Nitrox Blending Rental of Air Cyclinders

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I guess hard heads are difficult to counter. Lampton Welding is the largest supplier of welding supplies in this area. Sells to hospitals, fills medical oxygen cylinders for many suppliers, supplies aircraft plants, etc. They only purchase medical grade Oxygen and purchase from one of a very few extractors in the US which supplies LOX to most all large pumping stations. The Primary difference is for medical Oxygen they evacuate system/cylinders and certify the contents. Medical and welding grade tanks are never filled on the same trunk system -- but the oxygen supply (LOX) is medical grade. Airgas process is just the same.
Jim Shelden

Thanks for the reply,

It does make sense. If you are a NADCAP, ISO or some other Quality control org certified supplier, you may be either required to segregate material supply or test everything that goes out. I don't know the exact requirements but only guessing. Segregating as you describe may be the cheaper solution. I'm thinking that many more cylinders of "industrial" go out the door than "medical". Then just test the batches you need ("medical" only) and don't leave into question if non-tested batches have somehow contaminated the rest of your supply or any of your delivery lines.
I suppose some other people's options will vary.
 
Yes, The process is different for medical supplies. Medical oxygen only is filled on one set of fill stations - evacuated and all other requirements. Welding gas and others are never filled on this line. Welding oxygen and other gasses are filled on other lines - specifically for the gas requirements.
Jim Shelden
 
I was unable to get O2 in my area without a doctor's prescription. Luckily I just wrote an Rx for myself.
 
Must be nice to have connections like that. The things I could do if I had an RX Pad.
 
If you want to blend nitrox there is this cool course called "Nitrox Gas Blender" taught by many different agencies. Or you know, you could just start trying some random **** and see what happens.
 
I buy medical grade in OZ. Don't need a prescription in OZ. its cheaper from my supplier than welding grade (although it wasn't until I suggested I go else where). Its about $80 AUD a G size cylinder although the rental is a killer at about $28/month. I have been partial pressure but bit the bullet and got a pump finally so can suck most of the gas from a G and still blend an 80 mix with low supply pressure.

Helium on the other hand they want around $1400 a G cylinder which is ridiculous. I can buy and store a G at a LDS for about $450, so still working on a fix for this.
 
Folks use avaiation grade cause they can not get a script for med O2. Its all the same O2 If you were talking about filling a tank form a welding tank that is currently being used for welding, there is a risk of some back filling of acetalin into the tank. Once purged you will never have that problem again. I would not recommend using an active welding O2 tank to PP blend. My understanding is that specs for the O2's are welding 99.4% pure. med is filled after the bottle is evacuated and only has to be 85%. Avaiaton is dried O2. when it all comes form that same bulk tank it is all the same all 99.5 or better 99.9999 if form LOX so it is the handling that varies for the med stuff and the avaiation and industrial is the same stuff. they just charge differently for the use and related liability. My O2 tanks have never been connected to a Ox/act hose. so no contaminates at all. I fill them form a concentrator at home. It is slow but its free. I have 1000 cu ft of 96% O2. Yes the rest is argon but it has little effect on the final mix. By that I mean PP blending using 12% pure having 4% of the 12% as argon. It does not add much to the argon content in the fnal mix. May be 1.5% argon in final mix instead of 1% on an EAN32 tank.
 
Living in Missouri - my Praxair dealer supplies "Technical Diver Grade" Helium and Oxygen. A T cylinder of HE costs about $180. A T cylinder of oxygen is about $39. A T of Argon is about $200.

They only lease / rent tanks. No option to purchase. Don't believe they will fill user owned tanks.
 
Living in Missouri - my Praxair dealer supplies "Technical Diver Grade" Helium and Oxygen. A T cylinder of HE costs about $180. A T cylinder of oxygen is about $39. A T of Argon is about $200.

They only lease / rent tanks. No option to purchase. Don't believe they will fill user owned tanks.

What volume is a T cylinder. In OZ a G is 50 litre x 200 BAR so 10,000 litres so about 350 cu ft of gas. I can buy an empty G cylinder for $700 but cant pump it across due to the volumes. I could partial pressure it but still end up with only half. I can buy a G full but the price goes up from $80 rented to $180 owned for the gas.
 
What volume is a T cylinder. In OZ a G is 50 litre x 200 BAR so 10,000 litres so about 350 cu ft of gas. I can buy an empty G cylinder for $700 but cant pump it across due to the volumes. I could partial pressure it but still end up with only half. I can buy a G full but the price goes up from $80 rented to $180 owned for the gas.

The Helium T Cylinder from Praxair is 291 Cu Ft. at a working pressure of 2640psi.- 99.995% purity
The Oxygen T Cylinder from Praxair is 337 Cu Ft. at a working pressure of 2400psi - 99.5% purity
 

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