?

[mattd]

I don't think so.  My yoke regs are stamped 3500 psi and I know they've gone above that a few times.

I look at it this way - if the "normal" range is to 3300, then they must be designed with some kind of safety factor.  4000 might be pushing it, but 3600 or so is probably fine.

[leadking]

He changed his so I'll change mine! 8)

[aknelsonone]

What is the alternative to p/p blending ? 
There are not many membrane systems Who has it?

Andreas

[DetectorGuy]

Mixing the gas in the consumers tank with 100% O2 first and topping it with air to the requested blend would be partial pressure blending. Mixing the gas in the retailers bank of tanks and then transferring this premixed gas to the consumers tank would be banked gas. This membrane system you are talking about must have been before my time.

[rcojr]

The other way of mixing is called Continues Flow brending.
That is when you inject oxygen and or helium into the inlet of a running compressor.
You better know what your doing.
Too much helium and the compressor overheats.
Too much oxygen and the compressor goes BOOM.

The membrane system goes on the inlet of the compressor and removes some of the nitrogen from the incoming air.
Less nitrogen = higher % of oxygen
The only membrane system that I have seen was on the old RLT Diver up at Isle Royale.
Bob 

[deep_al]

youll see membrane systems in remote locations around the world where getting cylinders of O2 shipped in isnt as cost effective as the high cost of membrane systems.  so they are becoming less and less common.

[aknelsonone]

The interesting fact is that the membrane systems are the one you can find not only in the Twin City but also in Roatan. My brother a farmer has several of those membran systems to reduce the oxygen in cold storage for fruits. (slows ripen the fruits) Therefore a lot of technical applications beside producing nitrox for diving.

Back to the subject of partial blending it seems to be out there what the reasons are for the tank cleaning. Now we could attack what the reasons are for the annual VIP?

Is it just a racket to make more money by the dive stores or does anual visual inspection serves a real value added service?

Andreas

[Shooter]

I probably won't have them ready for the 20th but that is going to be so shallow that I can get by on my other tanks. In the long run I think I will label up the 2 hp120 steels and 5 alum 80's. I will keep the other 7 tanks as "air only" for now. So Nate if you happen to know someone in the sign business that can print 7 nitrox stickers for 7 1/4" diameter tanks,I would gladly pay that guy for his artwork.
[/quote]

I will have to downsize my current artwork.  ;D

We can also print custom tank wraps starting @ around $40